CN1912744B - Method of uniformly coating a substrate - Google Patents

Abstract

A method of and an apparatus for coating a substrate with a polymer solution to produce a film of uniform thickness, includes mounting the substrate inside an enclosed housing and passing a control gas, which may be a solvent vapor-bearing gas into the housing through an inlet. The polymer solution is deposited onto the surface of the substrate in the housing and the substrate is then spun. The control gas and any solvent vapor and particulate contaminants suspended in the control gas are exhausted from the housing through an outlet and the solvent vapor concentration is controlled by controlling the temperature of the housing and the solvent from which the solvent vapor-bearing gas is produced. Instead the concentration can be controlled by mixing gases having different solvent concentrations. The humidity of the gas may also be controlled.

Description

Evenly be coated with the method for substrate

The application is that the name of submitting on May 25th, 2005 is called: the dividing an application of the Chinese patent application 200610082779.1 of " evenly being coated with the method for substrate ", and Chinese patent application 200610082779.1 to be names of submitting on February 21st, 2002 be called: the dividing an application of " evenly being coated with the method for substrate " Chinese patent application 028083024.

Technical field

The application relates to the device that is coated with substrate surface, and more specifically, the application relates to the device that contains solvent solution coating substrate surface.

Background of invention

The manufacturing of integrated circuit comprises to be transferred to the geometric configuration on the mask on the surface of semiconductor wafer.Afterwards, the regional corresponding semiconductor wafer between etching or the geometric configuration corresponding with geometric configuration.The transfer of geometric configuration from the mask to the semiconductor wafer is usually directed to lithographic plate printing method.This method comprises photosensitive prepolymer solution is applied to semiconductor wafer.Solvent in the prepolymer solution is removed by evaporation, then the thin polymer film of baking formation.Film by the photomask that supports desirable geometric scheme by radiant exposure, ultraviolet light for example.Then by wafer being immersed in the developer solution image developing with photochromics.According to the characteristic of photochromics, in developing process, remove exposure or unexposed area.Afterwards, wafer is positioned in the etching solution, and the zone that this solution will not protected by photochromics etches away.Because they are to the opposing of etching process, so photochromics is also referred to as photoresist.These materials can for example be to ultraviolet light, electron beam, x-ray, the perhaps material of ion beam sensitivity.

The expensive of photoresist prepolymer solution makes it wish that thereby the efficient of designing the raising coating process makes the polymer solution consumption reduce to minimum method.In addition, the thickness evenness of photoresist layer is an important criterion in the manufacturing of integrated circuit.It guarantees that geometric scheme reappears satisfactorily on the semiconductor wafer.

Solvent in the photoresist is easy to evaporation in application process, improved the viscosity of polymer solution, and suppressed the homogenising of the film of last formation.This causes in uneven thickness.Therefore, hope can be controlled the speed that solvent evaporates from polymer solution.

Ambient humidity is a factor that influences the photoresist layer thickness.Usually need 15 to 20 dusts and wafer ground of a wafer in the wafer, a collection of ground, from day to day the photoresist coating uniformity coefficient of 20 to the 25 dust orders of magnitude.This is less than the next influence of 1% relative humidity difference band.In addition, in the positive photoresist of the used usually photosensitive diazonium naphtoquinone compounds of employing, need the certain moisture and the product of photolysis reactions to react, generate needed water-soluble carboxylic acid.

Summary of the invention

The purpose of this invention is to provide a kind of method and apparatus that improves the thickness evenness of polymer solution, this polymer solution is applied to the surface such as the substrate of semiconductor wafer.

Another object of the present invention is to improve consumption, polymer solution such as the photoresist prepolymer solution of the polymer solution that is used for the substrate coating.

According to the present invention, a kind of method of utilizing polymer solution coating substrate surface is provided, comprise substrate is installed in the enclosed housing, make pilot-gas enter casing by inlet, polymer solution is deposited on the substrate surface in the casing, make the substrate spin, and discharge any solvent vapo(u)r and the granule foreign that suspends pilot-gas and the pilot-gas from casing by outlet.

Pilot-gas can be gas or the solvent-free gas that contains solvent vapo(u)r.

Discharging the step of pilot-gas and any solvent vapo(u)r and impurity can in the process, or carry out before deposition step afterwards.

The gas that contains solvent vapo(u)r is bubbled by solvent by gas usually and produces, and may further comprise the steps: the solvent steam concentration of controlling the gas that contains solvent vapo(u)r by the temperature of control solvent.The solvent steam concentration that contains the gas of solvent vapo(u)r can also mix with second kind of gas with different solvents vapour concentration and controls by the temperature of control casing or by containing solvent vapo(u)r gas.

Contain solvent vapo(u)r gas and generally include air or inert gas, as nitrogen.

Pilot-gas can enter casing by the shower nozzle divider that is located immediately at substrate top, thereby guarantee above wafer, to continue, controlled laminar airflow.

Polymer solution can comprise the photoresist polymkeric substance, for example, and the photic resist polymkeric substance of deep ultraviolet.

This method can may further comprise the steps: with temperature controlled solvent-free, and drying, filtered gas transfer is to coating substrate top.This method can also may further comprise the steps: solvent-free humid gas is delivered to coating substrate top; The humidity that can control humid gas makes it have the required relative humidity of polymer solution.Relative humidity remains in 40% to 50% the scope usually.The temperature of humid gas can also utilize the temperature and humidity controller to control.

Substrate is installed in step in the casing can comprises substrate is fixed to rotatable chuck, for example by between substrate and chuck, forming vacuum.

Substrate generally includes semiconductor wafer, and the solutes content in the polymer solution is 10wt% to 50wt% normally.

In addition, according to the present invention, a kind of apparatus for coating that utilizes polymer solution coating substrate surface is provided, this device comprises enclosed housing, be installed on the rotatable chuck that is used for supporting substrate in the casing, polymer solution is deposited to the precipitation equipment on the substrate surface in the casing, flowing with casing is connected the pilot-gas feeding mechanism that is used for to casing supply pilot-gas, and the discharger that links to each other with casing, be used for discharging pilot-gas and any solvent vapo(u)r and granule foreign from casing.

Precipitation equipment can comprise that being installed on chuck top is used for polymer solution flow is assigned to dispensing head device on the substrate surface, and this device can move with respect to substrate.If substrate has rounded basically shape, the dispensing head device can radially move basically usually and pass across substrate surface so.

Precipitation equipment also can comprise the film pressurizing unit, and this device has and is installed on chuck top and is used for polymer solution flow is assigned to extrusion head on the substrate surface.In this case, if the rounded basically shape of substrate, extrusion head is installed on the polymer solution flow that is used for radially extending above the chuck usually and is assigned to substrate surface so.

Adopt the specific embodiment of pressing method and device to be documented in United States Patent (USP) 6,191, in 053, this article all is incorporated herein by reference at this.In these embodiments, the material band is extruded by spirality pattern, the whole top of cover wafers.Wafer is installed on the chuck, horizontal aligument, upwards location.Because squeezing groove is radially aimed at respect to wafer, extrusion head is set at the adjacent wafer outer rim and is positioned at the wafer top surface top.When material is extruded squeezing groove, the rotation wafer, and extrusion head is moved radially towards center wafer.The rotating speed of control wafer and the radial velocity of extrusion head make extrusion head constant with respect to the tangential velocity of rotation wafer.

As mentioned above, rotatable chuck links to each other with variable-speed motor, and apparatus for coating can comprise the control device of control variable-speed motor speed.Casing can have upstream side and downstream; The gas supply device that contains solvent vapo(u)r can comprise the casing inlet that is installed on the casing upstream side, and discharger can comprise the outlet that is installed on the casing downstream.The pipeline that the pilot-gas feeding mechanism can comprise and casing flows to be connected, and at least one pipeline, be used for convection current and go into the speed of pilot-gas of casing and the electrically-controlled valve that each composition of pilot-gas is controlled.Discharger can also comprise that control discharges the valve gear of gas and any impurity from casing.The gas supply device that contains solvent vapo(u)r can comprise cleaning, drying, filtered gas source and the bubbler that flows and to be connected with casing.

Apparatus for coating may further include the temperature and humidity pilot-gas source of flowing and being connected with casing.Temperature and humidity pilot-gas source can comprise temperature control equipment and humidity conditioner, is used to control the temperature and humidity of the gas of being supplied by temperature and humidity pilot-gas source.

Description of drawings

Fig. 1 illustrates the cross-sectional schematic side view according to an embodiment of spin coating device of the present invention; And

Fig. 2 illustrates the cross-sectional schematic side view according to another embodiment of spin coating device of the present invention.

When Fig. 3 a illustrated fixedly roll rate, film thickness was as the function of solvent flow rate.

Fig. 3 b illustrates the function of film thickness as the flow of solvent time.

Fig. 4 illustrates the common film thickness profile that strides across wafer.

Fig. 5 is illustrated in the present invention and the comparison of film uniformity coefficient between the technology formerly.

Fig. 6 is illustrated in the present invention and the comparison of resist temperature range between the technology formerly.

Fig. 7 is illustrated in the present invention and the comparison of chill plate temperature range between the technology formerly.

Fig. 8 is the wiring layout of extrusion head side view of the present invention.

Fig. 9 is the front elevation of the header board of extrusion head of the present invention.

Figure 10 is the front elevation of the back plate of extrusion head of the present invention.

Figure 11 is the front elevation of the pad of extrusion head of the present invention.

Figure 12 is the front elevation of pad against the back plate.

Figure 13 is the viewgraph of cross-section of the extrusion head that assembles of the present invention.

Figure 14 is the skeleton view of the extrusion head that assembles of the present invention.

Figure 15 is the viewgraph of cross-section that has two limits of extrusion head of substrate, and substrate moves below two limits of extrusion head.

Figure 16,17 and 18 is respectively the front elevation that the present invention pushes spin coating device, top view and rear view.

Figure 19 is the block diagram that the present invention pushes an embodiment of control system in the spin coating device.

Figure 20,21,22 and 23 are illustrated in the structure of extruding spin coating device in the several steps that the present invention pushes spin coating method.

Figure 24 illustrates the diagram of pushing some parameters of spin coating campaign according to the present invention.

Figure 25 illustrates the spirality pattern according to extruding spin coating of the present invention.

Embodiment

The present invention relates to a kind of inhomogeneity method of formed coating thickness that solution deposition is improved on substrate the time.Further relate to the method that reduces this solution losses.Especially, this method with reference to the semiconductor wafer that is used for the integrated circuit manufacturing and photoresist prepolymer solution to semiconductor wafer surface should be used for describe.Be appreciated that the film or the coating that are used for the integrated circuit manufacturing are not limited to the photoresist layer, for example can comprise, anti-reflective film, siloxane spin-on-glass film, Kapton, and material such as Polyimidesiloxane film as organic planar film.

Before coating process, the above-mentioned solutes content in these materials is generally 10wt% to 50wt%.

Need carry out the coating process of semiconductor wafer in casing or chamber, described chamber permission atmosphere is wherein used in the solvent molecule saturated at least in part, and this can be clearer from following discussion.Its signal layer coating that has by form solvent on substrate surface has the advantage of improving cast film (cast film) wettability.In addition, by the solvent strength of control indoor gas, can improve the thickness evenness of polymer solution film on the substrate.This is to adopt rotational casting film (spin-cast film), the situation of spray-coated film (spray-coated film) or any other similar coating process.

In the rotational casting method, when substrate static, linear moving, or during rotation, solution is coated on the substrate.Substrate spin is afterwards scattered solution on its surface.After solution scattered on substrate surface, the solvent in the solution was removed by evaporation, stayed one deck solute on substrate surface.When sizes of substrate increases, perhaps attempt when making the Fluid Volume that is applied to substrate surface be kept to minimum to reduce cost, cause the in uneven thickness of solute zone on the substrate usually.To a certain extent, this part is the different result of tangential velocity between substrate edge and the center.Cause the inhomogeneous evaporation of solvent along the inhomogeneous air-flow at edge, produce the inhomogeneous of coating thickness thus.Because bigger substrate needs higher roll rate to obtain near the center uniformity coefficient, therefore with substrate edge near the contacted air of solution carry out inhomogeneous reaction and can cause helix and striped near the substrate edge.These features are called as the Ekman helix.

When using inadequate coating solution, also can encounter problems.When in the rotational casting process, attempting to be kept to minimum and to reduce cost, cause inhomogeneous because quantity of solvent is little by the coating solution amount that will be applied to substrate surface.In coating process, the evaporation of solvent causes various defectives and scrambling (irregularity).Equally, in spray-coated film, solvent is easy to evaporation in application process, has increased viscosity like this and has suppressed to form the homogenising of film, so caused in uneven thickness.

As mentioned above, some photoresists need the certain moisture and the product of photolysis reactions to react.For those reasons, hope can the pulpit in the humidity of air.

With reference now to the embodiment that uses spin coating method, describes the present invention in detail.In these embodiments, substrate is a semiconductor wafer, and the solution that is applied to semiconductor wafer is photoresist prepolymer solution.

Fig. 1 illustrates the embodiment according to the used spin coating of method of the present invention (spin-coating) device 10.Device 10 comprises the rotatable support chuck 12 that is installed in the enclosed housing 14.Chuck 12 extends to axle 16, and this passes the opening 18 in the casing 14.Casing 14 comprises the input end with the form of head-type divider (shower-head-like dispenser) 20.This allows pilot-gas, comprises that a kind of gas and certain density solvent pass and enter casing 14.Pilot-gas can be solvent-free gas or contain solvent gas, and can comprise air or inert gas, as nitrogen.Divider 20 is set directly at the substrate top that is placed on the chuck 12.Input channel 24 extends to an end of head-type divider 20.Temperature and humidity pilot-gas source (not shown) supply temperature and humidity are controlled air or nitrogen, and link to each other with pipeline 24 by pipeline 26.Second pipeline 28 will clean, dry, filtered gas source is introduced bubbler 21.Bubbler 21 is contained in the solvent tank 13 that solvent 15 is housed.Cleaning, dry, filtered gas generally include air or nitrogen, pass bubbler 21 formation and contain solvent gas, and this gas is guided pipeline 24 into by pipeline 3.Valve 9 is installed in the pipeline 26, and valve 11 is installed in the pipeline 3.Valve 9,11 makes the temperature and humidity pilot-gas and contains in the solvent gas one or both and flows to casing 14.Valve 9,11 normally is used for the electrically-controlled valve of automatic pilot-gas flow velocity and composition.By the control of heating/cooling coil, this coil pipe control is by the temperature of pipeline 28 or the gas supplied by solution 15 or by both by the temperature that contains solvent gas of bubbler 21 supply.Usually necessary heated solvent 15 compensates the thermal loss that causes because of evaporation.The temperature and humidity of temperature and humidity pilot-gas also utilizes special-purpose temperature and humidity controller to control, and this temperature and humidity controller comprises refrigeration unit, boiler, and temperature and humidity sensor.Also can control the temperature and humidity of temperature and humidity pilot-gas by the temperature and humidity controller that adopts the bubbler device.In a preferred embodiment, pipeline 26 is provided by two arm (not shown).This allows it to link to each other with bubbler or humidity Controlling Source.Bubbler is installed in the shell that comprises device 10 remaining parts usually.In contrast, special-purpose humidistat above-mentioned comprises independent structures.When humid gas was provided, relative humidity remained on the required level of polymer solution: usually between 40% and 45%.Apparently, humidity can remain zero under suitable environment.

Device 10 further comprises dispensing head 4, and this dispensing head is used for solution (in this case, solution is photoresist prepolymer solution) is dripped on the wafer 7 that is installed on the chuck 12.

A circular passage 6 has been determined in the bottom of casing 14, and this passage has the gas of being used for, as the exhaust apparatus 22 of air or nitrogen, and the drainpipe 27 that is used for liquid.

In common process, utilize any standard method, as the method that between chuck 12 and wafer 7, forms vacuum semiconductor wafer 7 is anchored on the chuck 12.Close the wafer transport door 2 of casing 14 afterwards.Utilize dry solvent-free gas purification casing 14.Then pilot-gas is sent into casing.Before coating solution is assigned to substrate, in the process, and after, the solvent strength of pilot-gas is controlled, by valve 9 and 11 is handled, solvent passes valve 11 along pipeline 3, enters casing 14 along pipeline 24.To comprise that by bubbler 21 the gas foaming of nitrogen or air can realize the may command dividing potential drop of solvent.Bubbler 21 in this embodiment comprises fritted glass material (porous glass frit), and by liquid solvent 15, solvent keeps suitable design temperature to gas from the fritted glass material.Before coating process and in the process, the solvent gas that contains that comprises the final formation of appropriate solvent concentration passes through above semiconductor wafer.Apparently, solvent tank 13 must hold or well-off solvent, to keep containing solvent strength desirable in the solvent gas.

For photoresist being deposited upon on the wafer 7, polymer solution is coated the surface of wafer 7 through dispensing head 4.This is by distributing the polymer solution of continuous stream to be achieved from nozzle 5 when wafer 7 spins with relatively low speed or be static.In a preferred embodiment, nozzle 5 radially moves basically and strides across wafer 7.In addition, solution also can be distributed in substrate center, perhaps can use a plurality of nozzles.By adjusting the roll rate of wafer 7, the speed that the motion of nozzle 5 and polymer solution distribute can obtain suitable solution and distribute.In another embodiment, as shown in Figure 2, when wafer rotates with a rotary body (one fu1l tum), by film extruder 23 polymer solution is deposited on the wafer, this film extruder is a common extruder well known in the art.Extruder 23, with the thin film deposition of polymer solution on wafer 25.If wafer to be coated is not rounded basically, wafer vertically moves usually in the polymer solution deposition step so.

Because the extruder method is identical with Fig. 1 embodiment in other respects, therefore with reference to figure 1 this method of explanation.After wafer 7, the roll rate of wafer 7 increases at solution deposition, so that the solution dispersion is crossed the upper surface of wafer 7.To contain solvent gas and contain any granule foreign that suspends in the solvent gas and discharge, before coating wafer 7 and in the process, can form uniform one deck photoresist prepolymer solution at the upper surface of wafer 7 through exhaust apparatus 22.Afterwards, change the solvent-free gas of temperature and humidity control through the gas of pipeline 24 inlet chambers into by valve 9 and 11, as air or nitrogen.Valve 9 and 11 is controlled by the microprocessor (not shown) usually.Reduce the solvent strength in the pilot-gas then, the temperature of the pilot-gas that perhaps raises, thus remove more multi-solvent in the polymer solution that is deposited on the wafer 7.Usually, supply solvent-free gas, to add the evaporation of strong solvent from polymer solution to casing.When forming sufficiently rigid photoresist layer when producing desirable evaporation capacity, wafer 7 is stopped, the wafer transport door is opened, and the wafer of coating shifts out from casing 14.As mentioned above, in the different stages, gas is discharged from casing 14 through exhaust apparatus 22, and described gas can be dry or moist, and is solvent-free or contain solvent gas.Like this, guiding gas is crossed wafer 7, from the upstream extremity that is positioned at shower nozzle divider 20 to the downstream end that is positioned at exhaust apparatus 22.Waste gas stream is controlled by valve 8, controls the gaseous tension in the casing 7 thus.Valve 8 is usually with the control of microprocessor (not shown).Any polymer solution of dishing out comprises granule foreign, is collected in the circulating line 6, discharges through drainpipe 27.

As mentioned above, it is adjustable supplying with the liquid solvent of bubbler 21 or the temperature of gas.Like this, can regulate the dividing potential drop that contains solvent in the solvent gas.This realizes by using above-mentioned heating/cooling coil.Concentration can be regulated by the gas that increase contains different solvents concentration in addition.This gas can provide through the pipeline (not shown) that links to each other with pipeline 3.Apparently, if bubbler is identical with the temperature of casing 14, it is saturated in solvent to contain solvent gas so.If the temperature of bubbler is high slightly, contain the solvent gas supersaturation in the casing 14 so, if the temperature of bubbler is low slightly, so in the casing 14 to contain solvent gas unsaturated.Usually containing solvent gas is provided by bubbler 21, and casing 14 keeps identical temperature to keep solvent saturated.As mentioned above, device 10 is installed in the shell (not shown) usually.Shell is temperature controlled, maintains common 22 ℃ temperature in order to the parts with shell and device 10.

Usually, the solvent that contains of the solvent that comprises in the bubbler and gas be deposited on wafer on solution in contained solvent identical.Equally, if solution contains more than a kind of solvent, bubbler can comprise the similar solvent of same ratio so.Yet the solvent that uses in bubbler is inequality with the solvent in the solution that is deposited on the wafer to be desirable under a stable condition.

Know, can utilize the technology that is different from bubbler to produce and contain solvent gas.

Utilize isoteniscope can accurately determine the steam pressure of solvent.In addition, by inert gas being passed solution example and measuring the quantity of solvent as the function of time of removing when analyzing by weight, can accurately determine steam pressure.Can regulate the solvent partial pressure in the gas of pipeline 3 supply, preferably be adjusted into the equilibrium vapor pressure that produces corresponding to solvent in the polymer solution.Guarantee that like this solvent equals the speed of film lyosorption from gaseous environment from the speed of deposited film or coating evaporation.

As mentioned above, the solvent partial pressure in the casing 14 can be regulated by the temperature of control bubbler or gas.In addition, the gas that contains different solvents concentration can mix with the solvent saturated gas.Solvent partial pressure optimal curve as the function of time in coating process is rule of thumb determined in the casing atmospheric pressure.

In coating process, contain solvent gas or humid gas by exhaust apparatus 22 continuous discharges, can regulate humidity and solvent partial pressure in the casing at an easy rate, thereby guarantee uniform solution layer thickness on semiconductor wafer surface.Equally, can eliminate solvent from being deposited on the influence of the polymer solution premature evaporation on the wafer 7.The polymer solution that this allows to use still less reduces cost thus.

Working example

I. spin coater (spin coater):

Spin coating device assembles and is installed in wafer track (track) machine by the size that is applicable to 200mm diameter wafer.In the wafer process process, carry out original position air pressure, temperature, the measurement of relative humidity and concentration by volume.Ethyl lactate is as the casting solvent (castingsolvent) of photoresist.Solvent strength in the process chamber changes between the 0-40% of saturation value.

Fig. 3 a and 3b illustrate by implementing the result that method of the present invention obtains.Shown in Fig. 3 a and 3b, the change of final film thickness is by the control solvent evaporation rather than depends on roll rate.In the limit of zero solvent flow rate, velocity of evaporation is the highest, because of the paired characteristic of convection current and evaporated material transport mechanism produces the thickest film.When solvent flow rate increased, velocity of evaporation reduced, and resist film is spread and the continuation attenuation through one section convection current than the long time.Therefore, implementing the present invention can change final film thickness when fixing roll rate 2000rpm

Shown in Fig. 3 a.Similarly, the flow of solvent time also can influence final film thickness, shown in Fig. 3 b.These data clearly illustrate that turbulent obstacle (turbulence wall) problem of inventing to the 300mm substrate provides a kind of solution.By implementing the present invention, roll rate can remain on below the 2000rpm, and by optimizing two new technological parameters, solvent strength and flow of solvent time, can obtain wider useful thickness.

Fig. 4 illustrates the wafer uniformity coefficient.

1 σ uniformity coefficient can obtain routinely, as recording by high spatial resolution measured film thickness instrument.

The uniformity coefficient result of the box wafer that Fig. 5 will process according to the present invention and the uniformity coefficient result of conventional coating machine make comparisons.These results show that the present invention reduces to minimum with the influence of turbulent obstacle, and can produce the wafer than the tightr uniformity coefficient control of conventional coating machine.

Fig. 6 will be according to the resist temperature range of work of coating machine of the present invention and comparing of conventional coating machine.With according to of the present invention

Compare, the resist temperature control that is used for 1 σ uniformity coefficient of conventional coating machine is (both all use the SPR508 resist).This expression resist temperature range has improved 36%.

Chill plate (wafer) temperature control that Fig. 7 illustrates 1 σ uniformity coefficient of conventional coating machine is

The present invention is reduced to The CP temperature range increases 43%.

In a word, The above results shows that when enforcement was of the present invention, the film profile reduced for the dependence of the relevant technological parameter of steam.This is the direct result that suppresses evaporation in the critical phase (critical phases) in spin coating, and this expression implements the invention solves two subject matters relevant with the 300mm substrate.

Although specific embodiment provides above-mentioned advantage, apparent, the invention is not restricted to the foregoing description.For example, pipeline 28 can directly link to each other with pipeline 3.Like this, also can supply bubbler 21 by the gas of temperature and humidity Controlling Source supply.When supply bubbler 21, the humidity of temperature and humidity Controlling Source can be reduced to zero simply.When dry or moist gas during, can close the valve in the pipeline 28, thereby guarantee to have solvent to be drawn onto in the pipe first 28 to casing 14 supplies.

Should be noted that when using some advanced deep UV photo anti-corrosion agent materials, can use anhydrous casting environment.Therefore, the humidity of temperature and humidity pilot-gas remains zero.

II. extrusion coating machine (extrusion coater):

The invention is not restricted to spin coating embodiment.For example, many embodiment adopt extrusion coated.One group of certain embodiments is used squeezing groove to apply the photoresist strip is distributed on the whole surface of wafer.Squeezing groove coating is to measure a kind of in these class methods of coating in advance.Utilize squeezing groove coating, coating thickness can be controlled by the photoresist dispensing rate, and efficient can be near 100%, and the thickness uniformity coefficient is very good.

In the squeezing groove coating, photoresist is expressed on the wafer by narrow groove.Fig. 8-15 illustrates the embodiment of the extrusion head 30 that can be used among the present invention.Extrusion head 30 also can be called extrusion die.Fig. 8 illustrates the side wiring layout of extrusion head 30, and extrusion head 30 is made of Stainless Steel U pad 31, and plate 33 was middle after this pad 31 was clipped in stainless steel header board 32 and stainless steel.Fig. 9,10 and 11 illustrate header board 32 respectively, the front elevation of back plate 33 and pad 31.Figure 12 illustrates the front elevation of pad 31 against back plate 33.With reference to figure 8, place header board 32 and back plate 33, and polish its inner edge towards pad 31, so that the sealing good with pad 31 to be provided, and the smooth surface that is used to push.Photoresist enters extrusion head 30 by the port 34 at plate 33 tops, back.Port 34 guides to flow channel 36 (Fig. 8,10) with photoresist by managing 35.The opening 37 the same wide (Figure 11,12) of " U " shape of flow channel 36 and pad 31.

Figure 13 is the sectional view of extrusion head 30 shown in Figure 8.The hole that the u shape of pad 31 is produced stays next close clearance 38 between header board 32 and back plate 33, photoresist flows out by this close clearance.In the bottom of extrusion head 30, continue between two narrow " limits " 41,42 downwards in gap 38, and these two limits make the inside surface elongation of header board 32 and back plate 33.

Figure 14 is the skeleton view of extrusion head shown in Figure 8.Pad 31 " U " shape opening 37 (Figure 11,12) are crossed in gap 38, thereby form squeezing groove 39 in extrusion head 30.

Figure 15 is two limits 41,42 of extrusion head 30 and the viewgraph of cross-section of substrate 50, and substrate 50 moves under squish lip 41,42.Photoresist is expressed on the end face 51 of substrate 50 from the groove 39 of 41,42 bottoms, two limits.The width in the gap 38 between header board 32 and the back plate 33 is represented with d, equals the thickness (Fig. 8,13) of pad 31.Coating gap between limit 41,42 and the substrate 50 has been full of the globule from the coating fluid of groove 39.When substrate 50 moves perpendicular to groove 39, keep the coating gap constant, fluid is pulled out globule 46, is retained on the substrate 50 as film.The width w of cast film (Figure 23,24) approximates the length of squeezing groove 39, that is, and and the opening (Figure 11,12) of " U " shape of pad 31.The average thickness h of cast film is

$h=\frac{Q}{\mathrm{wv}}$

Wherein v is a coating speed, and Q is the fluid dispensing rate.Meniscus (meniscus) 44,45 at coating pearl 46 forward positions and place, edge, back is fixed to the turning on two limits 41,42 of extrusion head.The turning on two limits 41,42 of extrusion head should have the radius-of-curvature less than about 50m, thereby keeps meniscus 44,45 fixing.Coating capillaceous in the pearl 46, viscosity, inlet pressure must the balance external pressure, to keep the stability of coating pearl 46.During when the thinner film of coating or with higher coating speed coating, the low vacuum in coating pearl 46 forward positions can be used for making coating pearl 46 stable.Two limits 41,42 of extrusion head have equal lengths (G usually ₁=G ₂), extrusion head 30 is perpendicular to substrate 50.Yet, one of sometimes make in two limits to extend beyond another side (G for extremely thin coating ₁#G ₂), the direction that perhaps makes extrusion head 30 tilt to depart from perpendicular to substrate 50 slightly is useful, and coating pan 39 is tilted with respect to substrate 50.

With reference to Figure 16,17 and 18 describe extruding spin coating device 100, Figure 16, and 17 and 18 illustrate the front elevation according to extruding spin coating device 100 of the present invention respectively, top view and rear view.Figure 16, the parts of the extruding spin coating device 100 shown in 17 and 18 comprise coating module 110 and positioning system 130.Control system 210 is at Figure 16, and is not shown in 17 and 18, but can describe with reference to Figure 19, and this control system 210 comprises register control 220 and spinner controller 280.

Coating module 110 comprises spinner device 111, and this device comprises the spinner servomotor (not shown, the reference number 113 among Figure 19) that links to each other with vertical shaft 112.Vertical shaft 112 supports teflon vacuum chuck 114.Utilize chuck lifter servomotor (not shown, the reference number 115 among Figure 19), spinner device 111 can vertical moving.Chuck lifter servomotor is furnished with elevator motor lock (not shown, the reference number 135 among Figure 19).When spinner device 111 is positioned at its extreme lower position, chuck 114 by collection cups (catch cup) 116 (xsect illustrates) around.Collection cups 116 is the circular cup with open top 117.The top 120 of wall of cup 118 slopes inwardly, and keeps photoresist unnecessary in the collection cups 116 easily.Collection cups 116 has three functions.Collection cups 116 holds and unnecessary photoresist is discharged to waste liquid drainpipe 122 outsides.Collection cups has a vent port 118, and the solvent of evaporation is discharged from this vent port.Air-flow on the collection cups 116 guiding rotation wafers is to avoid occurring turbulent flow.Vent port 118 and waste liquid drainpipe 122 stretch out the bottom 124 of collection cups 116.Be used to discharge unnecessary photoresist and it is well known to those having skill in the art that, therefore no longer illustrate with the device of the steam of crossing.

Spinner device 111 has centring means, comprises eight teflon pins 138, is used for the center of wafer orientation in chuck 114, and spinner device 111 also has three normal pin (not shown), is used to support the not fastening wafer in processing front and back.Centring pin 138 is by centering solenoid (not shown, the reference number 119 among Figure 19) control.The original position that the sensor indicate chuck 114 of coating on the module 110 is vertical is (not shown, reference number 121 among Figure 19), vacuum state (ON/OFF) (not shown, the reference number 123 among Figure 19), centring pin position (not shown, the reference number 125 among Figure 19).These features of coating module 110 it is well known to those having skill in the art that, therefore no longer illustrate.

Being fit to the coating module 110 that the present invention uses is 90SE coating modules, can be on market from Silicon Valley Group, and Inc obtains.90SE coating module is parts of 90SE wafer process track (track), also can be on market from Silicon Valley Group, and Inc obtains.

Positioning system 130 is supported by aluminum soleplate 132, and base plate is installed in coating module 110 tops.Base plate 132 has a center cut 134 that is positioned on the coating module 110.First and second vertical support panel 134,136 are installed on the base plate, support to intersect and prop up a part (cross-support) 137, and diaxon positioning system 150 is installed in to intersect and props up on the part 137.Positioning system 150 comprises x axle positioning table 152 and z axle positioning table 162.X axle positioning table 152 comprises x axle worktable motor 154 and x axle table base 156.Equally, z axle positioning table 162 comprises z axle worktable motor 164 and z axle table base 166.Z axle positioning table 162 also comprises z shaft brake (not shown, the reference number 133 among Figure 19).Z axle positioning table 162 is installed on the support 158 of x axle positioning table 152.X axle positioning table 152 moves in surface level, is parallel to the surface 51 of the wafer 50 that is installed on the chuck 114, and z axle positioning table 162 moves along the vertical direction perpendicular to the plane, 51 place, surface of wafer 50, and described wafer 50 is installed on the chuck 114.The positioning system that is suitable for x axle of the present invention and z axle positioning table 152,162 is the Parker DaedalMotion Table that 5 tooth pitch ball-screws drive.

Extrusion head 30 is installed in the bottom of aluminum extrusion head support 172, and support 172 is installed on the z axle positioning table 162.Z axle positioning table 162 has enough range of movement, and mobile extrusion head 30 is passed down through the center cut 134 on the base plate 132 from the position of base plate 132 tops, arrive wafer 50 on the chuck 114 near.

Optical sensor 174 is installed on the extrusion head support 172.Optical sensor 174 is used to measure extrusion head 30 and is installed in gap between the wafer 50 on the chuck 114.Be applicable to that the sensor in the embodiment of the invention is a Philtec RC 140L reflectance compensate for optical displacement transducer.Optical sensor 174 on wafer 50 surfaces, is measured reflected light with rayed, and generation and the proportional voltage of measured light intensity.The spot size of Philtec sensor is 6mm, and the bandwidth of its direct current DC is 100Hz.Voltage one distance Curve of Philtec sensor is normally nonlinear, but when sensor one wafer distance for example 5.51 and 6.17mm (0.217 and 0.243 inch) between the time curve have the range of linearity.Optical sensor 174 is positioned on the extrusion head support 172, makes all measured values drop in the range of linearity of optical sensor 174.

The device that the control photoresist flows comprises photoresist pump (not shown) and photoresist intercepting valve 129.These devices it is well known to those having skill in the art that, therefore at Figure 16, all do not illustrate in 17 or 18.Yet the following description of the control system 210 of extruding spin coating device 100 is with reference to photoresist pump (not shown, the reference number 127 among Figure 19) and photoresist intercepting valve 129.

Figure 19 is a block diagram, and it illustrates the embodiment of the control system 210 that is suitable for controlling extruding spin coating device 100 of the present invention.Control system 210 comprises computing machine 212, register control 220 and spinner controller 280.Computing machine 212 is through serial line interface 213,214, and 215 download to register control 220, spinner controller 280 and photoresist proportioning pump 127 with program.Register control 220 sends a command to photoresist proportioning pump 127, makes photoresist mobile (photoresist flow) begin and stop, and control photoresist intercepting valve 129.Register control 220 is also controlled the position of x axle positioning tables 152 by x axle motor 154, by the position of z axle motor 164 control z axle positioning tables 162, and chuck lifter servomotor 115.Register control 220 receives the output of optical sensor 174, calculates the distance between extrusion head 30 and the wafer 50, and utilizes the result to pass through z axle motor 164 control z axle positioning tables 162.

The computing machine that is suitable for control system 210 is an ibm compatible personal computer.What be suitable as register control 220 is Parker Compumotor AT6450 Servo controller, comprises selectable ANI analog input PC engaging AUX plate.That be suitable as spinner controller 280 is Pacific Scientific SC 755.Although in the embodiment that comprises Parker Compumotor AT6450 and Pacific Scientific SC 755 controllers, computing machine 212, register control 220 and spinner controller 280 illustrate respectively in the block diagram of Figure 19, but CompumotorAT6450 also can be inserted into plug in the motherboard of PC.The present invention also considers such an embodiment, and in this embodiment, the function of register control 220 and spinner controller 280 is provided by an independent general controller.

Register control 220 comprises register control processor and several input and output.Input and output comprise 14 moduluses (A/D) converter, several discrete digital input and output, and servomotor output (processor and input and output it is well known to those having skill in the art that, illustrate no longer separately).The output terminal of optical sensor 174 is connected to A/D converter input 224.Register control 220 discrete numeral inputs are optoisolated interfaces, comprise the chuck position calling indicator input 242 that links to each other with chuck position internal sensor 121; The vacuum opening/closing positioning indicator input 244 that links to each other with vacuum opening/closing sensor 123 on the vacuum chuck 114; Go into/go out position indicator input 246 with the centring pin that centring pin position transducer 125 links to each other; And the one or more artificial positioning command input 248 that links to each other with the artificial positioning switch 126 of operator.

Register control 220 outputs comprise the x axle servomotor output 226 that links to each other with x axle servomotor 154; The z axle servomotor output 228 that links to each other with z axle servomotor 164; And the elevator motor that links to each other with lifter servomotor 115 output 230.

The output of register control 220 discrete digital comprises the photoresist valve ON/OFF output 254 that links to each other with photoresist intercepting valve 129; The centering solenoid output 256 that links to each other with the centering solenoid 119 of control centring pin 138; The vacuum solenoid output 258 that links to each other with vacuum solenoid 131; The z axle motor brake output 260 that links to each other with z shaft brake 133 in the z axle positioning table 162; The elevator motor detent output 262 that links to each other with elevator motor detent 135; The trigger output 264 of photoresist proportioning pump 127; And the logic of spinner controller 280 output 266.

The signal that 280 pairs of register controls 220 of spinner controller receive responds and moves coating and self-rotary cycle.Spinner controller 280 comprises the spinner controller processor, servomotor output, and scrambler (processor and scrambler it is well known to those having skill in the art that, illustrate no longer respectively).The output of spinner controller 280 comprises the spinner motor output 286 that links to each other with spinner motor 113.The output of spinner controller 280 also comprises the analog encoder signals 288 that links to each other with register control.Analog encoder signals 288 makes the x axle location of the electromagnetic gear control of spinner motor 113 speed by the extrusion head 30 of register control 220 execution.

Extrusion head 30 and positioning table 152,162 must be aimed at respect to the wafer 50 that is installed on the chuck 114, to obtain reliable coating.Need three alignings.These three alignings are with reference to Figure 16, and 17 and 18 describe.The path that first aim to adjust squeezing groove 39, the center of the wafer 50 that squeezing groove 39 is directly passed be installed on the chuck 114.This aligning needs the central area of complete cover wafers 50.Extrusion head 30 is positioned the top, center of wafer 50 by front and back slip vertical support panel 134,136 on base plate 132.The motion of vertical support panel 134,136 is subjected to the restriction of base plate 132 upper rails.Before vertical support panel 134,136 was fastened to the appropriate location, the adjustment bolt at each vertical support panel 134,136 rear portion carried out accurate adjustment to their position.

Aim at for second and adjust the angle of x axle with respect to wafer surface 51.This is aligned in when x axle positioning table 152 changes the position and keeps the gap between wafer 50 and the extrusion head 30 constant.Rotate an intersection part 138 by first pivot 179 and can change the angle of x axle with respect to wafer surface 51 around intersection part 137 1 end.When accurate adjustment and coarse adjustment bolt 184,186 allowed accurate adjustment bolt 184 whenever to circle, the angular setting between x axle and the wafer surface 51 was 1.64x10 ^-5Radian.The x axle can be determined with optical sensor 174 scanning wafer surface 51 with respect to the angle of wafer surface 51.In scanning process, the z axle is fixed, the measured value of output optical sensor 174, and record x position.The linear regression that these data are right provides the angle between wafer surface 51 and the x axle.

Aim at the lower edge of adjusting extrusion head 30 for the 3rd, promptly squeezing groove 39, and is parallel with wafer surface 51 with the x axle up to it.This aligning is constant for the gap that keeps striding across extrusion head 30 width to be vital.Angle between the lower edge of extrusion head 30 and the x axle is utilized the wafer extruder depth of parallelism to adjust bolt 176 and is adjusted.Wafer extruder depth of parallelism adjustment bolt 176 is adjusted pivot 178 with respect to the wafer extruder depth of parallelism of z axle positioning table 162 bottoms and is installed on extrusion head support 172 rotatably.Angle between x axle and extrusion head 30 bottoms can utilize linear variable difference transformer (LVDT) sensor to measure.The LVDT sensor is fixed in wafer surface 51, and measures most advanced and sophisticated vertical points upwards.Then, extrusion head 30 descends, and moves the LVTD sensor up to two limits 41,42 of extrusion head 30 and arrives the reference position.After the position of record x axle and z axle positioning table 152,162, repeat this program for several other positions along two limits 41,42 of extrusion head.Extrusion head 30 utilizes these data with respect to the slope of x axle, and right linear regression is determined.

Optical sensor 174 can be proofreaied and correct by two step processes.At first, by utilizing the accurate pad between extrusion head 30 and wafer surface 51, measure at the output voltage of several little clearance distance place optical sensors 174 and determine variation (being that the zero stand-off is offset) voltage.The linear regression analysis of clearance distance and sensor voltage data is used for calculating voltage skew (that is the sensor voltage at place, zero stand-off).Secondly, in the range of linearity of optical sensor 174, the relation of sensor voltage and squeezing groove 39 height is determined by the sensor voltage that improves squeezing groove 39 by selected increment (for example, 10 encoder to count equal 12.7 μ m) and write down each position.The linear regression that data are right provides slope of a curve, and described curve representative sensor voltage is to the z shaft position of squeezing groove 39.As mentioned above, before collimation optical sensor 174, extrusion head 30 must be aimed at respect to x axle and wafer surface, thereby makes the angle between extrusion head 30 and the wafer surface 51 can not cause error.

With reference to figure 20-23 explanation extruding spin coating method.Above-mentioned aligning and correction program can periodically carry out, perhaps must determine and a series of flow processs based on the experience of device therefor before.

With reference to Figure 20, rising vacuum chuck 114 passes the otch 134 of base plate 132, and wafer 50 is positioned on the chuck 114.Utilize centring pin 138 (Figure 17) wafer 50 to be positioned the center of chuck 114.Open chuck vacuum (not shown) with fixed wafer 50.Reduce chuck 114, wafer 50 is dropped to the coating position, extrusion head drops to the position at wafer 50 edges, forms desirable gap as shown in figure 21 between wafer 50 and two limits 41,42 of extrusion head.Chuck is pressed the initial speed rotation then, and described initial speed is desirable coating speed.Open photoresist intercepting valve 129, thereby and trigger photoresist pump 127 and begin to distribute photoresist.Extrusion head 30 moves radially with respect to wafer 50.When extrusion head 30 when move at wafer 50 centers, improve the rotating speed of chuck 114, constant for the coating speed of the wafer 50 that keeps extrusion head 30 tops, extrusion head speed improves according to increasing proportional ratio with rotating speed.When the center of the forward position of extrusion head 30 arrival wafer 50, as shown in figure 22, it is constant that the rotating speed of wafer 30 keeps, up to the back center along arrival wafer 50 of extrusion head 30.When entire wafer 50 applied photoresists, trigger photoresist pump 127 stopping to distribute photoresist, and close photoresist intercepting valve 129.Usually,, need to continue the extruding photoresist, and continue mobile extrusion head 30, arrive the center of wafer 50 up to the back edge of extrusion head 30 for entire wafer 50 is covered photoresist.When triggering photoresist pump 127 and intercepting valve 129 and stop to distribute photoresist, the photoresist surplus in extrusion head 30 (may also lead in the pipeline of extrusion head 30) can continue to flow out and be deposited on the wafer 50.In this case, can before covering entire wafer 50, trigger photoresist pump 127 and intercepting valve 129, stop to distribute photoresist in order to the short time, make this residue photoresist stop cover wafers 50 thus.

Chuck 114 is reduced to wafer 50 in the collection cups 116 then, and extrusion head 30 rises from dispensing area, as shown in figure 23.Wafer 50 spins to remove excessive photoresist, the coating uniformity coefficient of realizing ideal at a high speed then.Chuck 114 stops spin, the center cut 134 that rises and pass base plate 132.Close vacuum, wafer 50 is removed from chuck 114.

Figure 24 is the diagram that illustrates according to some parameters of extruding spin coating campaign of the present invention.In Figure 24, wafer 50, radius are R, rotate with angular velocity Ω around its center.Extrusion head 30 is above wafer 50, and squeezing groove 39 is radially aimed at respect to wafer 50.Squeezing groove 39 has width w, moves radially with speed u with respect to wafer 50.Distance between wafer 50 centers and the edge, extrusion head 30 back is r.

As shown in figure 24, wafer 50 surface is gone up the tangential velocity apart from any point at turning axle r place and is:

v＝Ωr

Because the back edge of extrusion head 30 is at distance turning axle r place, move inward the length of a squeezing groove 39 by wafer 50 extrusion head that whenever circles, can form spiral compression pattern.Extrusion head 30 along the speed of wafer 50 diameters is so:

$u=\frac{\mathrm{\Ωw}}{2\mathrm{\η}}$

Obtain Ω and substitution obtains:

$u=\frac{\mathrm{wv}}{2\mathrm{\πr}}$

For radially inwardly motion, u=-dr/dt, the differential equation of extrusion head position can obtain following formula:

$\frac{\mathrm{dr}}{\mathrm{dt}}=\frac{\mathrm{wv}}{2\mathrm{\πr}}$

Starting condition r=r during with t=0 ₀Ask the integration of this equation to obtain:

$r={({\mathrm{<figure-callout\; id="0"\; label="r"\; filenames="H2006101005169E00032.png"\; state="\{\{state\}\}">r</figure-callout>}}_0^2-\frac{\mathrm{wvt}}{\mathrm{\&pi;}})}^{1/2}$

Wafer rotation can be expressed as the function of time:

$\mathrm{\&Omega;}=\frac{v}{{({\mathrm{<figure-callout\; id="0"\; label="r"\; filenames="H2006101005169E00032.png"\; state="\{\{state\}\}">r</figure-callout>}}_0^2-\frac{\mathrm{wvt}}{\mathrm{\&pi;}})}^{1/2}}$

Extrusion head speed can be expressed as the function of time:

$u=\frac{\mathrm{wv}}{2\mathrm{\&Pi;}{({\mathrm{<figure-callout\; id="0"\; label="r"\; filenames="H2006101005169E00032.png"\; state="\{\{state\}\}">r</figure-callout>}}_0^2-\frac{\mathrm{wvt}}{\mathrm{\&pi;}})}^{1/2}}$

Figure 25 illustrates the extruding spin coating spirality pattern 202 according to one aspect of the invention.Spirality pattern 202 is produced towards the inside radial motion in the center of wafer 50 by outer rim 52 beginnings of extrusion head 30 at wafer 50.The unnecessary photoresist in 204 expression wafer 50 outer rim places, first shadow region, the photoresist of the double-thickness that second shadow region, 206 expression wafers, 50 central area extrude.Begin this process in the time of need just leaving the outer rim 52 of wafer 50 with extrusion head 50,, and need around the outer rim 52 of wafer 50, not superpose or have double-thickness so that cover whole outer rim 52 with the spirality pattern 202 of extruding.This produces first shadow region 204 of unnecessary photoresist.Equally, after arriving wafer 50 centers, the forward position of extrusion head 30 needs to continue to extrude photoresist, up to covering entire wafer 50.Usually, need to continue this process, back up to extrusion head 30, thereby the whole central area of cover wafers 50 along the arrival center.Because the finite width of extrusion head 30, the stack in second shadow region 206, wafer 50 centers is inevitable.Yet unnecessary amount with excessive photoresist is relative less, and the efficient of extruding spin coating method outclass the efficient of previous spin coating method.

Figure 25 illustrates the spirality pattern of extruding spin coating, and this pattern makes extrusion head begin at wafer outer rim place when being spinned by wafer, inwardly move radially and form towards center wafer.Method and apparatus of the present invention also can make extrusion head begin in the center of wafer, moves towards wafer outer rim outward radial.

Obviously, the present invention is not limited to the foregoing description for a person skilled in the art.Different structure and embodiment can derive out, and can not depart from the scope of the present invention, and are included in the scope of claims.

Claims (50)

1. method of utilizing polymer solution coating substrate surface, this method comprises:

Substrate is installed in the enclosed housing;

To contain solvent polymeric thing solution is expressed on the substrate; And

Control the evaporation of solvent from polymer solution by adjusting the quantity of solvent of introducing in the casing environment, wherein adjusting the quantity of solvent of introducing in the casing environment comprises: the multiple gases that has the different solvents vapor partial pressure by mixing forms pilot-gas, thereby adjusts the degree of saturation of introducing the pilot-gas in the casing environment.

2. according to the process of claim 1 wherein that described substrate is to have end face, the wafer of center and outer rim; And

Wherein extruded polymer solution comprises and extrudes the photoresist band, described band has width, described band is with the whole top of spirality pattern covering substrate, wherein photoresist is extruded from squeezing groove with constant extrusion speed, substrate rotates with a rotating speed, extrusion head moves with a radial velocity, and the extrusion head that moves radially with respect to the substrate that rotates is with constant tangential velocity motion.

3. according to the method for claim 2, wherein the photoresist band is extruded with spirality pattern, begins in the wafer outer rim, finishes in center wafer.

4. according to the method for claim 2, wherein the photoresist band is extruded with spirality pattern, begins in center wafer, finishes in the wafer outer rim.

5. according to the method for claim 2, wherein the width of photoresist band wafer diameter 1/10th and 1/3rd between.

6. according to the process of claim 1 wherein:

Described substrate is to have end face, center, the wafer of diameter and outer rim;

Described substrate is installed in the enclosed housing, comprises wafer is installed on the chuck, the end face horizontal aligument of wafer is also upwards located; And

Extruded polymer solution comprises:

Extrusion head is arranged on the adjacent wafer outer rim and is positioned at the wafer top surface top, extrusion head is configured to photoresist is extruded squeezing groove, squeezing groove has the length that is limited by first end and second end, the mode of radially aiming at respect to wafer with squeezing groove is provided with extrusion head, first end of squeezing groove is arranged on the adjacent wafer outer rim, second end of squeezing groove is in the outside of wafer outer rim

Make wafer around its center rotation, wherein wafer rotates with a rotating speed, and extrusion head moves with a radial velocity, and the extrusion head that moves radially with respect to rotating wafer is with constant tangential velocity motion;

Extrude the photoresist band from squeezing groove, the width of described band equals the length of groove, and wherein photoresist is extruded from squeezing groove with constant extruder rate, and

Extruding photoresist from squeezing groove, and when keeping squeezing groove radially to aim at, inwardly moving radially extrusion head from the wafer outer rim towards center wafer, up to the whole top of photoresist cover wafers with respect to wafer.

7. according to the method for claim 6, wherein the length of squeezing groove the semiconductor wafer diameter 1/10th and 1/3rd between.

8. according to the method for claim 6, wherein keep squeezing groove radially to aim at and further comprise even maintenance squeezing groove certain distance above wafer top surface with respect to wafer.

9. method according to Claim 8 wherein keeps squeezing groove radially to aim at respect to wafer and further comprises the distance of determining between squeezing groove and the wafer top surface, and the position of adjusting squeezing groove is to keep this distance.

10. according to the method for claim 9, wherein keep squeezing groove radially to aim at and further comprise with optical sensor and determine distance between squeezing groove and the wafer top surface with respect to wafer.

11. according to the method for claim 6, wherein the photoresist band is coated on the wafer with the spirality pattern of the whole top of cover wafers.

12. the method according to claim 11 may further comprise the steps:

Remove extrusion head, and

The high speed rotating wafer.

13. according to the process of claim 1 wherein:

Substrate is to have end face, center, the wafer of diameter and outer rim;

Substrate is installed in the enclosed housing, comprises wafer is installed on the chuck; And

Extruded polymer solution comprises:

Extrusion head is arranged at center wafer and is positioned at the wafer top surface top, extrusion head is configured to photoresist is extruded squeezing groove, squeezing groove has the length that is limited by first end and second end, the mode of radially aiming at respect to wafer with squeezing groove is provided with extrusion head, first end of squeezing groove is positioned at center wafer, second end of squeezing groove is between center wafer and wafer outer rim

Make wafer around its center rotation, wherein wafer rotates with a rotating speed, and extrusion head moves with a radial velocity, and the extrusion head that moves radially with respect to rotating wafer is with constant tangential velocity motion;

Extrude the photoresist band from squeezing groove, the width of band equals the length of groove, and wherein photoresist is extruded from squeezing groove with constant extruder rate, and

Extruding photoresist from squeezing groove, and when keeping squeezing groove radially to aim at, moving extrusion head towards wafer outer rim outward radial, up to the whole top of photoresist cover wafers with respect to wafer.

14. adjust the equal uniform flow that position that quantity of solvent in the casing environment further is included in substrate end in the casing forms pilot-gas according to the process of claim 1 wherein, this equal uniform flow is substantially perpendicular to substrate.

15. according to the method for claim 2, wherein adjust the equal uniform flow that position that quantity of solvent in the casing environment further is included in substrate end in the casing forms pilot-gas, this equal uniform flow is substantially perpendicular to substrate.

16. according to the method for claim 6, wherein adjust the equal uniform flow that position that quantity of solvent in the casing environment further is included in substrate end in the casing forms pilot-gas, this equal uniform flow is substantially perpendicular to substrate.

17. according to the method for claim 13, wherein adjust the equal uniform flow that position that quantity of solvent in the casing environment further is included in substrate end in the casing forms pilot-gas, this equal uniform flow is substantially perpendicular to substrate.

18. according to the process of claim 1 wherein that adjusting pilot-gas to the solvent vapo(u)r that contains reaches capacity.

19., wherein adjust pilot-gas to the solvent vapo(u)r that contains and reach capacity according to the method for claim 2.

20., wherein adjust pilot-gas to the solvent vapo(u)r that contains and reach capacity according to the method for claim 6.

21., wherein adjust pilot-gas to the solvent vapo(u)r that contains and reach capacity according to the method for claim 13.

22. adjust the temperature that quantity of solvent in the casing environment further comprises the controlling liquid solvent according to the process of claim 1 wherein.

23., wherein adjust the temperature that quantity of solvent in the casing environment further comprises the controlling liquid solvent according to the method for claim 2.

24., wherein adjust the temperature that quantity of solvent in the casing environment further comprises the controlling liquid solvent according to the method for claim 6.

25., wherein adjust the temperature that quantity of solvent in the casing environment further comprises the controlling liquid solvent according to the method for claim 13.

26. according to the process of claim 1 wherein that the quantity of solvent of adjusting in the casing environment further comprises the gaseous tension of controlling in the solvent tank.

27. according to the method for claim 2, the quantity of solvent of wherein adjusting in the casing environment further comprises the gaseous tension of controlling in the solvent tank.

28. according to the method for claim 6, the quantity of solvent of wherein adjusting in the casing environment further comprises the gaseous tension of controlling in the solvent tank.

29. according to the method for claim 13, the quantity of solvent of wherein adjusting in the casing environment further comprises the gaseous tension of controlling in the solvent tank.

30. according to the process of claim 1 wherein that adjusting pilot-gas to the solvent vapo(u)r that contains does not reach capacity.

31., wherein adjust pilot-gas to the solvent vapo(u)r that contains and do not reach unsaturated according to the method for claim 2.

32., wherein adjust pilot-gas to the solvent vapo(u)r that contains and do not reach capacity according to the method for claim 6.

33., wherein adjust pilot-gas to the solvent vapo(u)r that contains and do not reach capacity according to the method for claim 13.

34., wherein the degree of saturation of pilot-gas is controlled by the temperature that changes pilot-gas according to the method for claim 30.

35., wherein change the pressure of pilot-gas and the degree of saturation of pilot-gas controlled according to the method for claim 30.

36. according to the process of claim 1 wherein that the evaporation of control solvent from polymer solution further comprises the solvent strength flux the control casing.

37., wherein control solvent and further comprise solvent strength flux the control casing from the evaporation of polymer solution according to the method for claim 2.

38., wherein control solvent and further comprise solvent strength flux the control casing from the evaporation of polymer solution according to the method for claim 6.

39., wherein control solvent and further comprise solvent strength flux the control casing from the evaporation of polymer solution according to the method for claim 13.

40., wherein control solvent strength flux in the casing by changing temperature in the casing according to the method for claim 36.

41., wherein control solvent strength flux in the casing by changing pressure in the casing according to the method for claim 36.

42., wherein control solvent strength flux in the casing by changing solvent speed in the casing according to the method for claim 36.

43. according to the method for claim 36, wherein change solvent strength flux in the casing and comprise and change the speed of uniform airflow basically, described air-flow produces in that wafer is terminal.

44., wherein control solvent strength flux in the casing by changing solvent speed in the casing according to the method for claim 41.

45. according to the method for claim 41, wherein by change wafer end in the casing basically uniform airflow control solvent strength flux in the casing.

46. according to the method for claim 45, wherein uniform airflow produces from the shower nozzle that comprises at least one spray orifice basically.

47. according to the method for claim 45, wherein uniform airflow produces from the shower nozzle that comprises a plurality of spray orifices basically.

48. according to the method for claim 47, the distance of wherein separating shower nozzle and substrate is greater than separating the then distance of the spray nozzle of taro of river.

49. according to the method for claim 47, the distance of wherein separating shower nozzle and substrate is than at least 5 times greatly of the distances of separating spray nozzle in proper order.

50., wherein said substrate rotation a period of time, be enough on substrate, provide film uniformity coefficient during this period of time less than 0.05% according to the method for claim 12.

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