Vapor deposition system, thermal expansion measurement method and process gap measurement method

Abstract

The invention discloses a method for measuring the thermal expansion amount of a heater, and the method comprises the steps: gradually reducing the distance between a wafer and the heater through a height adjustment assembly at a first temperature, maintaining the air exhaust of an air exhaust pipeline in the process, recording the air pressure value at the outlet of the air exhaust pipeline in real time, and when the air pressure value tends to be stable, determining the thermal expansion amount of the heater; acquiring a first position of the corresponding height adjusting assembly when a first air pressure value reaches a first saturation point at a first temperature; at the second temperature, the steps are repeated, and when the air pressure value at the outlet of the air exhaust pipeline tends to be stable, the second position of the height adjusting assembly corresponding to the second air pressure value at the second temperature when the second air pressure value reaches the second saturation point is obtained; the difference value between the first position and the second position is calculated, and the vertical thermal expansion amount of the heater between the first temperature and the second temperature is obtained; the method is simple to operate and accurate in measurement result, the internal structure of the reaction cavity does not need to be changed, and the thermal field distribution in the reaction cavity is not influenced.

Description

Technical Field

[0001] The invention relates to the field of semiconductor equipment, and in particular to a thin film vapor deposition system, a method for measuring thermal expansion of a heater, and a method for measuring a process gap between a gas shower head and a heater. Background Art

[0002] Thin film vapor deposition technology is a technology that deposits thin films on substrates, such as semiconductor wafers. Take the CVD (chemical vapor deposition) process as an example. Figure 1 As shown, a reaction chamber 100 of a CVD process is shown. The process is to pass a reaction gas containing thin film elements through a gas shower head 101 to above a wafer 200 in the reaction chamber 100. A heater 102 is also provided under the wafer 200 to provide heating, so that the reaction gas undergoes a chemical reaction on the surface of the wafer 200 to generate a thin film.

[0003] Thin film vapor deposition processes such as CVD are sensitive to the thermal and flow field environments in the reaction chamber, and the distance between the upper surface of the heater 102 and the lower surface of the gas shower head 101 (hereinafter referred to as the process gap) will have a certain impact on the thermal and flow field distribution in the reaction chamber 100. In order to speed up the wafer processing process during the process, multiple reaction chambers are usually used to process batches of wafers at the same time, or multiple chambers are used to process wafers in sequence with different processes. Therefore, in order to ensure the accuracy and composition uniformity of the processed wafers, it is necessary to control the consistency of the process gap when the same reaction chamber processes different batches of wafers and the consistency of the process gap between the reaction chambers performing the same processing process.

[0004] Due to the wafer processing process, such as CVD and other thin film vapor deposition technologies, the heater 102 needs to provide high-temperature heating. At high temperatures, the heater 102 will inevitably undergo thermal expansion, which will affect the process gap. In order to ensure that the process gap of the reaction chamber is consistent, it is necessary to determine the thermal expansion amount of the heater 102 at high temperature, and then control the process gap based on the thermal expansion amount of the heater.

[0005] At present, there are two methods for determining the thermal expansion of the heater: calculating based on the thermal expansion coefficient of the heater material to obtain the thermal expansion of the heater at high temperature. However, since the heater is not made of a single material, its actual raw material composition is complex and is usually not a regular shape structure in a strict sense. Therefore, the accuracy of this method is poor. The thermal expansion of the heater at high temperature obtained by theoretical calculation often has a certain deviation from the actual thermal expansion of the heater at high temperature, which affects the consistency of the process gap of the reaction chamber. In addition, there is also a method of measuring the thermal expansion of the heater at high temperature by infrared ranging. This method generally opens a hole in the chamber cover of the reaction chamber to set an infrared sensor, and uses the principle of optical path difference to measure the thermal expansion of the heater at high temperature. However, the infrared sensor is usually not resistant to high temperature, and this method also requires drilling a hole in the gas shower head, which not only changes the hardware structure in the reaction chamber, but also complicates the operation and damages the sealing environment of the reaction chamber. It is necessary to consider the sealing of the opening, which affects the thermal field distribution in the reaction chamber.

[0006] Therefore, it is very necessary to propose a method for measuring the thermal expansion of a heater that is easy to operate, accurate in measurement, and does not require changing the original structure of the reaction chamber. Summary of the invention

[0007] The purpose of the present invention is to provide a method for measuring the thermal expansion of a heater and a method for measuring the process gap between a gas shower head and a heater, which are simple to operate, accurate in measurement and do not require changing the original structure of the reaction chamber.

[0008] To achieve the above-mentioned objectives, the first aspect of the present invention proposes a thin film vapor deposition system, comprising: a reaction chamber, a gas shower head arranged in the reaction chamber, and a heater arranged opposite to the gas shower head, for carrying a wafer; an exhaust pipe is also arranged in the heater, an air pressure detection device is arranged on the exhaust pipe, and the exhaust pipe is used to suck the gas between the upper surface of the heater and the lower surface of the wafer; a height adjustment component is used to adjust the distance between the wafer and the heater; and also includes: a controller, the controller is used to record and store the vertical thermal expansion of the heater between the first temperature and the second temperature, and control the height adjustment component to compensate for the change in the process gap between the lower surface of the gas shower head and the upper surface of the heater caused by the thermal expansion.

[0009] Optionally, the controller is further configured to perform the following steps:

[0010] At a first temperature, the distance between the wafer and the heater is gradually reduced by the height adjustment component, during which air is extracted through the air extraction pipeline and a first air pressure value of the air pressure detection device is recorded in real time, and a first position of the height adjustment component corresponding to when the first air pressure value reaches a first saturation point at the first temperature is obtained;

[0011] At the second temperature, the distance between the wafer and the heater is gradually reduced by the height adjustment component, during which air is extracted through the exhaust pipe and the second air pressure value of the air pressure detection device is recorded in real time, and the second position of the height adjustment component corresponding to the second air pressure value reaching the second saturation point at the second temperature is obtained;

[0012] The difference between the first position and the second position is calculated to obtain the vertical thermal expansion amount of the heater between the first temperature and the second temperature.

[0013] Optionally, the surface of the heater is provided with a plurality of bosses and a sealing ring for sealing the upper surface of the heater and the lower surface of the wafer, and the gaps between the bosses, the sealing ring and the lower surface of the wafer are connected to the exhaust duct.

[0014] Optionally, a plurality of grooves are provided on the surface of the heater, and the plurality of grooves are connected to the air extraction pipe.

[0015] Optionally, the exhaust pipe is connected to a vacuum pump so that the pressure on the back side of the wafer is lower than the pressure on the front side of the wafer, and an airflow regulating device is also provided on the exhaust pipe.

[0016] Optionally, the height adjustment assembly includes: a driving device for controlling the lifting and lowering of the heater; and a plurality of ejector pin assemblies arranged through the heater, the ejector pin assemblies being used to support the wafer.

[0017] Optionally, the height adjustment assembly includes: a plurality of ejector pin assemblies disposed through the heater, the ejector pin assemblies being used to support the wafer; and a driving device for controlling the simultaneous lifting and lowering of the plurality of ejector pin assemblies.

[0018] Optionally, the driving device is a servo motor, and the stroke position of the servo motor is obtained as the first position and the second position of the height adjustment component.

[0019] Optionally, the first temperature is a temperature lower than 80° C., and the second temperature is a process temperature.

[0020] Optionally, the measurement method is repeated multiple times and an average value is taken as the final result.

[0021] A second aspect of the present invention provides a method for measuring the thermal expansion of a heater, wherein the heater is located in a reaction chamber of a thin film vapor deposition system, and the reaction chamber further includes: an exhaust pipe disposed between the heater and a wafer and connected to the outside of the reaction chamber, and a height adjustment component for adjusting the distance between the wafer and the heater, comprising the following steps:

[0022] At a first temperature, gradually reduce the distance between the wafer and the heater through the height adjustment component, keep the exhaust pipe to exhaust air during the process and record the air pressure value at the outlet of the exhaust pipe in real time, and when the air pressure value tends to be stable, obtain the first position of the height adjustment component corresponding to the first air pressure value reaching the first saturation point at the first temperature;

[0023] Repeat the above steps at the second temperature, and when the air pressure value at the outlet of the air extraction pipeline tends to be stable, obtain the second position of the height adjustment component corresponding to when the second air pressure value at the second temperature reaches the second saturation point;

[0024] The difference between the first position and the second position is calculated to obtain the vertical thermal expansion amount of the heater between the first temperature and the second temperature.

[0025] Optionally, the exhaust pipe is connected to a vacuum pump so that the pressure on the back side of the wafer is lower than the pressure on the front side of the wafer, and an airflow regulating device is also provided on the exhaust pipe.

[0026] Optionally, the height adjustment assembly includes: a driving device for controlling the lifting and lowering of the heater; and a plurality of ejector pin assemblies arranged through the heater, the ejector pin assemblies being used to support the wafer.

[0027] Optionally, the height adjustment assembly includes: a plurality of ejector pin assemblies disposed through the heater, the ejector pin assemblies being used to support the wafer; and a driving device for controlling the simultaneous lifting and lowering of the plurality of ejector pin assemblies.

[0028] Optionally, the driving device is a servo motor, and the stroke position of the servo motor is obtained as the first position and the second position of the height adjustment component.

[0029] Optionally, the first temperature is a temperature lower than 80° C., and the second temperature is a process temperature.

[0030] A third aspect of the present invention proposes a method for measuring a process gap between a gas shower head and a heater, comprising the following steps: obtaining a first process gap between the gas shower head and the heater at a first temperature, obtaining the thermal expansion between the first temperature and the second temperature according to the above-mentioned method for measuring the thermal expansion of the heater, calculating the difference between the first process gap and the thermal expansion, and obtaining a second process gap between the gas shower head and the heater at the second temperature.

[0031] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0032] This solution uses the existing reaction chamber structure to measure and determine the thermal expansion of the heater. Based on the principle of vacuum suction cup adsorbing wafers, by monitoring the gas state between the wafer and the heater, the position of the height adjustment component corresponding to the heater completely adsorbing the wafer at different temperatures is determined, and then the thermal expansion of the heater at different temperatures is calculated. This method is simple to operate, does not require changing the internal structure of the reaction chamber, and will not affect the thermal field distribution in the reaction chamber.

[0033] Compared with the theoretical calculation method, this solution measures the upper surface height of the heater at different temperatures in practice, and the measurement result is more accurate. Furthermore, by taking the average value of multiple measurements, the final result is more reliable, eliminating the randomness of a single measurement.

[0034] This solution ensures that the process gaps of various reaction chambers are consistent by measuring the thermal expansion of heaters and process gaps in different reaction chambers, which is beneficial to ensuring the accuracy and composition uniformity of processed wafers. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a schematic diagram of the overall structure of the reaction chamber of an embodiment of the present invention;

[0036] Figure 2 A schematic diagram of a partial structure of a reaction chamber according to an embodiment of the present invention;

[0037] Figure 3 A schematic diagram of the connection between the ejector assembly and the heater in one embodiment of the present invention;

[0038] Figure 4 is a flow chart of a method for measuring thermal expansion of a heater in one embodiment of the present invention;

[0039] Figure 5 A line graph of gas pressure values ​​at low temperature and process temperature in one embodiment of the present invention;

[0040] Figure 6 FIG. 4 is a schematic diagram of a partial structure of a reaction chamber according to another embodiment of the present invention. DETAILED DESCRIPTION

[0041] The following will be combined with the embodiments of the present invention Figure 1 to Figure 6 , the technical solutions, structural features, objectives achieved and effects in the embodiments of the present invention are described in detail.

[0042] It should be noted that the drawings are in a very simplified form and use non-precise proportions. They are only used to conveniently and clearly assist in explaining the embodiments of the present invention, and are not used to limit the conditions for the implementation of the present invention. Therefore, they have no substantive technical significance. Any structural modification, change in proportional relationship or adjustment of size, without affecting the effects and purposes that can be achieved by the present invention, should still fall within the scope of the technical content disclosed by the present invention.

[0043] It should be noted that, in the present invention, the terms "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or equipment including a series of elements includes not only the elements explicitly listed, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or equipment.

[0044] In the reaction chamber 100 of the thin film vapor deposition system, a deposition process such as CVD is performed. Figure 1 As shown, the reaction chamber 100 includes a gas shower head 101 disposed above the interior of the reaction chamber 100 and a heater 102 disposed opposite to the gas shower head 101. When the vapor deposition process is performed, the reaction gas is introduced into the top of the wafer 200 in the reaction chamber 100 through the gas shower head 101, and the heater 102 supports the wafer 200 and provides heating for it, so that the reaction gas undergoes a chemical reaction on the surface of the wafer 200 to form a thin film.

[0045] like Figure 2 As shown, a height adjustment component for adjusting the distance between the wafer 200 and the heater 102 is provided below the heater 102, and the height adjustment component includes a plurality of ejector pin components 103 arranged through the heater 102, and the ejector pin components 103 are used to support the wafer 200. The height adjustment component also includes a driving device 104 for controlling the simultaneous lifting and lowering of the ejector pin components 103; before the process is carried out, the ejector pin components 103 are controlled by the driving device 104 to rise to the wafer transfer position, so that the top of the ejector pin components 103 protrudes from the upper surface of the heater 102 to support the wafer 200, the wafer 200 is clamped by a robot and enters the reaction chamber 100, and is placed on the top of the ejector pin components 103 so that the ejector pin components 103 jointly support the wafer 200, and then the ejector pin components 103 are controlled by the driving device 104 to descend, so as to reduce the distance between the wafer 200 and the heater 102, until the top of the ejector pin components 103 reaches the upper surface of the heater 102; as shown Figure 3As shown, the heater 102 is provided with a plurality of through holes 1021, and the ejector pin assembly 103 passes through the through holes 1021. When the ejector pin assembly 103 descends to the process position, the upper surface of the ejector pin assembly 103 is lower than or level with the upper surface of the heater 102, so that the heater 102 can adsorb the wafer 200 for subsequent processes.

[0046] like Figure 2 As shown, the reaction chamber 100 further includes an exhaust pipe 105 disposed in the heater 102, the first end of which is connected to a vacuum pump 108, for extracting the gas between the upper surface of the heater 102 and the lower surface of the wafer 200, so that the pressure on the back of the wafer 200 is less than the pressure on the front of the wafer 200, and the wafer 200 is adsorbed on the upper surface of the heater 102 and does not fall off through the pressure difference; the vacuum pump 108 is disposed outside the reaction chamber 100 to provide exhaust power. The exhaust pipe 105 is also provided with an airflow regulating device 106 and an air pressure detection device 107, and the air pressure detection device 107 is used to obtain the air pressure value of the exhaust pipe 105 in real time.

[0047] The second end of the exhaust pipe 105 is connected to the exhaust gap between the upper surface of the heater 102 and the lower surface of the wafer 200. Specifically: the surface of the heater 102 is provided with a plurality of bosses and a sealing ring for sealing the upper surface of the heater 102 and the lower surface of the wafer 200, and the exhaust gap between the bosses, the sealing ring and the lower surface of the wafer 200 is connected to the exhaust pipe 105; or, in other embodiments, a plurality of grooves are provided on the surface of the heater 102, and the plurality of grooves are the exhaust gaps connected to the exhaust pipe 105.

[0048] The thin film vapor deposition system further includes a controller, which controls the lifting and lowering of the ejector pin assembly 103 through the driving device 104 , thereby adjusting the distance between the wafer 200 and the heater 102 .

[0049] In order to speed up the processing of wafers, multiple reaction chambers can be used to process batches of wafers at the same time, or multiple chambers can be used to process wafers in sequence with different processes. In order to ensure the accuracy and composition uniformity of the processed wafers, it is necessary to control the process gap (the distance between the upper surface of the heater 102 and the lower surface of the gas shower head 101) when the same reaction chamber processes different batches of wafers, and the process gap between each reaction chamber performing the same processing process is consistent. Since the heater 102 produces thermal expansion at high temperature, which affects the consistency of the process gap, this solution provides a method for measuring the thermal expansion of the heater of the reaction chamber. Based on the thermal expansion of the heater, the process gap of each reaction chamber can be controlled to be consistent.

[0050] The present embodiment discloses a method for measuring the thermal expansion of a heater without changing the internal structure of the reaction chamber 100. Figure 4 As shown, the following steps are included:

[0051] Step 1: At low temperature, the wafer 200 is introduced into the reaction chamber 100. The controller controls the ejector assembly 103 to carry the wafer 200 downward through the driving device 104. During the downward process, the exhaust pipe 105 is kept to exhaust air from between the wafer 200 and the heater 102, and the first air pressure value of the air pressure detection device 107 is recorded in real time. When the first air pressure value tends to be stable, the first saturation point of the first air pressure value is recorded, and the first position of the driving device 104 corresponding to the first air pressure value reaching the first saturation point is obtained.

[0052] Specifically, when performing the above steps, the reaction chamber 100 is at room temperature, generally a temperature below 80°C. At this low temperature, the heater 102 does not generate thermal expansion or its thermal expansion is negligible. Under conditions of less than 80°C, a test tool can be used to directly test the process gap under low temperature conditions, and use this process gap as a debugging benchmark. The test tool can be a wafer with a capacitive sensor installed inside, and the process gap is obtained by testing the capacitance value between the gas shower head and the heater. The test tool is not limited to wafers with capacitive sensors, as long as it is a test tool that can measure the vertical distance between the gas shower head and the heater under low temperature conditions. The controller controls the ejector pin assembly 103 to rise through the driving device 104, and then protrudes from the upper surface of the heater 102 and continues to rise until it reaches the wafer transfer position. At this wafer transfer position, the robot transfers the wafer 200 into the reaction chamber 100 through a transfer port opened on the side wall of the reaction chamber 100 and places it on the top of multiple ejector pin assemblies 103, so that the multiple ejector pin assemblies 103 jointly support the wafer 200. At this time, there is a certain distance between the wafer 200 and the heater 102.

[0053] In this embodiment, an air flow regulating device 106 and an air pressure detecting device 107 are also provided on the exhaust pipe. The air flow regulating device 106 is used to regulate the air flow between the back side of the wafer 200 and the upper surface of the heater 102. The air pressure detecting device 107 is used to obtain the air pressure value in the exhaust pipe 105. The air pressure detecting device 107 is arranged at the outlet of the exhaust pipe 105.

[0054] Although the present embodiment uses an independent airflow regulating device 106 and an air pressure detecting device 107, this is not a limitation of the present invention. In other embodiments, other devices having the functions of regulating airflow and detecting air pressure may be disposed on the exhaust duct 105.

[0055] In the process of the controller lowering the ejector assembly 103 through the driving device 104 to reduce the distance between the wafer 200 and the heater 102, the vacuum pump 108 and the exhaust pipe 105 continuously extract the gas between the wafer 200 and the heater 102, and the controller also records the reading of the air pressure detection device 107 as the first air pressure value in real time, and records the stroke position of the driving device 104 at the same time; as the ejector assembly 103 descends, the distance between the wafer 200 and the heater 102 is reduced, the gas that can be sucked between the two becomes less and less, and the reading of the air pressure detection device 107 becomes smaller and smaller; when the air pressure detection device 107 is lowered, the distance between the wafer 200 and the heater 102 is reduced, and the air that can be sucked between the two becomes less and less, and the reading of the air pressure detection device 107 becomes smaller and smaller; when the air pressure detection device When the reading of 107 tends to be stable, it means that there is almost no gas that can be extracted between the wafer 200 and the heater 102, that is, the distance between the wafer 200 and the heater 102 is zero, and the wafer 200 is adsorbed and tightly attached to the heater 102. At this time, the controller records the first position of the driving device 104 corresponding to the first air pressure value reaching the first saturation point. The first saturation point of the first air pressure value refers to the point at which the first air pressure value of the air pressure detection device 107 tends to be stable and reaches the saturation value at low temperature (<80°C). Under normal circumstances, the reading of the air pressure detection device 107 tends to be stable at 0 to 0.7 torr. Figure 5 As shown, the air pressure value line graph of the air pressure detection device 107 at low temperature tends to be stable from point A, so point A is the first saturation point of the first air pressure value at low temperature, and the horizontal coordinate corresponding to point A is the first position of the driving device 104 corresponding to the first saturation point of the first air pressure value.

[0056] In this embodiment, a servo motor is used as the driving device 104, wherein the stroke position of the servo motor is the position of the driving device 104. In other embodiments, any other driving component capable of recording its stroke can also be used as the driving device 104.

[0057] After obtaining the first position of the driving device 104 according to step 1, the controller controls the ejector assembly 103 to rise through the driving device 104, so that the ejector assembly 103 lifts the wafer 200 from the upper surface of the heater 102 until it reaches the wafer transfer position, and the robot transfers the wafer 200 out of the reaction chamber 100.

[0058] Step 2. Repeat the process of step 1 at the process temperature. Specifically, the controller controls the ejector assembly 103 to carry the wafer 200 downward through the driving device 104. During the downward process, the exhaust pipe 105 is kept to exhaust air from between the wafer 200 and the heater 102, and the second air pressure value of the air pressure detection device 107 is recorded in real time. When the second air pressure value tends to be stable, the controller records the second saturation point of the second air pressure value, and obtains the second position of the driving device 104 corresponding to the second air pressure value reaching the second saturation point.

[0059] Similar to step 1, before performing step 2, the temperature in the reaction chamber 100 is first raised to the process temperature and maintained. Different process processes have different process temperatures, usually above 250°C. At this process temperature, the heater 102 will generate thermal expansion. Then, the driving device 104 controls the ejector assembly 103 to rise to the wafer transfer position. At this wafer transfer position, the robot transfers the wafer 200 into the reaction chamber 100 and places it on the top of multiple ejector assemblies 103, so that the ejector assemblies 103 jointly support the wafer 200. At this time, there is a certain distance between the wafer 200 and the heater 102.

[0060] Similar to step one, when the controller lowers the ejector assembly 103 through the driving device 104 to reduce the distance between the wafer 200 and the heater 102, the vacuum pump 108 and the exhaust pipe 105 continuously suck the gas between the wafer 200 and the heater 102, and record the indication of the air pressure detection device 107 as the second air pressure value and the position of the driving device 104. When the indication of the air pressure detection device 107 tends to be stable, the controller records the second position of the driving device 104 corresponding to the second saturation point of the second air pressure value. The second saturation point of the second air pressure value refers to the point when the indication of the air pressure detection device 107 tends to be stable at the process temperature. The horizontal coordinate corresponding to the second saturation point of the second air pressure value is the second position of the driving device 104 corresponding to when the second air pressure value reaches the second saturation point.

[0061] After acquiring the second position, the driving device 104 controls the ejector assembly 103 to rise, so that the ejector assembly 103 lifts the wafer 200 from the upper surface of the heater 102 to the wafer transfer position, and the robot transfers the wafer 200 out of the reaction chamber 100 .

[0062] It should be noted that when performing the above thermal expansion measurement method, the wafer 200 used is a test wafer, not a process wafer for process reaction.

[0063] The processing of the above step 1 and step 2 is not in any particular order. In other embodiments, the second position of the driving device 104 corresponding to the saturation point of the air pressure value at the process temperature can be obtained first, and then the first position of the driving device 104 corresponding to the saturation point of the air pressure value at the low temperature can be obtained. It is only necessary to control the reaction chamber 100 at the corresponding temperature.

[0064] Step 3: The controller calculates the difference between the first position and the second position of the driving device 104 corresponding to the saturation point of the air pressure at low temperature and the process temperature, thereby obtaining the vertical thermal expansion of the heater 102 between the low temperature and the process temperature.

[0065] Since the first position and the second position record the positions of the driving device 104 when the heater 102 completely adsorbs the wafer 200 at both the low temperature and the process temperature, the controller calculates the difference between the first position of the driving device 104 corresponding to when the first air pressure value reaches the first saturation point and the second position of the driving device 104 corresponding to when the second air pressure value reaches the second saturation point, and the thermal expansion of the heater 102 in the vertical direction between the two temperatures can be obtained.

[0066] It should be noted that when performing the above-mentioned measurement process, the internal pressure of the reaction chamber 100 needs to be kept stable. For example, another exhaust pipe can be set on the side wall of the reaction chamber 100 to connect to another external vacuum pump to stabilize the pressure in the reaction chamber 100 at a fixed value greater than zero. In the above-mentioned embodiment, the internal pressure of the reaction chamber 100 is stabilized at 5 to 30 torr.

[0067] In order to obtain more accurate results and eliminate the randomness of the experiment, the above steps 1 to 3 are repeated multiple times to obtain the thermal expansion between multiple low temperatures and process temperatures, and the average value is calculated as the final result.

[0068] The controller is further used to record and store the thermal expansion of the heater 102 between the low temperature and the process temperature. The thermal expansion affects the size of the process gap in the reaction chamber 100. To ensure the consistency of the process gap, during the process, the controller controls the driving device 104 to compensate for the change in the process gap between the lower surface of the gas shower head 101 and the upper surface of the heater 102 caused by the thermal expansion.

[0069] This embodiment also discloses a thin film vapor deposition system, such as Figure 1 and Figure 2 As shown, it comprises: a reaction chamber 100, and a gas shower head 101 arranged in the reaction chamber 100, and a heater 102 arranged opposite to the gas shower head 101, the heater 102 is used to carry a wafer 200; a gas extraction pipeline 105 is also arranged in the heater 102, which is used to evacuate the space between the wafer 200 and the heater 102 to a vacuum; a height adjustment component is used to adjust the distance between the wafer 200 and the heater 102. The gas extraction pipeline 105 is used to extract the gas between the heater 102 and the lower surface of the wafer 200, and the first end thereof is connected to the vacuum pump 108, and the second end thereof is connected to the space between the upper surface of the heater 102 and the lower surface of the wafer 200; an airflow adjustment device 106 and an air pressure detection device 107 are arranged on the gas extraction pipeline 105.

[0070] Specifically: the surface of the heater 102 is provided with a plurality of bosses and a sealing ring for sealing the upper surface of the heater 102 and the lower surface of the wafer 200, and the exhaust gap between the bosses, the sealing ring and the lower surface of the wafer 200 is connected to the exhaust pipe 105; or, in other embodiments, a plurality of grooves are provided on the surface of the heater 102, and the plurality of grooves are connected to the exhaust pipe 105.

[0071] like Figure 2 As shown, the height adjustment assembly includes: a plurality of ejector pin assemblies 103 disposed through the heater 102 , the ejector pin assemblies 103 being used to support the wafer 200 ; and a driving device 104 for controlling the simultaneous lifting and lowering of the plurality of ejector pin assemblies 103 .

[0072] The thin film vapor deposition system also includes a controller, which controls the lifting and lowering of the ejector assembly 103 through the driving device 104, so as to adjust the distance between the wafer 200 and the heater 102 at the low temperature and the process temperature; the controller is also used to record the reading of the air pressure detection device 107. When the reading of the air pressure detection device 107 tends to be stable, that is, the air pressure value at the outlet of the exhaust pipe 105 tends to be stable, the controller obtains the first position of the driving device 104 corresponding to the first saturation point of the first air pressure value at the low temperature and the second position of the driving device 104 corresponding to the second saturation point of the second air pressure value at the process temperature, and calculates the difference between the first position and the second position, so as to obtain the vertical thermal expansion of the heater 102 between the low temperature and the process temperature.

[0073] The controller is further used to record and store the thermal expansion amount of the heater 102 between the low temperature and the process temperature, and control the driving device 104 to compensate for the change of the process gap caused by the thermal expansion amount.

[0074] This embodiment also provides a method for measuring a process gap between a gas shower head 101 and a heater 102, comprising the following steps: obtaining a first process gap between the gas shower head 101 and the heater 102 at a low temperature, obtaining a thermal expansion amount of the heater 102 between the low temperature and the process temperature according to the above-mentioned method for measuring the thermal expansion amount of the heater, and calculating a difference between the first process gap and the thermal expansion amount, thereby obtaining a second process gap between the gas shower head 101 and the heater 102 at the process temperature.

[0075] Although this embodiment only measures the thermal expansion of the heater 102 between the low temperature and the process temperature and the process gap between the gas shower head 101 and the heater 102 at the process temperature, in other embodiments, when it is necessary to measure the thermal expansion of the heater between two or more other different temperatures and to measure the process gap between the gas shower head 101 and the heater 102 at other temperatures, the above method can still be used, and it is only necessary to control different measurement temperatures.

[0076] In another embodiment, other structures may be the same as those in the above embodiment, and only the specific structure and controller of the height adjustment assembly are different from those in the above embodiment, such as Figure 6 As shown, the height adjustment component includes a plurality of ejector pin assemblies 103 disposed through the heater 102, and the ejector pin assemblies 103 are used to support the wafer 200. The height adjustment component also includes a driving device 109 for controlling the rise and fall of the heater 102. Before the vapor deposition process is performed, the controller controls the heater 102 to descend to the wafer transfer position through the driving device 109, so that the top of the ejector pin assembly 103 protrudes from the upper surface of the heater 102 to support the wafer 200. After the wafer 200 is clamped by a robot and enters the reaction chamber 100 and is placed on the top of the ejector pin assemblies 103 so that the ejector pin assemblies 103 jointly support the wafer 200, the heater 102 is controlled to rise by the driving device 109 to reduce the distance between the wafer 200 and the heater 102, until the top of the ejector pin assembly 103 is engaged and embedded in the upper surface of the heater 102 (please refer to Figure 3 ).

[0077] In this embodiment, step 1 of the method for measuring the thermal expansion of the heater is: at a low temperature, the controller controls the heater 102 to descend through the driving device 109, so that the top of the ejector assembly 103 protrudes from the upper surface of the heater 102 and then the heater 102 continues to descend until it reaches the wafer conveying position. At this wafer conveying position, the wafer 200 is conveyed into the reaction chamber and placed on the top of multiple ejector assemblies 103, so that the ejector assemblies 103 jointly support the wafer 200, and at this time, there is a certain distance between the wafer 200 and the heater 102; the controller controls the heater 102 to rise through the driving device 109, shortening the distance between the wafer 200 and the heater 102. During the rising process, the exhaust pipe 105 is kept to exhaust air from between the wafer 200 and the heater 102, and the first air pressure value displayed by the air pressure detection device 107 is recorded in real time. When the first air pressure value tends to be stable, the controller records the first saturation point of the first air pressure value, and obtains the first position of the driving device 109 corresponding to the first air pressure value reaching the first saturation point.

[0078] In step one, as the controller drives the heater 102 to rise through the driving device 109, the distance between the wafer 200 and the heater 102 decreases, the gas that can be sucked between the two becomes less and less, and the indication of the air pressure detection device 107 becomes smaller and smaller; when the indication of the air pressure detection device 107 tends to be stable, it means that there is almost no gas that can be sucked away between the wafer 200 and the heater 102, that is, the distance between the wafer 200 and the heater 102 is zero, and the wafer 200 is adsorbed tightly against the upper surface of the heater 102. At this time, the controller records the first position of the driving device 109 corresponding to the first air pressure value reaching the first saturation point.

[0079] After obtaining the first position, the controller controls the heater 102 to descend through the driving device 109, so that the distance between the heater 102 and the wafer 200 is pulled apart, the ejector assembly 103 supports the wafer 200, and the heater 102 is moved to the wafer transfer position. The robot clamps the wafer 200 from the top of the ejector assembly 103 and transfers it out of the reaction chamber 100.

[0080] In this embodiment, step 2 of the method for measuring the thermal expansion of the heater is: raising the temperature in the reaction chamber 100 to the process temperature and maintaining it, the controller controls the heater 102 to descend to the wafer transfer position through the driving device 109, at which the robot transfers the wafer 200 into the reaction chamber 100 and places it on the top of multiple ejector pin assemblies 103, so that the ejector pin assemblies 103 jointly support the wafer 200; the controller controls the heater 102 to rise through the driving device 109, and during the rising process, the exhaust pipe 105 is kept to exhaust air from between the wafer 200 and the heater 102, and the second air pressure value shown by the air pressure detection device 107 is recorded in real time. When the second air pressure value tends to be stable, the controller obtains the second saturation point of the second air pressure value, and records the second position of the driving device 109 corresponding to the second air pressure value reaching the second saturation point.

[0081] After acquiring the second position, the controller controls the heater 102 to descend through the driving device 109 , so that the ejector assembly 103 protrudes from the upper surface of the heater 102 and supports the wafer 200 until the heater 102 descends to the wafer transfer position, and the robot transfers the wafer 200 out of the reaction chamber 100 .

[0082] It should be noted that when performing the above thermal expansion measurement method, the wafer 200 used is a test wafer, not a process wafer for process reaction. The test wafer does not have upward or downward warping deformation, so as to obtain more accurate process gap data.

[0083] In this embodiment, step three of the method for measuring the thermal expansion of the heater is: the controller calculates the difference between the first position and the second position of the driving device 109 corresponding to the saturation point of the air pressure value at the low temperature and the process temperature, thereby obtaining the vertical thermal expansion of the heater 102 between the low temperature and the process temperature.

[0084] Similarly, in order to obtain more accurate results and eliminate the randomness of the experiment, the above steps 1 to 3 are repeated multiple times to obtain the thermal expansion between multiple low temperatures and process temperatures, and the average value is calculated as the final result.

[0085] The controller is also used to record and store the thermal expansion of the heater 102 between the low temperature and the process temperature. The thermal expansion affects the size of the process gap in the reaction chamber 100. To ensure the consistency of the process gap, during the process, the controller also controls the drive device 109 to compensate for the change in the process gap caused by the thermal expansion.

[0086] This embodiment also provides a thin film vapor deposition system. Figure 1 and Figure 6 As shown, it comprises: a reaction chamber 100, and a gas shower head 101 arranged in the reaction chamber 100, and a heater 102 arranged opposite to the gas shower head 101, the heater 102 is used to carry a wafer 200; a gas extraction pipeline 105 is also arranged in the heater 102, which is used to evacuate the space between the wafer 200 and the heater 102 to a vacuum; a height adjustment component is used to adjust the distance between the wafer 200 and the heater 102. The gas extraction pipeline 105 is used to extract the gas between the heater 102 and the lower surface of the wafer 200, and the first end thereof is connected to the vacuum pump 108, and the second end thereof passes through the back of the heater 102 to between the heater 102 and the wafer 200; an airflow adjustment device 106 and an air pressure detection device 107 are arranged on the gas extraction pipeline 105.

[0087] The second end of the exhaust pipe 105 is connected to the gap between the upper surface of the heater 102 and the lower surface of the wafer 200. Specifically: the surface of the heater 102 is provided with a plurality of bosses and a sealing ring for sealing the upper surface of the heater 102 and the lower surface of the wafer 200, and the bosses, the sealing ring and the gap between the lower surface of the wafer 200 are connected to the exhaust pipe 105; or, in other embodiments, a plurality of grooves are provided on the surface of the heater 102, and the plurality of grooves are connected to the exhaust pipe 105.

[0088] like Figure 6As shown, the height adjustment assembly includes: a plurality of ejector pin assemblies 103 disposed through the heater 102, the ejector pin assemblies 103 being used to support the wafer 200; a driving device 109 for controlling the elevation of the heater 102; wherein, as Figure 3 As shown, the top end of the ejector pin assembly 103 can be snap-fitted and embedded into the upper surface of the heater 102 .

[0089] The thin film vapor deposition system also includes a controller, which controls the heater 102 to rise through the driving device 109, so as to adjust the distance between the wafer 200 and the heater 102 at low temperature and process temperature; the controller is also used to record the indication of the air pressure detection device 107. When the indication of the air pressure detection device 107 tends to be stable, the controller obtains the first position of the driving device 109 corresponding to the first saturation point of the first air pressure value at low temperature and the second position of the driving device 109 corresponding to the second saturation point of the second air pressure value at the process temperature, and calculates the difference between the first position and the second position, so as to obtain the vertical thermal expansion of the heater 102 between the low temperature and the process temperature.

[0090] The controller is further configured to record and store the thermal expansion of the heater 102 between the low temperature and the process temperature, and control the driving device 109 to compensate for the change in the process gap between the lower surface of the gas shower head 101 and the upper surface of the heater 102 caused by the thermal expansion.

[0091] This embodiment also provides a method for measuring a process gap between a gas shower head 101 and a heater 102, comprising the following steps: obtaining a first process gap between the gas shower head 101 and the heater 102 at a low temperature, obtaining the thermal expansion of the heater 102 between the low temperature and the process temperature according to the above-mentioned method for measuring the thermal expansion of the heater 102, calculating the difference between the first process gap and the thermal expansion, and thereby obtaining a second process gap between the gas shower head 101 and the heater 102 at the process temperature.

[0092] Although the content of the present invention has been described in detail through the above optional embodiments, it should be appreciated that the above description should not be considered as a limitation of the present invention. After reading the above content, it will be apparent to those skilled in the art that various modifications and substitutions of the present invention will occur. Therefore, the protection scope of the present invention should be limited by the appended claims.

Claims

1. A thin film vapor deposition system, comprising: a reaction chamber, a gas shower head arranged in the reaction chamber, a heater arranged opposite to the gas shower head, used to carry a wafer; a gas extraction pipeline is also arranged in the heater, a gas pressure detection device is arranged on the gas extraction pipeline, and the gas extraction pipeline is used to suck the gas between the upper surface of the heater and the lower surface of the wafer; a height adjustment component is used to adjust the distance between the wafer and the heater; characterized in that, Also includes: The controller is used to record and store the vertical thermal expansion of the heater between the first temperature and the second temperature, and control the height adjustment component to compensate for the change of the process gap between the lower surface of the gas shower head and the upper surface of the heater caused by the thermal expansion.

2. The thin film vapor deposition system according to claim 1, characterized in that: The controller is also used to perform the following steps: At the first temperature, the distance between the wafer and the heater is gradually reduced by the height adjustment component, and during the process, air is extracted through the exhaust pipe and the first air pressure value of the air pressure detection device is recorded in real time, and the a first position of the height adjustment component corresponding to when the first air pressure value reaches a first saturation point at a first temperature; At the second temperature, the distance between the wafer and the heater is gradually reduced by the height adjustment component, during which air is extracted through the exhaust pipe and the second air pressure value of the air pressure detection device is recorded in real time, and the second position of the height adjustment component corresponding to the second air pressure value reaching the second saturation point at the second temperature is obtained; The difference between the first position and the second position is calculated to obtain the vertical thermal expansion amount of the heater between the first temperature and the second temperature.

3. The thin film vapor deposition system according to claim 1, characterized in that: The surface of the heater is provided with a plurality of bosses and a sealing ring for sealing the upper surface of the heater and the lower surface of the wafer, and the gaps between the bosses, the sealing ring and the lower surface of the wafer are connected to the exhaust pipe.

4. The thin film vapor deposition system according to claim 1, characterized in that: A plurality of grooves are arranged on the surface of the heater, and the plurality of grooves are communicated with the air extraction pipeline.

5. The thin film vapor deposition system according to claim 1, characterized in that: The exhaust pipe is connected to a vacuum pump so that the pressure on the back side of the wafer is lower than the pressure on the front side of the wafer. An airflow regulating device is also arranged on the exhaust pipe.

6. The thin film vapor deposition system according to claim 1, characterized in that: The height adjustment assembly comprises: A driving device for controlling the lifting and lowering of the heater; A plurality of ejector pin assemblies are arranged through the heater, and the ejector pin assemblies are used to support the wafer.

7. The thin film vapor deposition system according to claim 1, characterized in that: The height adjustment assembly comprises: A plurality of ejector pin assemblies are arranged through the heater, and the ejector pin assemblies are used to support the wafer; A driving device controls the simultaneous lifting and lowering of the plurality of ejector pin assemblies.

8. The thin film vapor deposition system according to claim 6 or 7, characterized in that: The driving device is a servo motor, and the stroke position of the servo motor is obtained as the first position and the second position of the height adjustment component.

9. The thin film vapor deposition system according to claim 2, characterized in that: The first temperature is a temperature lower than 80° C., and the second temperature is a process temperature.

10. The thin film vapor deposition system according to claim 2, characterized in that: Repeat this step multiple times and take the average value as the final result.

11. A method for measuring thermal expansion of a heater, wherein the heater is located in a reaction chamber of a thin film vapor deposition system, and the reaction chamber further comprises: An exhaust pipe disposed between the heater and the wafer and communicating with the outside of the reaction chamber is used as a height adjustment component for adjusting the distance between the wafer and the heater, and is characterized by comprising the following steps: At a first temperature, gradually reduce the distance between the wafer and the heater through the height adjustment component, keep the exhaust pipe to exhaust air during the process and record the air pressure value at the outlet of the exhaust pipe in real time, and when the air pressure value tends to be stable, obtain the first position of the height adjustment component corresponding to the first air pressure value reaching the first saturation point at the first temperature; Repeat the above steps at the second temperature, and when the air pressure value at the outlet of the air extraction pipeline tends to be stable, obtain the second position of the height adjustment component corresponding to when the second air pressure value at the second temperature reaches the second saturation point; The difference between the first position and the second position is calculated to obtain the vertical thermal expansion amount of the heater between the first temperature and the second temperature.

12. The method for measuring the thermal expansion of a heater according to claim 11, wherein: The exhaust pipe is connected to a vacuum pump so that the pressure on the back side of the wafer is lower than the pressure on the front side of the wafer. An airflow regulating device is also arranged on the exhaust pipe.

13. The method for measuring the thermal expansion of a heater according to claim 11, wherein: The height adjustment assembly comprises: A driving device for controlling the lifting and lowering of the heater; A plurality of ejector pin assemblies are arranged through the heater, and the ejector pin assemblies are used to support the wafer.

14. The method for measuring the thermal expansion of a heater according to claim 11, wherein: The height adjustment assembly comprises: A plurality of ejector pin assemblies are arranged through the heater, and the ejector pin assemblies are used to support the wafer; A driving device controls the simultaneous lifting and lowering of the plurality of ejector pin assemblies.

15. The method for measuring the thermal expansion of a heater according to claim 13 or 14, characterized in that: The driving device is a servo motor, and the stroke position of the servo motor is obtained as the first position and the second position of the height adjustment component.

16. The method for measuring the thermal expansion of a heater according to claim 11, wherein: The first temperature is a temperature lower than 80° C., and the second temperature is a process temperature.

17. A method for measuring a process gap between a gas shower head and a heater, characterized in that: The method comprises the following steps: obtaining a first process gap between the gas shower head and the heater at a first temperature, obtaining the thermal expansion between the first temperature and the second temperature according to the method for measuring the thermal expansion of the heater as described in any one of claims 10 to 16, calculating the difference between the first process gap and the thermal expansion, and obtaining a second process gap between the gas shower head and the heater at the second temperature.

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