CN101414551B

CN101414551B - Reduction of etch-rate drift in hdp processes

Info

Publication number: CN101414551B
Application number: CN2008102156432A
Authority: CN
Inventors: 王安川; 李永S; 麦诺基·韦列卡; 贾森·托马斯·布洛金; 权今和; 赫门特·P·芒吉卡
Original assignee: Applied Materials Inc
Current assignee: Applied Materials Inc
Priority date: 2007-09-07
Filing date: 2008-09-08
Publication date: 2011-09-14
Anticipated expiration: 2028-09-08
Also published as: CN101388341B; CN101414551A; CN101388341A

Abstract

The invention relates to reduction of etching speed deflection in a high-density plasma process. A processing chamber is seasoned by providing a flow of season precursors to the processing chamber. A high-density plasma is formed from the season precursors by applying at least 7500 W of source power distributed with greater than 70% of the source power at a top of the processing chamber. A season layer having a thickness of at least 5000 AA is deposited at one point using the high-density plasma. Each of multiple substrates is transferred sequentially into the processing chamber to perform a process that includes etching. The processing chamber is cleaned between sequential transfers of the substrates.

Description

Etch rate excursion reduces in the high-density plasma technology

The friendship justice of related application is quoted

The application is the U.S. Patent application No.60/970 that people such as Anchuan Wang submitted on September 7th, 2007,884 non-temporary patent application, denomination of invention is " INTEGRATED PROCESSMODULATION ", and the priority of the applying date of this U.S. Patent application is enjoyed in requirement.Be incorporated herein its full content as a reference.

The application also relates to submit to simultaneously, the common U.S. Patent application No.12/204 that transfer the possession of of people such as Anchuan Wang, 523, denomination of invention is " IMPURITY CONTROL IN HDP-CVDDEP/ETCH/DEP PROCESS ", and relates to " the GAPFILL EXTENSION OF HDP-CVD INTEGRATED PROCESSMODULATION SIO that people such as Anchuan Wang submitted on June 4th, 2007 ₂PROCESS ", the full content of each that is incorporated herein both is as a reference.

Technical field

The present invention relates to high-density plasma technology.

Background technology

One of persistence challenge that faces in semiconductor technology evolves is to increase the density and the interconnection of circuit element on substrate, and can not introduce parasitic interact (spuriousinteractions) between circuit element.Typically, prevent unnecessary interaction by providing employing gap that electrical insulating material is filled and groove so that element physically and on the electricity is isolated.Along with current densities increases, yet the width in these gaps reduces, and this has increased the aperture ratio in gap, and makes and fill the gap and do not stay cavity difficulty more.Form the cavity in the gap during not by complete filling and do not expect,, and the operation of completed device is had a negative impact because they can be such as by being captured in the impurity in the insulating material.

Filling the ordinary skill that adopts in the application in this gap is chemical vapour deposition (CVD) (" CVD ") technology.Conventional hot CVD technology provides reacting gas to substrate surface, heat-induced chemical reactions takes place on this substrate surface generate required film.Plasma enhanced CVD (" PECVD ") technology is impelled exciting and/or dissociating of reacting gas by apply radio frequency (" RF ") energy to the reaction zone near substrate surface, thereby produces plasma.The high response of the species in the plasma reduces the required energy of generation chemical reaction, thereby compares with the hot CVD technology of routine, reduces the required temperature of this CVD technology.Utilize high-density plasma (" HDP ") CVD technology can further bring into play these advantages, wherein fine and close plasma forms under low vacuum pressure, so plasma species even have more reactivity.Though each all broadly falls within these technology in " the CVD technology " of general designation, each in them all has makes them be fit to or not too be fit to the feature of some application-specific more.

The HDP-CVD system forms plasma, this plasma than the density of standard, capacitance coupling plasma CVD system greatly at least about 2 orders of magnitude.The example of HDP-CVD system comprises inductively coupled plasma system and electron cyclotron resonace (ECR) plasma system, and other system.The HDP-CVD system generally operates under the pressure lower than low-density plasma system.The low chamber pressure that uses in the HDP-CVD system provides the activation species (activespecies) of the angle distribution that has long mean free path and reduce.These factors, together with plasma density, help that sizable composition from plasma arrives separated gap closely even the deepest part, and compare, the film with improved clearance filling capability is provided with the film that in the low-density plasma CVD system, is deposited.

It is to impel by high-density plasma sputter deposited film simultaneously that the film that allows to utilize the HDP-CVD technology to be deposited has another factor of filling feature in improved gap.The sputter composition of HDP depositing operation slows down such as the deposition on some feature pattern at the turning of convex surfaces, thereby causes the increase of the clearance filling capability of HDP deposited film.Some HDP-CVDF systems introduce argon or similar heavy inert gas, with further promotion sputter effect.These HDP-CVD systems typically utilize the electrode in the substrate supports pedestal, thereby this electrode can form electric field towards substrate biasing plasma.In whole HDP depositing operation, can apply electric field, with further promotion sputter and be that known membrane provides better gap to fill feature.

Begin to think owing to deposition/sputter simultaneously, so HDP-CVD can fill gap or the groove that almost produces in any application.Yet semiconductor manufacturer has been found that there is physical constraints in the aperture ratio in the gap that can fill HDP-CVD technology.For example, the common HDP-CVD technology of cvd silicon oxide gap filling film that is used for is by comprising silane SiH ₄, oxygen molecule O ₂Form plasma with the process gas of argon Ar.Reported that the sputter that is caused by the argon in the process gas can hinder the gap filling effect when this technology is used to fill some high apertures of narrow-width ratio gap.Particularly, reported by on the material of the institute of the argon in technology sputter the top with the sidewall that is deposited on the gap of filling than bottom faster rate again at the sidewall in the gap of filling.Conversely, if the upper area of regrowth engages before the gap is by complete filling, then can cause in the gap, forming the cavity.

Fig. 1 is given in the constructed profile of the different phase silicon oxide film of deposition, fills restriction with relevant possible gap in the explanation number of C VD technology.With the form of amplifying a little the gap is shown and fills problem so that this problem to be described better.The top of Fig. 1 illustrates initial configuration 104, and its intermediate gap 120 is limited by two the adjacent feature patterns 124 and 128 with horizontal surface 122, and the horizontal surface in the bottom, gap that is denoted as 132.As shown in structure 108, that is, from the few top second portion, conventional HDP-CVD silica depositing operation causes the direct deposition on the horizontal surface 132 of 120 bottoms, gap and on the horizontal surface above characteristic pattern 124 and 128 122 among the figure.Yet, because the recombinant of the material that sputters from silicon oxide film along with silicon oxide film growth also causes the indirect deposition (being called as " deposition again ") on the sidewall 140 in gap 120.Than in using, the continuous growth of silicon oxide film causes the formation thing 136 on the top of sidewall 140 in some little width, high aperture, and this forms thing 136 to surpass the growth rate court each other growth of film in the lower sidewall cross growth.This trend has been shown, and the final result in structure 116 is to form cavity 144 in film in structure 108 and 112.It is very directly related with the speed and the feature that deposit to form the possibility in cavity again.

Therefore, still exist in this area improving the general needs of gap filling technique.

Summary of the invention

Embodiments of the present invention are provided at the method for deposited film on a plurality of substrates.In first group of execution mode, treatment chamber is carried out Ageing Treatment by timeliness predecessor (season precursor) air-flow is provided to treatment chamber.By applying the source power of 7500W at least, form high-density plasma by the timeliness predecessor, wherein be furnished with source power greater than 70% in the top portion of treatment chamber.Utilize high density plasma deposition to have at least 5000 at a some place The timeliness layer of thickness.Each substrate that order transmits in a plurality of substrates in treatment chamber comprises etched technology to carry out on each substrate in a plurality of substrates.Clean chamber between each substrate that transmits in proper order in a plurality of substrates.

In different execution modes, at least 5000 Thickness can comprise at least 7500 Thickness or can comprise at least 10,000 Thickness.Timeliness predecessor air-flow can be provided as, such as SiH ₄Siliceous air-flow and such as O ₂Oxygen flow.The flow rate of oxygen-containing gas can perhaps can be below 0.8 times of flow rate of silicon-containing gas less than the flow rate of silicon-containing gas.In some instances, add the gas flow that does not react with silicon-containing gas and oxygen-containing gas is provided, have flow rate sometimes less than 200sccm.

In second group of execution mode, treatment chamber is carried out Ageing Treatment, and each substrate that order transmits in a plurality of substrates in treatment chamber comprises etched technology to carry out on each substrate in a plurality of substrates.Part cleaning by carrying out treatment chamber, heat treated chamber and finish the cleaning of treatment chamber then then, and transmit clean chamber between each substrate in a plurality of substrates in order.

The cleaning of carrying out the part cleaning of treatment chamber and finishing treatment chamber respectively comprises to treatment chamber and flows into the halogen predecessor and form high-density plasma by this halogen predecessor.An example of suitable halogen predecessor is F ₂Can carry out 75% the part cleaning that surpasses cleaning terminal point (endpoint ofthe clean).Can come the heat treated chamber by flowing into heated air to treatment chamber and forming high-density plasma by heated air.The example of heated air comprises O ₂, Ar and He etc.Can form high-density plasma by being applied to the source power that approximately equal is distributed between source, top and the side source.

Can realize further understanding by the remainder of reference specification and accompanying drawing to characteristics of the present invention and advantage.

Description of drawings

Fig. 1 provides the constructed profile of explanation formation in cavity during the space stuffing techniques of prior art;

Fig. 2 is the simplification profile of the integrated circuit that comprises that the part of a plurality of fleet plough groove isolation structures is finished;

Fig. 3 A and 3B distribute the schematic diagram that feature is filled in structure split shed gap regional and the dense accumulation zone is shown;

Fig. 4 A summarizes the flow chart that is used for deposited film on substrate in embodiments of the present invention;

Fig. 4 B is the flow chart of the particular deposition technology that can use with the method for Fig. 4 A of general introduction, and deposition step and etching step alternately occur in this particular deposition technology;

Fig. 4 C be general introduction can adopt in some embodiments as the part of the method for Fig. 4 A treatment chamber is carried out the flow chart of the method for Ageing Treatment;

Fig. 4 D is the flow chart as the method for the clean chamber of the part of the method for Fig. 4 A that general introduction can be adopted in some embodiments;

Fig. 5 A is the reduced graph of an execution mode that can implement the high density plasma CVD system of method of the present invention;

Fig. 5 B is the simplification profile of the compression ring that can use in conjunction with the exemplary process system of Fig. 5 A.

Embodiment

Embodiments of the present invention relate to the method for deposited film on substrate that merges etching step.In particular exemplary of the present invention is used, provide and utilize high-density plasma CVD process deposits silicon oxide layer to fill the method in the gap in the substrate surface.Have excellent clearance filling capability according to the silicon oxide film that technology of the present invention deposited, and can fill, for example, the gap that shallow trench isolation occurs in (" STI ") structure.Thereby be adapted at making in the multiple integrated circuit by the film that method of the present invention deposited and use, be included in those integrated circuits that have less than the characteristic size of the 45nm order of magnitude and use.

Inventor's a discovery as their part to this deposition process research, is to exist along with the processing substrate is many more system's trend that etch-rate is more little during the etching part of this method.Even when the process conditions of each substrate are basic identical, " etch-rate drift (etch-rate drift) " also takes place.

Fig. 2 illustrates the structure type that can fill according to the embodiment of the present invention, and Fig. 2 provides the simplification profile of the integrated circuit of finishing the part 200.Form this integrated circuit on the substrate 204 that comprises a plurality of sti structures, wherein each sti structure normally approaches pad oxide layer 220 by forming on the surface of substrate 204, what formation silicon nitride layer 216 formed on pad oxide layer 220 then.Then, utilize standard photolithography techniques, and be passed in the nitride/oxide stack etched trench 224 in the substrate 204 nitration case and oxide layer composition.Fig. 2 illustrates integrated circuit, and this integrated circuit can comprise the zone 208 of the relative dense accumulation with transistor or other active devices, and can comprise the open area 212 of relative isolation.Active device in open area 212 can pass through big more separated from one another more than the separation of an order of magnitude than the separation (separation) in the zone 208 of dense accumulation, but thinks that " open area " is at least five times the zone of the width of its intermediate gap for the gap width in " close quarters " as used in this.

Embodiments of the present invention provide utilizes the depositing operation with better gap filling property to use the method for coming filling groove 224 such as the electrical insulating material of silicon dioxide.In some instances, before space stuffing techniques, the initial laying of deposition produces (" ISSG ") or other thermal oxide layers as situ steam on substrate, perhaps can be silicon nitride layer.An advantage of this liner of deposition provides suitable fillet before filling groove 224, and this can help avoid the described influence of early stage gate breakdown in formed transistor.

As used in this, high-density plasma technology is plasma CVD technology, comprise deposition and sputter composition simultaneously, and application has with 10 ¹¹Ions/cm ³Or the plasma of the ion concentration of the bigger order of magnitude.The relative rank of the combined deposition of high-density plasma and sputter feature can depend on some factors, as is used to provide the flow rate of admixture of gas, in order to keep the source power rank that plasma applies, imposes on the bias power of substrate etc.The combination of these factors can quantize easily with " deposition/sputter ratio ", is expressed as D/S sometimes to define the feature of this technology:

This deposition/sputter ratio is along with deposition increases and increases, and along with sputter increases and reduces.Employed in the definition as D/S, " net deposition rate " refers to the deposition rate that records when taking place simultaneously when deposition and sputter." pattern-free sputter rate (blanket sputtering rate) " is the sputter rate that records when carrying out technical recipe under the condition of no deposition gases; Pressure in the treatment chamber is adjusted to the pressure between depositional stage, and sputter rate records on the pattern-free thermal oxide.

As known to persons skilled in the art, other equivalent measurements can be used to quantize the relative deposition and the sputter contribution (contribution) of HDP technology.Optional ratio commonly used is " etching/deposition ratio ",

Should " etching/deposition ratio " along with sputter increases and increases and along with the deposition increase and reduce.As what use in the definition of E/D, " net deposition rate " refers to the deposition rate that records when taking place simultaneously when deposition and sputter once more.Yet " only source deposition rate (source-only deposition rate) " refers to the deposition rate that recording when technical recipe is not having to carry out under the situation of sputter.With term D/S ratio embodiments of the present invention are described at this.Though D/S and E/D are not accurate inverses, they are inverse correlation (inverselyrelated), and it should be appreciated by those skilled in the art that the conversion between them.

Generally by comprising the precursor gas air-flow that can also play the sputter agent, and the flowing gas air-flow that plays the sputter agent in some instances, required D/S ratio obtained for the known steps in the HDP-CVD technology.The element reaction that is comprised by precursor gas is to form the film with required composition.For example, for the cvd silicon oxide film, precursor gas can comprise such as silane SiH ₄Silicon-containing gas, and such as oxygen molecule O ₂The reacted thing.By comprising that the precursor gas with required dopant can add dopant to film, such as by comprising SiF ₄Air-flow comprises PH so that film is fluoridized ₃Air-flow so that the film phosphatization comprises B ₂H ₆Air-flow so that the film boronation comprises N ₂Air-flow so that film nitrogenize etc.Flowing gas can with H ₂Air-flow or comprise the inert gas of He air-flow, perhaps such as Ne, Ar or Xe's in addition heavier inert gas provide together.The sputter rank that provides by different flowing gas directly and their atomic mass (or at H ₂Situation in molecular mass) relevant, utilize H ₂Produce even than He sputter still less.Embodiments of the present invention provide usually has the flowing gas air-flow of average molecular mass less than 5amu.This can be by utilizing single low quality gas, such as pure H basically ₂Air-flow or basically the air-flow of pure He obtain.Alternatively, sometimes, air-flow can be provided by multiple gases, such as by H both is provided ₂Air-flow provides the He air-flow again, and they mix in the HDP-CVD treatment chamber.Alternatively, thus gas can be pre-mixed H sometimes ₂The air-flow of/He offers treatment chamber with mixed state.Independent better quality gas flow can also be provided, perhaps comprise better quality gas in being pre-mixed thing, the relative flow rate and/or the concentration that are pre-mixed thing simultaneously are chosen as the average molecular mass of keeping less than 5amu.

High aperture than structure in, generally speaking, have been found that the low quality flowing gas that adopts relative high flow rate, improve clearance filling capability to compare with the flowing gas of more traditional employing such as Ar.This is considered to by utilizing He or H ₂The result that the deposition again that realizes as flowing gas reduces.Even but adopt this low quality flowing gas, between depositional stage, also there is the risk of turning flanging (comer clipping).Be appreciated that this influence with reference to Fig. 3 A and 3B, Fig. 3 A and 3B illustrate respectively for the gap in the dense accumulation zone with for the gap in the open area, the influence of the sputter composition (component) of HDP technology.

Specifically, the gap 304 among Fig. 3 A is high aperture ratio gaps, has the material that utilizes HDP-CVD technology to be deposited, this material (cust) structure 308 that tapers off to a point on horizontal surface.When material 312 response during along the collision of the plasma ion of route 316 and from most advanced and sophisticated 308 sputters, deposition again takes place.The material 312 of institute's sputter is along route 320, arrives the sidewall 324 on the opposite side in gap 304.This influence is symmetrical, and therefore when material must be arrived the right side away from the left side in gap by sputter, material also must be arrived the left side away from the right side in gap by sputter.The protection of the deposition again of material can excessive sputter and cause the turning flanging.

In the open area, in the open area 330 as shown in Fig. 3 B, there is not this symmetry.In this example, deposition causes similar most advanced and sophisticated 308 ' formation, but when material 312 ' response along the collision of the plasma ion of route 316 ' and along route 320 ' during by sputter, the opposite side in gap too far can not have the deposition again of protectiveness.The sputter as the turning identical materials of the structure among Fig. 3 A is stood at the turning of the structure among Fig. 3 B, but does not have the compensation effect of reception from the material of the opposite side institute sputter in gap.Therefore, there is flanging turning and the damage risk of the increase of square structure down.

The flow chart of Fig. 4 A has been summarized method of the present invention, and Fig. 4 A provides the general introduction of described method.These methods are applied to the operation of several substrates in the common process chamber, wherein carry out a plurality of technologies on each substrate.At block 402, method begins, and treatment chamber is carried out Ageing Treatment,, utilizes the internal structure of coated materials treatment chamber that is, and an example of this material comprises SiO ₂At block 404, substrate is sent in the treatment chamber, thereby carries out technology at block 406 on that substrate.Even when the overall result of the application of technology was the clean deposition of material, this technology comprised effective etching (significant etching).At block 410, substrate is transmitted out treatment chamber, in block 412 these treatment chamber of cleaning.

Implement to check at block 414 whether the entire substrate operation is finished.Typical substrate-operations may comprise five substrates, can also use the substrate of more or less quantity in the specific execution mode of difference.If substrate-operations is not finished, then in treatment chamber, transmit next substrate in this operation, and this next substrate repeated this method at block 404.In case all substrate-operations are finished, utilize at the same process of block 406 or utilize different process this treatment chamber of Ageing Treatment once more at block 402 so, so that be another substrate-operations preparation.

Fig. 4 B is given in the detailed content of those technologies that block 406 can adopt.In this example, utilize deposition/etching/depositing operation on substrate, to obtain to deposit, and more generally, the technology of other types of (significant etching component) that method of the present invention can be applied to have effective etching composition.Substrate is typically such as the semiconductor wafer of 200mm or 300mm diameter.

At block 420, the precursor gas air-flow provides to chamber, and the precursor gas air-flow comprises silicon predecessor air-flow, oxygen predecessor air-flow and flowing gas air-flow.Table 1 provides and has been used to use single silane SiH ₄, oxygen molecule O ₂And H ₂The exemplary flow rate of the unadulterated silicate glass of flow deposition (" USG "), but should be appreciated that and also can use other precursor gas and other flowing gas that comprises dopant source as previously mentioned.

Table I: the exemplary flow rate that is used for the USG deposition

It is as shown in the table, and for the wafer of 200-mm and 300-mm diameter, the flow rate of precursor gas is similar, but the flow rate of flowing gas is generally higher.

In block 422,, form the plasma of high concentration by gaseous air-flow (gaseous flow) by energy is coupled into chamber.The current techique that is used to produce the high concentration plasma is the inductance coupling high radio-frequency (RF) energy.The D/S ratio is not only definite by the flow rate of gas, but also is determined by the power density that is coupled into chamber, is determined by the intensity of the biasing that can be applied to substrate, is determined by the temperature in the chamber, and it is definite to stop up interior pressure by the chamber, and is determined by other factors.For the deposition of the initial part of film in block 424, in certain embodiments, can select this processing parameter to surpass 20 D/S ratio, and 900-6000 is provided simultaneously to provide

The low relatively deposition rate of (dust/minute).The inventor has been found that for very little characteristic size this combination of general using low deposition rate and high D/S ratio improves the gap and fills feature.

After deposition is finished, in block 426, finish deposition precursor thing air-flow, check at block 428 whether film has reached required thickness then.Embodiments of the present invention comprise by separated two depositional phases of etch phase at least, can have 5-15 depositional phase or even more depositional phase continually according to the concrete feature in the gap of filling.

At block 430, by flowing into the etch phase that the halogen predecessor begins technology, the halogen predecessor generally includes such as NF ₃Or the fluorine predecessor of chlorofluorocarbon.At block 432, utilize high source power density to form the high concentration plasma by the halogen predecessor.In some embodiments, source power density is about 80,000 and 140,000W/m ²Between, this is equivalent to total source power between about 6000 and 10,000 watts for 300-mm diameter wafer, and is equivalent to total source power between about 2500 and 4500 watts for 200-mm diameter wafer.The inventor has been found that and uses high source power to make sedimentary section (deposition profile) than using low source power symmetry more.In some embodiments, total source power is distributed in top and the side source, thereby the major part of source power is provided by the side source.For example, the side source power can be 1-5 a times of top source power, and in a specific implementations, the side source power is 3 times of top source power.

In block 434, use the film of the halogen plasma of generation with etch-back (etch back) deposition.Though material can etched concrete amount depends on the concrete structure of substrat structure relatively, usually in the etching cycle of back material can etched amount greater than the etched amount of material in the etching cycle in front.This is the General Result of the fact that changes owing to deposition and the order of etching step of the whole layout of substrate.The general trend of the order of this step is that the etch phase layout in the cycle becomes and trends towards the big more amount of etching more.At block 436, finish halogen forerunner logistics, in block 420, by flowing into the air-flow of silicon predecessor, oxygen predecessor and flowing gas once more, thereby technology can turn back to the depositional phase.

Usually will use identical predecessor for the deposition of material during being desirably in each depositional phase, and will use identical predecessor for removing material in etch phase, still for the present invention this not necessarily.Material in amount that each depositional phase deposited usually 300 to 1000

Between, whole arts demand cycle still less when each is used bigger deposition in cycle simultaneously.In order to deposit the material of same amount, when each cycle deposition 300

The time, need be in each cycle deposition 1000

The cycle that Shi Dayue is six times.

Fig. 4 C illustrates in certain embodiments at block 402 operable aging treatment process.At block 440, aging treatment process begins, in the built-in condition of imitating of chamber immediately.In some embodiments, this condition is included in the chamber pressure between 25 and 65 millitorrs (mtorr).Provide timeliness predecessor air-flow at block 442, comprise SiO in Ageing Treatment ₂In the execution mode of coating, predecessor can comprise such as the silicon-containing gas of silane and oxygen-containing gas.For example, the silicon predecessor can comprise SiH ₄And the oxygen predecessor can comprise O ₂In some embodiments, the flow rate of oxygen-containing gas is less than the flow rate of silicon-containing gas, it can be below 0.9 times of flow rate of silicon-containing gas, it can be below 0.8 times of flow rate of silicon-containing gas, it can be below 0.7 times of flow rate of silicon-containing gas, can be below 0.6 times of flow rate of silicon-containing gas, perhaps can be below 0.5 times of flow rate of silicon-containing gas.For example, using SiH ₄And O ₂An execution mode in, O ₂Flow rate be 300sccm and SiH ₄Flow rate be 470sccm, flow-rate ratio approximates 0.65 greatly.The air-flow that provides at block 442 can also comprise the gas that does not react sometimes, such as the execution mode that uses He, Ne or Ar.The flow rate of the described gas that does not react typically less than 200sccm reducing splash effect, and can be 0sccm.

At block 444, form high-density plasma by coupling energy in treatment chamber by the timeliness predecessor as mentioned above.The preferably preferential and top source power of energy apply coupling, and in an embodiment of the present invention, energy has the source power that the top applied at chamber more than 70%, in the source power that the top applied of chamber more than 80%, at more than 90% of the source power that the top applied of chamber, perhaps even in 100% of the source power that the top applied of chamber.The exemplary power that is applied in one embodiment, is utilized at the top of treatment chamber whole about 9000W power that apply greater than 7500W.

At block 446, this high-density plasma is used to deposit the Ageing Treatment layer.Though expect that usually the thickness of Ageing Treatment layer can be uneven, in some embodiments, it has at least 5000 at a some place

Thickness, have at least 6000 at a some place

Thickness, have at least 7500 at a some place Thickness, have at least 10,000 at a some place

Thickness, perhaps have at least 12,500 at a some place Thickness.After Ageing Treatment layer deposition, at block 448, suspension of prescription predecessor air-flow.

Fig. 4 D has provided according to the embodiment of the present invention the flow chart in a method of block 412 cleaning chambers of Fig. 4 A.This clean method comprises two step cleanings, and carries out heating process between two steps of cleaning.

Therefore, at block 460, after substrate is finished processing, flowed into treatment chamber such as the halogen predecessor of F2.At block 462, high-density plasma is formed by the halogen predecessor, and at block 464, utilizes high-density plasma to carry out local cleaning.Can carry out part cleaning in some embodiments greater than 75% process endpoint.

After having finished first cleaning, stop halogen forerunner logistics at block 466.At block 468, this air-flow substitutes with heating air flow, is wherein formed by this heated air at block 470 heating plasmas.Only as an example, in different execution modes, heated air can comprise O2, Ar and/or He, and 12, the exemplary source power of 000W is applied in equal top and sidepiece distribution and continues 30 to 120 seconds time.Heated the effect of the general cooling of offsetting the chamber that during cleaning, takes place in the middle of this.

After block 472 stops heating air flow, can adopt halogen predecessor air-flow once more at block 474, and form high-density plasma once more at block 475, be used to finish chamber clean.

The illustrative substrate treatment system

The inventor has used the Clara by Santa, the APPLIED MATERIALS of California (Santa Clara city), the ULTIMA that INC. (Applied Materials Inc) makes ^TMThe system implementation embodiments of the present invention, the general description of said system is provided at the United States Patent (USP) U.S.No.6 of common transfer, 170, in 428, this patent application is by Fred C.Redeker, Farhad Moghadam, HirogiHanawa, Tetsuya Ishikawa, Dan Maydan, Shijian Li, Brian Lue, Robert Steger, Yaxin Wang, Manus Wong and Ashok Sinha submitted to July 15 in 1996, and its denomination of invention is: " SYMMETRIC TUNABLE INDUCTIVELY COUPLED HDP-CVDREACTOR ", here, all disclose it as a reference incorporated.The general introduction of this system is provided below in conjunction with Fig. 5 A and 5B.Fig. 5 A is exemplary to show the structure of this in one embodiment HDP-CVD system 510.System 510 comprises chamber 513, vacuum system 570, source plasma system 580A, biasing plasma system 580B, gas delivery system 533 and remote plasma clean system 550.

The top of chamber 513 comprises the vault of making by such as the ceramic dielectric material of the nitride of the oxide of aluminium or aluminium 514.Vault 514 defines the coboundary in plasma treatment zone 516.Plasma treatment zone 516 is to be the boundary with the upper surface of substrate 517 and substrate support 518 in the bottom.

Heating plate 523 and coldplate 524 on vault 514 and with vault 514 hot links.Heating plate 523 and coldplate 524 allows dome temperature is controlled on about 100 ℃ to 200 ℃ scope in approximately ± 10 ℃.This allows at various process optimization dome temperatures.For example, wish that dome temperature keeps the temperature higher than depositing operation for cleaning or etch process.The accurate control of dome temperature also reduces to peel off in the chamber or grain amount and improve adhesion between sedimentary deposit and the substrate.

The lower part of chamber 513 comprises the main component 522 that chamber is connected to vacuum system.The base part 521 of substrate support 518 is installed on the main component 522 and with main component 522 and forms continuous inner surface.Substrate by robot supporting plate (not shown) by the insertion in the sidewall of chamber 513/shift out the opening (not shown) to be transmitted into chamber 513 and to pass out chamber 513.The lifter pin (not shown) raises under the control of motor (also not going out) and reduces then, handle down position 556 so that substrate is moved to from the robot supporting plate in last installation site 557, handling down on the substrate receiving unit 519 that the position substrate is placed on substrate support 518.Substrate receiving unit 519 comprises electrostatic chuck 520, and this electrostatic chuck 520 is being fixed to substrate on the substrate support 518 during the substrate processing.In preferred embodiment, substrate support 518 is made by the oxide of aluminium or the ceramic material of aluminium.

Vacuum system 570 comprises choke valve main body (throttle body) 525, and this throttle valve body 525 holds twayblade choke valve (twin-blade throttle valve) 526 and is attached to sluice valve 527 and turbomolecular pump 528.Should be noted that choke valve main body 525 provides the minimum obstruction to air-flow, and allow symmetry to bleed.Sluice valve 527 can allow to make pump 528 and choke valve main body 525 to isolate, and can come the control chamber chamber pressure by the exhaust capacity of restriction when choke valve 526 is opened fully.The pressure that the layout of choke valve, sluice valve and turbomolecular pump allows accurately and stably to control chamber up to about 1 millitorr to about 2 millitorrs.

Source plasma system 580A comprises top coil 529 and the lateral coil 530 that is installed on the vault 514.The earth shield (not shown) of symmetry reduces the electric coupling between the coil.Top coil 529 is by top source radio frequency (SRF) generator 531A power supply, and lateral coil 530 is powered by side SRF generator 531B, and allows independently power rank and operating frequency for each coil.This dual coil system allows the radiation ion concentration in the control chamber 513, thereby improves the uniformity of plasma.Lateral coil 530 and top coil 529 normally drive (inductively driven) in inductive ground, and this does not need auxiliary electrode.In embodiment, top source radio freqnency generator 531A is provided at the radio-frequency power up to 2,500 watts under the nominal 2MH, and side source radio freqnency generator 531B is provided at the radio-frequency power up to 5,000 watts under the nominal 2MH.The operating frequency of top radio freqnency generator and side radio freqnency generator can depart from nominal operation step (for example, respectively to 1.7-1.9MHz and 1.9-2.0MHz) to improve the plasma luminous efficiency.

Biasing plasma system 580B comprises biasing radio frequency (" BRF ") generator 531C and bias match network 532C.Biasing plasma system 580B capacitive coupling substrate part 517 is to main component 522, and it plays the effect of auxiliary electrode.This biasing plasma system 580B is used to improve the transmission to substrate surface of the plasma species (for example ion) that caused by source plasma system 580A.In embodiment, as discussed below, the biasing plasma generator is provided at less than the RF power up to 10,000 watts under the frequency of 5MHz.

RF generator

531A and 531B comprise numerically controlled synthesizer, and work on the frequency range between about 1.8 to about 2.1MHz.As one of ordinary skill in the understanding, each generator comprises RF control circuit (not shown), and this RF control circuit is measured the power from substrate and coil back generator, and regulates operating frequency to obtain minimum reflection power.The RF generator is typically designed to having under 50 ohm the load of characteristic impedance and works.RF power can be reflected by the load that has with the impedance of generator different characteristic.This can reduce the power that transfers to load.In addition, the power by load reflected back generator can make generator cross load and damage generator.Because the impedance of plasma according to the concentration of plasma and other factors from less than 5 ohm in greater than 900 ohm scope; and because the power of reflection can be the function of power, so increase function and the protection generator that is passed to plasma from the RF generator according to the frequency of the power adjustments generator that reflects.The another kind of method that reduces reflection power and raise the efficiency is to adopt matching network.

Matching network

532A and 532B make the output impedance of

generator

531A and 531B and they separately

coil

529 and 530 be complementary.The RF control circuit can come tuning two matching networks by the value that changes the capacitor in the matching network when load changes, so that generator and load are complementary.The RF control circuit can tuning matching network when the power from load reflected back generator surpasses certain limitation.Constant match is provided and forbids that effectively a kind of method of the tuning matching network of RF control circuit is the reflection power restriction that the random desired value that surpasses reflection power is set.This can matching network is constant under the nearest condition of plasma helps stable plasma under some conditions by keeping.

Other measurement can also help stable plasma.For example, the RF control circuit can be used in the power of determining to flow to load (plasma), and it is constant basically during sedimentary deposit with the power that keeps carrying to increase or reduce the generator power output.

Gas delivery system 533 provides the gas from several sources 534A-534E chamber to be used to handle substrate by gas delivery pipeline 538 (only showing wherein some) to chamber.Can understand actual source that is used for source 534A-534E and changing actual the connection to the feed-line 538 of chamber 513 according to deposition and the cleaning procedure in chamber, carried out as those of ordinary skills.Gas imports in the chamber 513 by compression ring (gasring) 537 and/or top nozzle 545.Fig. 5 B is simplification, the partial cross section figure of chamber 513 that shows the additional detail of compression ring 537.

In one embodiment, the first and

second gas source

534A and 534B and the first and second gas flow controller 535A ' and 535B ' provide gas by the ring air chamber (ring plenum) 536 of gas delivery pipeline 538 (only showing wherein some) in compression ring 537.Compression ring 537 has multiple source gas nozzle 539 (only showing one of them in order to illustrate), and multiple source gas nozzle 539 provides uniform gas flow on substrate.Nozzle length and nozzle angle can change to allow adjusting even distribution and gas utilization ratio at special process in independent chamber.In preferred embodiment, compression ring 537 has 12 source gas nozzles being made by the oxide ceramics of aluminium.

Compression ring 537 also has a plurality of oxidizer gas nozzles 540 (only showing one of them), in preferred embodiment, a plurality of oxidizer gas nozzles and source gas nozzle 539 coplines and shorter than source gas nozzle 539, and in one embodiment, a plurality of oxidizer gas nozzles accept the gas of autonomous agent air chamber (bodyplenum) 541.In some embodiments, need source gas and oxidant gas before injecting chamber 513, not to mix.In other embodiments, by between main body air chamber 541 and compression ring air chamber 536, providing hole (not shown) oxidant gas and source gas before injecting chamber 513, can mix.In one embodiment, the 3rd, the 4th and the

5th gas source

534C, 534D and 534D ' and the third and fourth

gas flow controller

535C and 535D ' provide gas by gas delivery pipeline 538 to the main body air chamber.Except valve, can cut off gas from flow controller to chamber such as 543B (other valve is not shown).In implementing some embodiments of the present invention, source 534A comprises silane SiH4 source, and source 534B comprises oxygen molecule O2 source, and source 534C comprises silane SiH4 source, and source 534D comprises helium He source, and source 534D ' comprises hydrogen molecule H2 source.

In the execution mode that uses inflammable, poisonous or corrosive gas, need after deposition, remove the gas of staying in the gas delivery pipeline.For example, this can use such as the 3 logical valves of 543B and finish, so that chamber 513 isolates with feed-line 538A, and feed-line 538A is communicated with utmost point pipeline 544 before the vacuum.Shown in Fig. 5 A, other similar valve such as 543A and 543C, can be combined on other gas delivery pipeline.This triple valve can be placed as far as possible near chamber 513 so that the volume minimum of the gas delivery pipeline that can not ventilate (between triple valve and chamber).In addition, two logical (on-off) valve (not shown) can be placed between mass flow controller (" MFC ") and the chamber or between gas source and MFC.

Referring again to Fig. 5 A, chamber 513 also has top nozzle 545 and top ventilating opening 546.Top nozzle 545 and top ventilating opening 546 allow the top air-flow and the sidewind of independent control gaseous, deposition and doping parameters that this improves film uniformity and allows to regulate subtly film.Top ventilating opening 546 is the annular opening around top nozzle 545.In one embodiment, the first gas source 534A provides source gas nozzle 539 and top nozzle 545.Nozzle MFC535A ' control in source is delivered to the amount of the gas of source gas nozzle 539, and nozzle MFC535A control in top is transported to the amount of the gas of top gas nozzle 545.Similarly, two of MFC535B and 535B ' can be used to control by such as the single source of oxygen of source 534B to the two Oxygen Flow of top ventilating opening 546 and oxidizer gas nozzles 540.In some embodiments, oxygen does not offer chamber from any side nozzle.Provide to the gas of top nozzle 545 and top ventilating opening 546 and can keep separating before flowing into chamber 513, perhaps described gas can mixing in top air chamber 548 before inflow chamber 513.The separation source of same gas can be used to provide the various parts of chamber.

Provide remote microwave generation plasma cleaning system 550 with deposition residues periodically from chamber part.These cleaning systems comprise that the purge gas source 534E (for example, unimolecule fluorine, nitrogen trioxide, other fluorocarbon or equivalent) from reactor cavity 533 produces the remote microwave generator 551 of plasma.Active specy (reactive species) by this plasma generation transfers to chamber 513 by applicator pipeline (applicator tube) 555 through clean air input port 554.Be used to hold the attack of the necessary anti-plasma of material (for example, cavity 553 and applicator pipeline 555) of cleaning plasma.Owing to the concentration of needed plasma species along with the distance from reactor cavity 553 reduces, so the distance between reactor cavity 553 and the input port 554 should keep short as far as possible.In long-range cavity, produce cleaning plasma and allow to use the efficient microwave generator, and can not make chamber part suffer the influence of temperature, radiation or the bombardment of the glow discharge of appearance in position in forming plasma.Therefore, Min Gan parts such as electrostatic chuck 520, do not need to cover desired catch in the in-situ plasma cleaning procedure (dummy wafer) or other protection relatively.In Fig. 5 A, plasma cleans system 550 is depicted as and is arranged on chamber 513 tops, but also can use other position.

Can provide baffler 561 will being inducted into chamber near the top nozzle, and guide the air-flow of the plasma of long-range generation by the air-flow of the source gas that provides in the nozzle of top.The source gas that is provided by top nozzle 545 is conducted through centre gangway and enters chamber, and the plasma species of the long-range generation that is provided by clean air input port 554 is directed to the side of chamber 513 by baffler 561.

Those skilled in the art will recognize that under the situation that does not break away from spirit of the present invention concrete parameter can change with different process conditions at different treatment chamber.Other modification also is obvious to those skilled in the art.These equivalents and modification are intended to comprise within the scope of the invention.Therefore scope of the present invention is not limited to above-mentioned execution mode, but is limited by appended claims.

Claims

1. the method for a deposited film on a plurality of substrates, this method comprises:

Treatment chamber is carried out Ageing Treatment;

Order transmits each substrate in described a plurality of substrate in described treatment chamber, to carry out the depositing operation that comprises at least one etch, substep on each substrate in described a plurality of substrates; And

The described treatment chamber of cleaning between each substrate that transmits in proper order in described a plurality of substrate, wherein the described treatment chamber of cleaning comprises between each substrate that transmits in proper order in described a plurality of substrate:

By forming high-density plasma, carry out the part cleaning of described treatment chamber by halogen forerunner logistics;

Then, stop described halogen forerunner logistics;

Then, be used to from the described treatment chamber of the heated by plasma of heated air; And

Then, by forming high-density plasma, finish the cleaning of described treatment chamber by halogen forerunner logistics.

2. method according to claim 1 is characterized in that, described halogen predecessor comprises F2.

3. method according to claim 1 is characterized in that, the part cleaning of carrying out described treatment chamber comprises the part cleaning of execution greater than the terminal point of 75% cleaning.

4. method according to claim 1 is characterized in that, heats described treatment chamber and comprises:

Form high-density plasma by described heated air.

5. method according to claim 4 is characterized in that, described heated air comprises and is selected from O ₂, Ar and He gas.

6. method according to claim 4 is characterized in that, forms high-density plasma by described heated air and comprises the source power that is applied to approximately equal distribution between top source and the sidepiece source.

7. method according to claim 1 is characterized in that, described treatment chamber is carried out Ageing Treatment comprise:

Provide timeliness predecessor air-flow to described treatment chamber;

By applying the source power of 7500W at least, and form high-density plasma, wherein be furnished with source power greater than 70% in the top portion of described treatment chamber by the timeliness predecessor; And

Utilize described high density plasma deposition to have at least 5000 at a some place

The timeliness layer of thickness.

8. method according to claim 7, wherein, described at least 5000

Thickness comprise at least 7500

Thickness.

9. method according to claim 7, wherein, described at least 5000

Thickness comprise at least 10,000

Thickness.

10. method according to claim 7 wherein, provides described timeliness predecessor air-flow to comprise to described treatment chamber:

Provide the silicon-containing gas air-flow to described treatment chamber; And

Provide the oxygen-containing gas air-flow to described treatment chamber.

11. method according to claim 10, wherein, the flow rate of described oxygen-containing gas is less than the flow rate of described silicon-containing gas.

12. method according to claim 10, wherein, the flow rate of described oxygen-containing gas is below 0.8 times of flow rate of described silicon-containing gas.

13. method according to claim 10, wherein, described silicon-containing gas comprises SiH ₄And described oxygen-containing gas comprises O ₂

14. method according to claim 10 wherein, provides timeliness predecessor air-flow also to comprise to described treatment chamber the gas flow that does not react with described silicon-containing gas and described oxygen-containing gas is provided.

15. method according to claim 14, wherein, the flow rate of the described gas that does not react with described silicon-containing gas and described oxygen-containing gas is the flow rate less than 200sccm.