CN221797656U - Vapor deposition equipment and upper liner thereof - Google Patents

Abstract

The utility model provides a vapor deposition device and an upper liner thereof, comprising a reaction cavity, wherein a tray is arranged below the reaction cavity, the upper surface of the tray is a wafer bearing surface, and the device comprises: an upper liner disposed within the reaction chamber opposite the wafer bearing surface, the upper liner and the wafer bearing surface forming a reaction region therebetween; a gas inlet means for injecting process gas laterally into the reaction zone; the upper liner is formed by rotating a second bus around the central shaft of the air inlet device, the second bus is formed by rotating a first bus around the starting point of the second bus by a set angle in the vertical direction, and the first bus is provided with a starting point close to the central shaft and an ending point far away from the central shaft; the points x and y are any two points on the first bus, the vertical distances between the points x and y and the wafer bearing surface are respectively recorded as h ₁、h₂, the horizontal distances between the points x and y and the central axis are respectively recorded as l ₁、l₂, the points x and y meet h ₁×l₁＝h₂×l₂, or the upper liner is formed by rotating a third bus around the central axis of the air inlet device, the third bus is a straight line, and the third bus and the first bus share a starting point and an end point.

Description

A vapor deposition device and upper liner thereof

Technical Field

The utility model relates to the field of semiconductor equipment, in particular to a vapor deposition device and an upper liner thereof.

Background Art

Chemical Vapor Deposition (CVD) refers to the process in which reactants react chemically on the wafer surface under gaseous conditions to form a thin film of the desired material. The chemical vapor deposition process can deposit a variety of materials, including a wide range of insulating materials, most semiconductor materials, and metal materials.

CVD equipment usually includes a reaction chamber, which includes a chamber body and a chamber cover. A tray is provided in the reaction chamber, and one or more wafers are placed on the tray. A heater is also provided under the tray, and the tray evenly transfers the heat radiated by the heater to the wafer. A corrosion-resistant upper liner is also provided under the chamber cover, and a reaction area is formed between the lower surface of the upper liner and the upper surface of the tray.

The inlet device (opposite to the center area of the tray) is fixedly installed on the top cover of the chamber through the upper liner. The process gas is introduced from the inlet device into the reaction area to process the wafer placed on the tray. During the process, the tray drives the wafer to rotate at high speed, so that different types of process gases reaching the upper surface of the tray are fully mixed under the drive of the high-speed rotating tray. The process gas reacts at a specific temperature and deposits on the surface of the wafer W to form a thin film of the required material. The wafer temperature is one of the important factors affecting the rate of material deposition on the wafer W.

In order to make the process gas flowing out of the inlet device pass through the upper surface of the wafer evenly in a laminar flow, the upper liner is usually parallel to the tray. However, as the process gas flows outward along the radial direction of the tray, the density of the process gas gradually decreases, affecting the growth rate of the film. In order to ensure the growth rate of the film, a large amount of process gas needs to be provided to the reaction chamber, resulting in a low utilization rate of the process gas. Especially when producing wafers with larger diameters, the waste of process gas is particularly prominent.

How to improve the utilization rate of process gases and the growth rate of thin films, and ensure the consistency of thin films on the wafer surface, is a problem that needs to be solved urgently.

Utility Model Content

The purpose of the utility model is to provide a vapor deposition device, in which the upper liner is formed by rotating the second busbar or the third busbar around the central axis of the air intake device. The vertical distance between each point on the second busbar and the third busbar and the wafer bearing surface, and the horizontal distance between each point and the central axis of the air intake device meet the set conditions. By changing the morphology of the upper liner, the utilization rate of the process gas in the reaction chamber (also known as improving the source efficiency) and the deposition rate of the thin film on the wafer surface are greatly improved, while also taking into account the consistency of the thickness of the thin film on the wafer surface. The vapor deposition device of the utility model can quickly grow a high-quality thin film on the wafer surface while consuming less process gas.

In order to achieve the above object, the utility model provides a vapor deposition device, comprising a reaction chamber, a tray is provided at the bottom of the reaction chamber, and the upper surface of the tray is a wafer carrying surface. The vapor deposition device comprises:

An upper liner, which is arranged in the reaction chamber and opposite to the wafer carrying surface, and a reaction area is formed between the upper liner and the wafer carrying surface;

an air inlet device, the air inlet device being used to inject process gas laterally into the reaction zone;

The upper pad is formed by rotating the second busbar around the central axis of the air inlet device, the second busbar is formed by rotating the first busbar around its starting point in the vertical direction by a set angle, the first busbar has the starting point close to the central axis and the end point far away from the central axis; points x and y are any two points on the first busbar, the vertical distances between points x and y and the wafer bearing surface are recorded as h ₁ and h ₂ respectively, the horizontal distances between points x and y and the central axis are recorded as l ₁ and l ₂ respectively, and points x and y satisfy h ₁ ×l ₁ =h ₂ ×l ₂ ,

Alternatively, the upper gasket is formed by rotating a third busbar around a central axis of the air intake device, the third busbar is a straight line, and the third busbar shares the starting point and the end point with the first busbar.

Optionally, the angle is [-2°, 5°], which defines that when the first busbar rotates around the starting point toward the direction close to the wafer carrying surface, the angle is a negative value, and when the first busbar rotates around the starting point toward the direction away from the wafer carrying surface, the angle is a positive value.

Optionally, the reaction chamber includes a chamber top cover, which is located above the upper liner; a cooling fluid channel is provided in the chamber top cover.

Optionally, a heating device is provided under the tray; along the radial direction of the tray, the tray is virtually divided into a plurality of annular temperature zones, and the temperature difference between adjacent annular temperature zones exceeds a set temperature difference threshold; along the radial direction of the chamber top cover, the chamber top cover is virtually divided into a plurality of annular temperature adjustment zones corresponding to the plurality of annular temperature zones respectively; the distance between the cooling fluid channel in the annular temperature adjustment zone and the lower surface of the chamber top cover depends on the temperature of the corresponding annular temperature zone.

Optionally, a temperature regulating mechanism is provided between the chamber top cover and the upper liner.

Optionally, the temperature adjustment mechanism includes a heat conducting plate; the upper surface of the heat conducting plate is in contact with the lower surface of the chamber top cover.

Optionally, the temperature adjustment mechanism further includes a gap formed between the heat conducting plate and the upper pad.

Optionally, the gap first becomes smaller and then becomes larger in a direction away from the air intake device.

Optionally, along the direction away from the air intake device, the thickness of the heat conducting plate first becomes thicker and then becomes thinner.

Optionally, along the direction away from the air intake device, the surface emission of the heat conducting plate first increases and then decreases.

Optionally, the vapor deposition equipment further comprises a heat transfer gas input end and a heat transfer gas output end, for providing flowing heat transfer gas to the gap.

Optionally, the composition of the heat transfer gas is adjustable.

Optionally, the vapor deposition equipment further comprises an exhaust ring, which is arranged around the lower side of the tray.

Optionally, the air pumping ring includes an inner ring, an outer ring and a ring top surface connecting the inner ring and the outer ring; and a plurality of air pumping holes are opened on the ring top surface along the circumferential direction of the air pumping ring.

Optionally, the vapor deposition equipment further comprises a side wall liner, wherein the side wall liner is arranged around the outer circumference of the tray, and the side wall liner is located between the upper liner and the vacuum ring.

Optionally, the upper end of the side wall liner has an airflow guide portion extending toward the air intake device.

Optionally, the upper pad further includes an upper pad bearing portion extending from the end point in a direction away from the central axis, and a bottom surface of the upper pad bearing portion is in contact with a top surface of the airflow guiding portion.

Optionally, the air inlet device includes air outlets located at different heights, and the air outlet closest to the upper pad is used to supply inactive gas.

The utility model also provides an upper liner, the upper liner is used for a vapor deposition device, the vapor deposition device comprises a reaction chamber, a tray is provided below the reaction chamber, and the upper surface of the tray is a wafer bearing surface;

The upper liner is arranged in the reaction chamber and is opposite to the wafer carrying surface, and a reaction area is formed between the upper liner and the wafer carrying surface; the thickness of the upper liner is greater than 2 mm;

The vapor deposition apparatus further comprises a gas inlet device, the gas inlet device being used to inject process gas laterally into the reaction area;

The upper pad is formed by rotating the second busbar around the central axis of the air inlet device, the second busbar is formed by rotating the first busbar around its starting point in the vertical direction by a set angle, the first busbar has the starting point close to the central axis and the end point far away from the central axis; points x and y are any two points on the first busbar, the vertical distances between points x and y and the wafer bearing surface are recorded as h ₁ and h ₂ respectively, the horizontal distances between points x and y and the central axis are recorded as l ₁ and l ₂ respectively, and points x and y satisfy h ₁ ×l ₁ =h ₂ ×l ₂ ,

Alternatively, the upper gasket is formed by rotating a third busbar around a central axis of the air intake device, the third busbar is a straight line, and the third busbar shares the starting point and the end point with the first busbar.

Optionally, the angle is [-2°, 5°], which defines that when the first busbar rotates around the starting point toward the direction close to the wafer carrying surface, the angle is a negative value, and when the first busbar rotates around the starting point toward the direction away from the wafer carrying surface, the angle is a positive value.

Compared with the prior art, the beneficial effects of the present invention are:

1) The upper liner of the vapor deposition equipment of the utility model is formed by rotating the second busbar/third busbar around the central axis of the air intake device. The vertical distance between each point on the second busbar/third busbar and the wafer bearing surface, and the horizontal distance between each point and the central axis of the air intake device meet the set conditions. By changing the morphology of the upper liner, the utilization rate of the process gas in the reaction chamber and the deposition rate of the thin film on the wafer surface are greatly improved, while also taking into account the consistency of the thickness of the thin film on the wafer surface. The vapor deposition equipment of the utility model can quickly grow a high-quality thin film on the wafer surface while consuming less process gas.

2) The chamber top cover of the utility model is provided with a cooling fluid channel, which can effectively remove the heat radiated from the tray and the wafer to the upper liner, reduce the deposition of the reaction gas on the surface of the upper liner, and thus effectively reduce the particle pollutants in the reaction chamber, significantly improving the wafer yield. At the same time, it can also reduce the cleaning frequency of the reaction chamber, greatly improve the wafer processing efficiency, and significantly reduce the wafer processing cost.

3) In the present invention, the tray is virtually divided into a plurality of annular temperature zones according to the temperature difference on the tray surface, and the chamber top cover is virtually divided into annular temperature adjustment zones corresponding to the plurality of annular temperature zones. If the temperature of the annular temperature zone is higher/lower, the distance between the cooling fluid channel in the corresponding annular temperature adjustment zone and the lower surface of the chamber top cover is closer/farther. In this way, the temperature of the upper liner can be adjusted by region, which is beneficial to reduce the temperature gradient of the upper liner and avoid deformation of the upper liner. By improving the consistency of the temperature of the upper liner, the consistency of the temperature of the process gas in the reaction chamber can also be improved (there is heat transfer between the upper liner and the process gas in the reaction chamber), which is beneficial to growing a thin film with uniform thickness on the surface of the wafer.

4) The utility model is provided with a temperature regulating mechanism between the chamber top cover and the upper liner, and the temperature regulating mechanism includes a heat conducting plate arranged between the chamber top cover and the upper liner, and a gap formed between the heat conducting plate and the upper liner. The heat transfer between the upper liner and the chamber top cover is enhanced by the heat conducting plate and the heat transfer gas in the gap, which is conducive to conducting the heat of the upper liner and preventing the deposition of a film on the surface of the upper liner.

5) Along the direction away from the air inlet device, the thickness, surface emissivity and gap size of the heat conduction plate in the utility model change with the temperature of the tray, so as to adjust the temperature of the upper liner by area and ensure the consistency of the temperature of the upper liner.

6) In the present invention, the composition of the heat transfer gas can be adjusted in real time according to the process and temperature in the reaction chamber, thereby adjusting the temperature of the upper liner in real time. In the deposition process of different materials, the deposits on the upper liner can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solution of the utility model, the following is a brief introduction to the drawings required for the description. Obviously, the drawings described below are an embodiment of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work:

FIG1 is a schematic diagram of a vapor deposition apparatus;

Fig. 2 is the A-A view of Fig. 1;

FIG3 is a schematic diagram of a vapor deposition device in Embodiment 1 of the present invention;

FIG4 is a schematic diagram of an air intake device in Embodiment 1 of the present utility model;

FIG5 is a top view of the tray, the side wall gasket, and the air pumping ring in the first embodiment of the present utility model;

FIG6 is a schematic diagram of the first busbar, the second busbar, and the third busbar in Embodiment 1 and Embodiment 2 of the present utility model;

FIG7 is a schematic diagram of a horizontal straight line for generating an upper liner of the vapor deposition apparatus of FIG1 ;

FIG8 is a comparison diagram of average growth rate of thin films on wafer surfaces and differences in film consistency in multiple embodiments;

FIG9 is a schematic diagram of the deposition rate of a thin film on a wafer surface along the radial direction of the wafer in multiple embodiments;

FIG10 is a schematic diagram of dividing the tray into a plurality of annular temperature zones and the chamber top cover into a plurality of annular temperature adjustment zones in Embodiment 3 of the present invention;

FIG. 11 is a schematic diagram of a heat conducting plate with a gradually varying thickness in Embodiment 4 of the present invention.

DETAILED DESCRIPTION

The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

It should be understood that when used in this specification and the appended claims, the term "comprising" indicates the presence of described features, integers, steps, operations, elements and/or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and/or groups thereof.

It should also be understood that the terms used in this application specification are only for the purpose of describing specific embodiments and are not intended to limit the application. As used in this application specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

It should be further understood that the term “and/or” used in the specification and appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

As used in this specification and the appended claims, the term "if" may be interpreted as "when" or "upon" or "in response to determining" or "in response to detecting," depending on the context. Similarly, the phrases "if it is determined" or "if [described condition or event] is detected" may be interpreted as meaning "upon determination" or "in response to determining" or "upon detection of [described condition or event]" or "in response to detecting [described condition or event]," depending on the context.

In addition, in the description of the present application, the terms "first", "second", "third", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

FIG. 1 is a vapor deposition device 1, which has a reaction chamber 100, in which a wafer W can be processed. The reaction chamber 100 includes a chamber cover 101 and a chamber body 102. The chamber cover 101 covers the chamber body 102, and the chamber cover 101 and the chamber body 102 together form an airtight internal processing space. The chamber cover 101 is usually made of metal material (such as stainless steel). Although the chamber body 102 shown in FIG. 1 is cylindrical, it can also be other shapes, such as square, hexagonal, octagonal or any other suitable shape.

As shown in FIG1 , the top of the gas inlet device 107 (usually made of corrosion-resistant stainless steel with good thermal conductivity) is penetrated by a chamber top cover and is located in the reaction chamber 100. The tray 109 is arranged below the gas inlet device 107 and opposite to the gas inlet device 107, and the upper surface of the tray 109 is a wafer carrying surface 1091. A reaction area is formed between the wafer carrying surface 1091 and the chamber top cover 101. The gas path of the gas inlet device 107 is connected to an external process gas supply device (not shown in the figure) for conveying process gas into the reaction area. The process gas may include a carrier gas (carrier gas) and a process gas, and the process gas may include a group III gas and a group V gas. In a typical metal organic chemical vapor deposition process, the carrier gas may be a gas such as nitrogen, hydrogen or argon.

The material of the tray 109 is usually graphite, which has good thermal conductivity. A heating element 120 is provided under the tray, and the tray 109 is heated by the heating element 120. The tray 109 then transfers the heat energy provided by the heating element 120 to the wafer W. The process gas reacts at a specific temperature and is deposited on the wafer W to form a thin film of the desired material.

The bottom of the tray 109 is fixedly connected to a driving shaft 104 (which can be driven by an external motor or cylinder), and the bottom of the driving shaft 104 vertically passes through the bottom wall of the chamber body 102 and is located outside the reaction chamber 100. The driving shaft 104 drives the tray 109 to rotate at a high speed, so that different types of process gases reaching the upper surface of the tray 109 are fully mixed under the driving of the high-speed rotating tray 109.

The exhaust device 103 is used to exhaust the gas in the reaction chamber 100, including the waste gas generated by the reaction and part of the process gas that does not have time to participate in the reaction.

The upper liner 106 is arranged below the chamber top cover 101, and is used to isolate the heat radiated from the reaction chamber 100 to the chamber top cover 101, and to prevent the formation of deposits on the chamber top cover 101. The material of the upper liner 106 can be graphite. The thickness of the upper liner 106 is generally greater than 2mm to provide sufficient rigidity. The chamber top cover 101 and the upper liner 106 in FIG. 1 both have a flat plate structure, which can avoid the existence of large-scale vertical diffusion airflow in the reaction chamber 100, ensure that the airflow in the reaction chamber 100 is in a horizontal flow state, and improve the uniformity of the airflow distribution in the reaction chamber 100.

From the inside to the outside, along the radial direction of the tray 109, the area of the process gas flow section 108 gradually increases. The flow section 108 is a cylindrical section with the same central axis as the gas inlet device 107 in the reaction chamber 100, and the top and bottom of the cylindrical section fall on the upper pad 106 and the wafer support surface 1091 respectively. As shown in Figures 1 and 2, when the horizontal distance between the flow section 108 and the central axis of the gas inlet device is l, the area of the flow section 108 is s=2π×l×h, where h represents the height of the flow section 108. When the upper pad 106 is a flat plate structure, h is the vertical distance between the upper pad 106 and the wafer support surface 1091.

As the process gas flowing out of the gas inlet device 107 flows in a direction away from the gas inlet device 107, the flow cross section 108 gradually increases, so the density of the process gas gradually decreases, and the deposition speed of the film also becomes slower. In order to prevent the process gas inside the reaction chamber 100 from becoming gradually thinner in its flow direction, it is necessary to increase the amount of process gas added, which results in the amount of process gas added being much larger than the amount required for the actual reaction, resulting in waste.

On the other hand, the upper liner 106 is subjected to greater heat radiation, and the process gas is easily deposited on the surface of the upper liner 106. After the deposits on the surface of the upper liner 106 are peeled off, particle contaminants are easily formed in the reaction chamber 100, which greatly reduces the yield of the wafer W.

The utility model provides a vapor deposition device, the upper pad of which is formed by rotating the second busbar or the third busbar around the central axis of the air intake device 107. The vertical distance between each point on the second busbar and the third busbar and the wafer bearing surface 1091, and the horizontal distance between each point and the central axis of the air intake device meet the set conditions. The utility model greatly improves the utilization rate of the process gas in the reaction chamber 100 and the deposition rate of the thin film on the wafer surface by changing the morphology of the upper pad 106, while also taking into account the consistency of the thickness of the thin film on the wafer surface. The vapor deposition device of the utility model can quickly grow a high-quality thin film on the wafer surface. At the same time, the utility model can also adjust the temperature of the upper pad 106 according to the region, quickly conduct the heat of the upper pad 106, and also improve the consistency of the temperature of the upper pad 106, which not only greatly reduces the deposits on the surface of the upper pad 106, but also can avoid the deformation and damage of the upper pad 106 due to thermal stress.

Embodiment 1

The utility model provides a vapor deposition device 2, as shown in FIG3, comprising a reaction chamber 200. The reaction chamber 200 comprises a chamber top cover 201 and a chamber body 202. The reaction chamber 200 is provided with a tray 209, an air inlet device 207, an upper liner 206, an exhaust ring 230, and a side wall liner 270, and the chamber top cover 201 is located above the upper liner 206.

The tray 209 is disposed at the bottom of the reaction chamber 200, and the upper surface of the tray 209 is a wafer carrying surface 2091. The upper pad 206 is opposite to the wafer carrying surface 2091, and a reaction area C is formed between the upper pad 206 and the wafer carrying surface 2091. A heating device 220 is disposed below the tray 209, and the heat energy provided by the heating device 220 is transferred to the wafer W through the tray 209, and the process gas reacts at a specific temperature and is deposited on the wafer W to form a thin film of a desired material.

In this embodiment, as shown in FIG3 , a plurality of recesses are provided on the upper surface of the tray 209 along the circumferential direction of the tray 209, and a plurality of wafer carriers 205 for placing wafers W are respectively arranged in the plurality of recesses. A special airway (not shown in the figure) is provided in the recess, and the airway is used to pass a gas of a certain pressure between the wafer carrier 205 and the tray 209, so that the wafer carrier 205 can be lifted up by the air pressure and separated from the surface of the tray, and then rotate around its center after being suspended at a certain height. A driving shaft 204 is fixedly connected to the bottom of the tray 209, which is used to drive the tray 209 to drive the wafer carrier 205 to rotate at high speed around the center of the tray. By driving the wafer carrier 205 to rotate and revolve, different types of process gases reaching the upper surface of the wafer are deposited on the wafer W in a uniform distribution.

As shown in FIG4 , the air inlet device 207 has a plurality of air inlet pipelines 2071 inside. The air inlet end 20711 of the air inlet pipeline 2071 is connected to an external process gas supply device (not shown in the figure). The air outlet end 20712 of the air inlet pipeline 2071 has a horizontal straight-line structure (its length direction is parallel to the radial direction of the tray 209), which is used to inject process gas into the reaction area C laterally, so that the process gas passes through the wafer surface as horizontally as possible and is evenly distributed on the wafer surface to improve the uniformity of the thin film deposited on the wafer surface. The air outlet ends 20712 of different types of process gases have different heights, so that multiple process gases can be injected into the reaction chamber 200 in layers in the vertical direction to prevent the multiple process gases from reacting prematurely before reaching the surface of the wafer W.

As shown in FIG3 and FIG5, the exhaust ring 230 is disposed around the lower side of the tray 209. The exhaust ring 230 includes an inner ring 231, an outer ring 232, and a ring top surface 233 connecting the inner ring and the outer ring. As shown in FIG5, along the circumferential direction of the exhaust ring 230, a plurality of exhaust holes 235 are opened on the ring top surface 233. The gas in the reaction chamber 200 is discharged to the outside of the reaction chamber 200 through the exhaust ring 230 and the exhaust device in sequence.

As shown in FIG3 and FIG5, the side wall gasket 270 is arranged around the outer circumference of the tray 209 and is located between the upper gasket 206 and the pumping ring 230. The side wall gasket 270 prevents the process gas from being deposited on the inner side wall of the reaction chamber 200. In this embodiment, as shown in FIG3, the side wall gasket 270 has an airflow guide portion 271 extending toward the air inlet device 207. The airflow guide portion 271 has an annular structure, and its inner diameter gradually increases from top to bottom. The process gas is guided to the pumping ring 230 through the airflow guide portion 271.

In this embodiment, the upper pad 206 is formed by rotating the first busbar ① around the central axis of the air inlet device 207. As shown in FIG6 , the first busbar ① has a starting point close to the central axis and an end point O' away from the central axis, and the starting point is the end point of the upper pad 206 closest to the air inlet device 207. Points x and y are any two points on the first busbar ①, and the vertical distances between points x and y and the wafer bearing surface 2091 are recorded as h ₁ and h ₂ , respectively, and the horizontal distances between points x and y and the central axis of the air inlet device are recorded as l ₁ and l ₂ , respectively, and points x and y satisfy h ₁ ×l ₁ =h ₂ ×l ₂ .

In this embodiment, as shown in FIG. 3 , the end point O' falls on the top surface of the airflow guide portion 271. Along the direction parallel to the radial direction of the tray, a horizontal section is horizontally extended outward from the end point O', and the horizontal section rotates around the central axis of the air intake device 207 to form an annular upper pad bearing portion 2061. The bottom surface of the upper pad bearing portion 2061 fits the top surface of the airflow guide portion 271, and the airflow guide portion 271 provides support for the upper pad bearing portion 2061. It is worth mentioning that the bottom surface of the upper pad bearing portion 2061 and the top surface of the side wall pad 270 may not be horizontal planes, as long as the two can be guaranteed to fit each other.

As shown in FIG3 , the flow cross section 208 of the process gas is a cylindrical cross section in the reaction chamber 200 with the same central axis as the gas inlet device 207, and the top and bottom of the flow cross section 208 fall on the upper pad 206 and the wafer carrying surface 2091 respectively. It is easy to understand that the flow cross section 208 corresponding to point x and the flow cross section 208 corresponding to point y have the same area S, S=2π×h ₁ ×l ₁ . That is to say, through the upper pad 206 generated by the first busbar ① in the utility model, the flow cross section area of the process gas is equal everywhere in the radial direction of the tray 209. Therefore, in this embodiment, in the direction away from the gas inlet device 207, the concentration gradient of the process gas is small (the reduction in the concentration of the process gas is mainly due to the continuous reaction and deposition of the process gas during the flow process). The utility model greatly improves the utilization rate of the process gas, reduces the amount of process gas used, and significantly reduces the cost of wafer W processing.

In another embodiment, the inactive gas may be made to flow into the reaction region C from the gas outlet 20712 closest to the upper liner 206, so that a separation layer is formed between the process gas involved in the reaction and the upper liner 206. This not only helps to reduce the deposits on the surface of the upper liner 206, but also forces the process gas involved in the reaction to be closer to the wafer surface, thereby improving the utilization rate of the process gas.

The rate of chemical reaction on the wafer surface is affected by the concentration of process gas on the wafer surface. In this embodiment, the distance between the upper pad 206 and the wafer bearing surface 2091 gradually decreases in the direction away from the air inlet device 207, and the process gas flowing out of the air inlet device 207 is forced by the upper pad 206 to flow toward the wafer bearing surface 2091. The process gas originally transported in the horizontal direction obtains a velocity component in the vertical direction, so that more process gas is transported to the wafer surface to participate in the chemical reaction on the wafer surface. Therefore, the deposition rate of the thin film on the wafer surface is improved by the utility model.

In an experiment, a thin film of the same material is deposited on a wafer W of the same size (wafer W rotates while revolving with the tray 209) by using a vapor deposition device 1 with a flat upper pad 106 and a vapor deposition device 2 of this embodiment (the upper pad 206 is generated by the first busbar ①). In this experiment, the reaction chamber 200 of the vapor deposition device 1 and the vapor deposition device 2 have the same diameter, and both use trays of the same size. In this experiment, the wafer diameter is about 150 mm. In the vapor deposition device 1, the vertical distance between the upper pad 106 and the wafer bearing surface 2091 is the same as the vertical distance between the starting point O of the upper pad 206 in the vapor deposition device 2 and the wafer bearing surface 2091. It should be emphasized that the above data is only used as an example and is not intended to be a limitation of the present utility model.

As shown in FIG7 , the flat upper pad 106 of the vapor deposition device 1 can be regarded as being formed by rotating a horizontal straight line (base) around the central axis of the air inlet device 107. When the upper pad 106 is rotated from a horizontal straight line, as shown in FIG8 , the average growth rate of the film on the wafer surface is 2.5896um/h, and the film thickness consistency difference is 3.16%. The calculation formula for the film thickness consistency difference is (GR _max -GR _min )/GR _ave /2, where GR _max and GR _min are the maximum and minimum growth rates of the film on the wafer surface, respectively, and GR _ave is the average growth rate of the film on the wafer surface. Ideally, we hope that the average growth rate of the film is as high as possible and the film thickness consistency difference is as small as possible.

In the above experiment, when the upper pad 206 obtained from the first busbar ① is used for the CVD process, as shown in Figure 8, the average growth rate of the film on the wafer surface is 3.0192um/h, and the film thickness consistency difference is 3.18%. As shown in Figure 9, at each position in the radial direction of the wafer, the film growth rate corresponding to the first busbar ① is always higher than the film growth rate corresponding to the horizontal straight line base. The above data show that the vapor deposition equipment 2 of this embodiment significantly improves the film growth rate while taking into account the consistency of the film thickness on the wafer surface. The vapor deposition equipment 2 can quickly grow high-quality films on the wafer surface.

In the present invention, the upper pad 206 can also be formed by rotating the second busbar around the central axis of the air intake device 207. The second busbar is formed by rotating the first busbar ① around its starting point O in the vertical direction at a set angle. Definition: When the first busbar ① rotates around its starting point O in a direction close to the wafer bearing surface 2091, the angle is a negative value; when the first busbar ① rotates around its starting point O in a direction away from the wafer bearing surface 2091, the angle is a positive value. In the present invention, the angle is [-2°, 5°], including -2°, (-2°, 0°), 0°, (0°, 5°), 5°, (-2°, 5°), etc.

In another embodiment, as shown in FIG6 , the second busbar ② is obtained by rotating the first busbar ① by -2°. In this embodiment, the area of the flow cross section 208 gradually decreases (less than S) along the direction away from the gas inlet device 207. Compared with the upper liner 206 generated by the first busbar ①, the upper liner 206 of this embodiment can transport more process gas to the wafer surface, which can not only further reduce the amount of process gas input, but also further increase the average growth rate of the film on the wafer surface.

As shown in Figure 9, at each position in the radial direction of the wafer, the film growth rate corresponding to the second busbar ② is always higher than the film growth rate corresponding to the first busbar ①. As shown in Figure 8, the average growth rate of the film on the wafer surface corresponding to the second busbar ② is 3.1660um/h, and the film thickness consistency difference is 4.13%. It can also be seen that compared with the film thickness consistency difference (3.67%) corresponding to the first busbar ①, the film thickness consistency difference corresponding to the second busbar ② is slightly increased, but within an acceptable range.

In another embodiment, as shown in FIG6 , the second busbar ③ is obtained by rotating the first busbar ① by 5°. As shown in FIG9 , at each position in the radial direction of the wafer, the film growth rate corresponding to the second busbar ③ is always lower than the film growth rate corresponding to the first busbar ①. In this embodiment, although the area of the flow cross section 208 still gradually increases in the direction away from the air inlet device 207, compared with the use of a flat upper liner 106, the amount of process gas delivered can still be reduced and the source efficiency of the process gas can be improved. In this embodiment, as shown in FIG8 , the average growth rate of the film on the wafer surface is 2.6786um/h, and the film thickness consistency difference is 2.37%. Compared with the use of a flat upper liner, this embodiment not only improves the average growth rate of the film on the wafer surface, but also reduces the film thickness consistency difference, and is a preferred embodiment.

Embodiment 2

The upper gasket 206 of this embodiment is formed by rotating the third busbar ④ around the central axis of the air intake device 207. As shown in Figure 6, the third busbar ④ is a straight line. The third busbar ④ shares the starting point O and the end point O' with the first busbar ①. The third busbar ④ is located between the first busbar ① and the second busbar ③.

As shown in Figure 9, at various positions in the radial direction of the wafer, the film growth rate corresponding to the third busbar ④ is lower than the film growth rate corresponding to the first busbar ①, and higher than the film growth rate corresponding to the second busbar ③. As shown in Figure 8, the average film growth rate corresponding to the third busbar ④ is 2.9127um/h, and the film thickness consistency difference is 3.67%.

Compared with the flat-type upper liner 106, the upper liner 206 generated by the third busbar ④ increases the process gas source efficiency and improves the film deposition rate on the wafer surface, while having a small and negligible impact on the consistency of the film thickness on the wafer surface.

Embodiment 3

In this embodiment, as shown in FIG. 3 and FIG. 10 , a cooling fluid channel 2011 is provided in the chamber top cover 201. Since there is good heat transfer between the chamber top cover 201 and the upper liner 206, the temperature of the chamber top cover 201 and the upper liner 206 can be adjusted through the cooling fluid channel 2011. Ideally, it is hoped that the temperature of the upper liner 206 is about 100 to 200 degrees lower than the tray temperature. On the one hand, the film deposition on the surface of the upper liner 206 can be reduced, thereby effectively reducing the particle contaminants in the reaction chamber 200, thereby achieving the purpose of improving the yield of the wafer W and reducing the cleaning frequency of the reaction chamber 200. On the other hand, there is also heat transfer between the upper liner 206 and the process gas in the reaction chamber 200. By controlling the temperature of the upper liner 206, it can be avoided that the temperature of the process gas in the reaction chamber 200 cannot meet the process requirements due to the excessively low temperature of the upper liner 206.

Due to the heat conduction caused by the gas flow and the presence of the cooling channel in the cavity, it is inevitable that the thermal conductivity of each area of the tray 209 is greatly different. In this embodiment, based on the temperature distribution of the tray 209 during the process, the tray 209 is virtually divided into a plurality of concentric annular temperature zones along the radial direction of the tray 209, and the temperature difference between adjacent annular temperature zones exceeds the set temperature difference threshold. As shown in FIG. 10, in this embodiment, the tray is divided into three annular temperature zones _D1 , _D2 , and _D3 . The number of annular temperature zones is only used as an example and is not a limitation of the present invention.

Along the radial direction of the chamber top cover 201, the chamber top cover 201 is virtually divided into a plurality of annular temperature adjustment zones corresponding to the plurality of annular temperature zones. Each annular temperature zone radiates different amounts of heat to the annular region corresponding to the upper liner. The distance between the cooling fluid channel 2011 in the annular temperature adjustment zone and the lower surface of the chamber top cover 201 depends on the temperature of the corresponding annular temperature zone. As shown in FIG10, in this embodiment, the chamber top cover 201 is divided into three annular temperature adjustment zones _G1 , _G2 , and _G3 .

As shown in FIG10 , the temperature of the annular temperature zone D ₂ is the highest, and the distance between the cooling fluid channel 2011 in the corresponding annular temperature adjustment zone G ₂ and the lower surface of the chamber top cover 201 is the shortest. The temperature of the annular temperature zone D ₁ is the lowest, and the distance between the cooling fluid channel 2011 in the corresponding annular temperature adjustment zone G ₁ and the lower surface of the chamber top cover 201 is the farthest. In this way, the temperature of the upper liner 206 can be adjusted by region, which is conducive to reducing the temperature gradient of the upper liner 206 and avoiding deformation of the upper liner 206 due to thermal stress. By improving the consistency of the temperature of the upper liner 206, the consistency of the temperature of the process gas in the reaction chamber 200 can also be improved, which is beneficial to growing a thin film with uniform thickness on the surface of the wafer.

Embodiment 4

In this embodiment, a temperature regulating mechanism is provided between the chamber top cover 201 and the upper liner 206 to enhance the temperature regulating effect on the upper liner 206. As shown in FIG3 and FIG11, the temperature regulating mechanism includes a heat conducting plate 261 (made of aluminum or quartz), and the upper surface of the heat conducting plate 261 is attached to the lower surface of the chamber top cover 201.

As shown in FIGS. 3 and 11 , the temperature adjustment mechanism further includes a gap 262 formed between the heat conducting plate 261 and the upper liner 206. The vapor deposition apparatus further includes a heat transfer gas input end 2621, as shown in FIGS. 3 and 11 , the heat transfer gas input end 2621 penetrates the chamber top cover 201 and the heat conducting plate 261, and is used to provide heat transfer gas to the gap 262.

It is easy to understand that the thicker the heat conducting plate 261 is and the greater the surface emissivity of the heat conducting plate 261 is, the better the heat transfer effect of the heat conducting plate 261 is. Based on the temperature distribution characteristics of the tray 209, in this embodiment, as shown in FIG11, along the direction away from the air inlet device 207, the thickness of the heat conducting plate 261 first becomes thicker and then becomes thinner and/or the surface emissivity of the heat conducting plate 261 first becomes larger and then becomes smaller. Since the spacing between the chamber top cover 201 and the upper liner 206 is consistent everywhere, the gap 262 becomes smaller/larger when the heat conducting plate 261 becomes thicker/thinner. Therefore, along the direction away from the air inlet device 207, the gap 262 first becomes smaller and then becomes larger.

In this embodiment, the thickness of the heat conducting plate 261, the surface emissivity of the heat conducting plate 261, and the size of the gap 262 change with the temperature of the tray 209, which helps to adjust the temperature of the upper pad 206 by region, improve the temperature consistency of the upper pad 206, and avoid deformation and damage of the upper pad 206 due to excessive temperature gradient.

In another embodiment, the composition of the heat transfer gas is adjustable. For example, the heat transfer gas may include nitrogen and argon, and the two gases have different thermal conductivities. By adjusting the flow ratio of nitrogen to argon, the thermal conductivity of the heat transfer gas can be adjusted, thereby adjusting the temperature of the upper pad 206 in real time. In the deposition process of different materials, the upper pad 206 can be adjusted to different temperatures to reduce the deposits on the upper pad 206. In one embodiment, the flow ratio of nitrogen to argon ranges from 3:1 to 2:1 (this is only an example and is not a limitation of the present invention).

It should be understood that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

The above is only a specific implementation of the utility model, but the protection scope of the utility model is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the utility model, and these modifications or replacements should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model should be based on the protection scope of the claims.

Claims (20)

1. A vapor deposition device, comprising a reaction chamber, wherein a tray is provided below the reaction chamber, the upper surface of the tray is a wafer carrying surface, and the bottom of the tray is fixedly connected to a driving shaft, wherein the vapor deposition device comprises: An upper liner, which is arranged in the reaction chamber and opposite to the wafer carrying surface, and a reaction area is formed between the upper liner and the wafer carrying surface; an air inlet device, the air inlet device being used to inject process gas laterally into the reaction zone; The upper pad is formed by rotating the second busbar around the central axis of the air inlet device, the second busbar is formed by rotating the first busbar around its starting point in the vertical direction by a set angle, the first busbar has the starting point close to the central axis and the end point far away from the central axis; points x and y are any two points on the first busbar, the vertical distances between points x and y and the wafer bearing surface are recorded as h ₁ and h ₂ respectively, the horizontal distances between points x and y and the central axis are recorded as l ₁ and l ₂ respectively, and points x and y satisfy h ₁ ×l ₁ =h ₂ ×l ₂ , Alternatively, the upper gasket is formed by rotating a third busbar around a central axis of the air intake device, the third busbar is a straight line, and the third busbar shares the starting point and the end point with the first busbar. 2. The vapor deposition equipment as described in claim 1 is characterized in that the angle is [-2°, 5°], which defines that when the first busbar rotates around the starting point toward the direction close to the wafer carrying surface, the angle is a negative value, and when the first busbar rotates around the starting point toward the direction away from the wafer carrying surface, the angle is a positive value. 3. The vapor deposition equipment as described in claim 1 is characterized in that the reaction chamber includes a chamber top cover, which is located above the upper liner; and a cooling fluid channel is provided in the chamber top cover. 4. The vapor deposition equipment as described in claim 3 is characterized in that a heating device is provided under the tray; along the radial direction of the tray, the tray is virtually divided into a plurality of annular temperature zones, and the temperature difference between adjacent annular temperature zones exceeds a set temperature difference threshold; along the radial direction of the chamber top cover, the chamber top cover is virtually divided into a plurality of annular temperature adjustment zones corresponding to the plurality of annular temperature zones respectively; the distance between the cooling fluid channel in the annular temperature adjustment zone and the lower surface of the chamber top cover depends on the temperature of the corresponding annular temperature zone. 5. The vapor deposition equipment as described in claim 3 is characterized in that a temperature control mechanism is provided between the chamber top cover and the upper liner. 6. The vapor deposition equipment as described in claim 5 is characterized in that the temperature adjustment mechanism includes a heat conducting plate; the upper surface of the heat conducting plate is in contact with the lower surface of the chamber top cover. 7 . The vapor deposition apparatus according to claim 6 , wherein the temperature adjustment mechanism further comprises a gap formed between the heat conducting plate and the upper pad. 8. The vapor deposition device as described in claim 7 is characterized in that, along the direction away from the air inlet device, the gap first becomes smaller and then becomes larger. 9 . The vapor deposition device according to claim 8 , wherein the thickness of the heat conducting plate first becomes thicker and then becomes thinner in a direction away from the air inlet device. 10. The vapor deposition device according to claim 7, characterized in that, along the direction away from the air inlet device, the surface emission of the heat conducting plate first increases and then decreases. 11. The vapor deposition device according to any one of claims 7 to 10, characterized in that the vapor deposition device further comprises a heat transfer gas input end and a heat transfer gas output end for providing flowing heat transfer gas to the gap. 12. The vapor deposition apparatus of claim 11, wherein the composition of the heat transfer gas is adjustable. 13 . The vapor deposition apparatus according to claim 1 , further comprising an exhaust ring disposed around a lower side of the tray. 14. The vapor deposition equipment as described in claim 13 is characterized in that the exhaust ring comprises an inner ring, an outer ring and a ring top surface connecting the inner ring and the outer ring; and a plurality of exhaust holes are opened on the ring top surface along the circumferential direction of the exhaust ring. 15. The vapor deposition apparatus according to claim 13, characterized in that the vapor deposition apparatus further comprises a side wall gasket, wherein the side wall gasket is arranged around the periphery of the tray, and the side wall gasket is located between the upper gasket and the vacuum ring. 16. The vapor deposition apparatus according to claim 15, wherein the upper end of the side wall liner has an air flow guide extending toward the air inlet device. 17. The vapor deposition device as described in claim 16 is characterized in that the upper pad also includes an upper pad bearing portion extending from the end point in a direction away from the central axis, and the bottom surface of the upper pad bearing portion is in contact with the top surface of the airflow guiding portion. 18. The vapor deposition apparatus according to claim 1, wherein the gas inlet device comprises gas outlets at different heights, and the gas outlet closest to the upper pad is used to supply inactive gas. 19. An upper liner, the upper liner being used in a vapor deposition device, characterized in that the vapor deposition device comprises a reaction chamber, a tray is provided below the reaction chamber, and the upper surface of the tray is a wafer carrying surface; The upper liner is arranged in the reaction chamber and is opposite to the wafer carrying surface, and a reaction area is formed between the upper liner and the wafer carrying surface; the thickness of the upper liner is greater than 2 mm; The vapor deposition apparatus further comprises a gas inlet device, the gas inlet device being used to inject process gas laterally into the reaction area; The upper pad is formed by rotating the second busbar around the central axis of the air inlet device, the second busbar is formed by rotating the first busbar around its starting point in the vertical direction by a set angle, the first busbar has the starting point close to the central axis and the end point far away from the central axis; points x and y are any two points on the first busbar, the vertical distances between points x and y and the wafer bearing surface are recorded as h ₁ and h ₂ respectively, the horizontal distances between points x and y and the central axis are recorded as l ₁ and l ₂ respectively, and points x and y satisfy h ₁ ×l ₁ =h ₂ ×l ₂ , Alternatively, the upper gasket is formed by rotating a third busbar around a central axis of the air intake device, the third busbar is a straight line, and the third busbar shares the starting point and the end point with the first busbar. 20. The upper pad as described in claim 19 is characterized in that the angle is [-2°, 5°], which defines that when the first busbar rotates around the starting point toward the direction close to the wafer carrying surface, the angle is a negative value, and when the first busbar rotates around the starting point toward the direction away from the wafer carrying surface, the angle is a positive value.