A semiconductor processing apparatus

Abstract

The application discloses a kind of technical problems of semiconductor processing equipment to solve the pressure capacity in the field of semiconductor processing, mainly by a pressure shell to form a closed space, using a pressure regulating device to adjust the air pressure of closed space, and then adjust the air pressure on the surface of semiconductor processing equipment, to optimize the structural design of upper cover.

Description

[0001] This case is a divisional application. Original invention title: Semiconductor processing cavity, semiconductor processing equipment and vapor phase epitaxy equipment Original application number: 2022104103730 Original application date: April 19, 2022 Technical Field

[0002] This invention relates to the field of semiconductor technology, and more particularly to a semiconductor processing apparatus. Background Technology

[0003] Currently, processes such as plasma etching, physical vapor deposition (PVD), and chemical vapor deposition (CVD) are commonly used to microfabricate semiconductor components or substrates, for example, to manufacture flexible displays, flat panel displays, light-emitting diodes, and solar cells. Microfabrication involves various processes and steps, among which chemical vapor deposition is the most widely used. This process can deposit a variety of materials, including a wide range of insulating materials, most metals, and metal alloys. This process is generally carried out in a high-vacuum reaction chamber.

[0004] With the continuous miniaturization of semiconductor device features and the increasing integration of devices, higher and higher requirements are being placed on the uniformity of thin films deposited by chemical vapor deposition. Although chemical vapor deposition equipment has undergone several upgrades and its performance has been greatly improved, there are still many shortcomings in terms of thin film deposition uniformity. In particular, with the increasing size of substrates, existing vapor deposition methods and equipment are no longer able to meet the uniformity requirements of thin films.

[0005] During thin film deposition, various process conditions affect the uniformity of film deposition on the substrate surface, such as the direction and distribution of reactive gas flow, the heating temperature field of the substrate, and the pressure distribution within the reaction chamber. If the process environment within the reaction zone is not entirely consistent, it can lead to defects such as uneven thickness, uneven composition, and uneven physical properties in the deposited film on the substrate surface, thereby reducing the yield of substrate production. Therefore, existing chemical vapor deposition equipment needs to be improved to enhance the uniformity of substrate film deposition. Furthermore, for the epitaxial growth process of silicon or silicon-germanium materials, since these epitaxial materials are typically the bottom layer of semiconductor devices, with extremely small critical dimensions (CD), usually only a few nanometers, and cannot withstand prolonged high temperatures (otherwise, it will damage the semiconductor device), it is necessary to heat the substrate to a temperature sufficient for silicon epitaxial growth, such as 600-700 degrees Celsius, within a very short time. Due to this stringent temperature requirement, silicon epitaxial processes typically use high-power heating lamps to heat the substrate within a transparent quartz reaction chamber. Because the pressure inside the reaction chamber is much lower than the atmospheric pressure outside the quartz reaction chamber, a pressure-resistant structure needs to be designed on the chamber to prevent deformation or breakage due to the huge pressure difference. For example, multiple reinforcing ribs can be placed around the flat upper and lower quartz chamber walls, or the upper and lower quartz chamber walls can be designed in a dome shape to resist atmospheric pressure. These quartz outer walls typically have a wall thickness of 6-8 mm to resist atmospheric pressure while allowing as much radiant energy as possible to penetrate into the reaction chamber. These two structural designs are opposite in direction, and their technical effects cannot coexist. They each have advantages and disadvantages in terms of their impact on substrate processing. The flat chamber ensures a stable distribution of airflow throughout the chamber, but the numerous reinforcing ribs (more than 10) at the top can block the heating radiation, leading to uneven temperature distribution. The dome-shaped reaction chamber provides a more uniform temperature distribution, but the airflow generates a large amount of turbulent flow when entering the dome-shaped reaction area, making airflow distribution difficult to control. Summary of the Invention

[0006] To address the aforementioned technical problems, the present invention aims to provide a semiconductor processing apparatus for processing substrates that can achieve both good radiation transmittance and consistent temperature distribution, as well as uniform and stable airflow distribution.

[0007] This invention provides a semiconductor processing apparatus for processing a substrate, comprising: A chamber frame having a sealed processing space inside for performing processing on the substrate; The air pressure in the processing space can be adjusted according to the processing conditions; A pressure-bearing housing that at least surrounds a portion of the chamber frame, wherein the inner side of the pressure-bearing housing and the outer side of the chamber frame form a sealed space; and, A pressure regulating device is used to regulate the pressure of the enclosed space.

[0008] Optionally, the pressure-bearing housing at least surrounds the upper central region of the chamber frame; and / or the pressure-bearing housing at least surrounds the lower central region of the chamber frame; or the pressure-bearing housing completely surrounds the outer side of the chamber frame.

[0009] Optionally, the chamber frame includes a chamber sidewall, a chamber topwall, and a chamber bottomwall.

[0010] Optionally, the pressure-bearing housing covers the sidewalls of the chamber, and / or the upper wall of the chamber, and / or the bottom wall of the chamber.

[0011] Optionally, the pressure-bearing housing is airtightly connected to the outer wall of the chamber frame via fasteners.

[0012] Optionally, the pressure regulating device includes a vacuum pump, and the pressure-bearing housing includes an air extraction port connected to the vacuum pump.

[0013] Optionally, the voltage regulating device includes: A monitoring module is used to measure the air pressure value of the processing space and / or the enclosed space; The control module is used to preset a safety pressure difference and adjust the pressure of the processing space and the sealed space according to the safety pressure difference based on the pressure value.

[0014] Optionally, the pressure-bearing housing includes a heat exchange system.

[0015] Optionally, the heat exchange system includes a helium source that is introduced into the enclosed space.

[0016] Optionally, the chamber frame and / or the pressure-bearing shell are made of metal.

[0017] Optionally, the pressure regulating device is used to adjust the pressure of the sealed space to be less than 1 standard atmosphere during the process.

[0018] Optionally, the pressure regulating device is used to adjust the pressure of the sealed space to less than 0.5 standard atmospheres during the process.

[0019] Optionally, the pressure regulating device is used to adjust the pressure in the sealed space to be greater than or equal to the pressure in the processing space during the process. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1A , Figure 1B and Figure 1C This is a schematic diagram of the structure of a semiconductor processing device according to the present invention. Figure 1A yes Figure 1B A schematic diagram of the cross-sectional structure along the vertical direction. Figure 1C for Figure 1B Exploded view; Figure 1D This is a schematic diagram of another semiconductor processing device structure according to the present invention; Figure 2A and Figure 2B This is a schematic diagram of the structure of the top cover of the present invention. Figure 2B for Figure 2A Schematic diagram of the cross-sectional structure along line AA; Figure 3A and Figure 3B This is a schematic diagram of another type of top cover according to the present invention. Figure 3B for Figure 3A Schematic diagram of the cross-sectional structure along line BB; Figure 4A and Figure 4B This is a schematic diagram of another type of top cover of the present invention. Figure 4B for Figure 4A A schematic diagram of the cross-sectional structure along line CC; Figure 5A and Figure 5B This is a schematic diagram of another type of top cover according to the present invention. Figure 5B for Figure 5A Schematic diagram of the cross-sectional structure along line DD; Figure 6A , Figure 6B and Figure 6C This is a schematic diagram of another type of top cover according to the present invention. Figure 6B for Figure 6A Schematic diagram of the cross-sectional structure along line EE. Figure 6C for Figure 6A Schematic diagram of the cross-sectional structure along line FF; Figure 7A and Figure 7B This is a schematic diagram of another type of top cover according to the present invention. Figure 7B for Figure 7A Schematic diagram of the cross-sectional structure along line GG; Figure 8A and Figure 8BThis is a schematic diagram of another type of top cover according to the present invention. Figure 8B for Figure 8A A schematic diagram of the cross-sectional structure along line HH; Figure 9 This is a schematic diagram of the structure of a semiconductor processing device according to the present invention; Figure 10 This is a schematic diagram showing the connection between the upper cover and the chamber frame in another embodiment of the present invention; Figure 11 This is a schematic diagram of an epitaxial device structure according to the present invention. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] This invention addresses the technical problem of incompatibility between the advantages of two existing technical solutions. It proposes an ingenious solution that overcomes the shortcomings of existing technologies, takes into account the advantages of existing technical solutions, and is simple in design. It can ensure high infrared transmittance, achieve uniform and flat airflow distribution, and reduce the cost of use.

[0024] This invention provides a semiconductor processing apparatus applicable to substrate processing in semiconductor equipment such as chemical vapor deposition (CVD), atomic layer deposition (ALD), plasma-enhanced vapor deposition (PEVD), and physical vapor deposition (PVD). Specifically, a substrate is placed in the processing space inside a hollow chamber frame. An infrared-transmitting top cover is assembled on the chamber frame for heating the substrate. A pressure-bearing shell at least partially covers the infrared transmission area of ​​the top cover, forming an airtight sealed space. A pressure regulating device adjusts the air pressure within the sealed space, allowing the pressure difference between the upper and lower surfaces of the top cover to be adjustable. This achieves a flatter top cover structure design with higher infrared transmittance and sufficient mechanical strength under a smaller pressure difference, meeting increasingly demanding process requirements.

[0025] The present invention further provides a top cover for a semiconductor processing device, wherein the top cover forms a processing space with the semiconductor processing device, and forms a sealed space with a pressure-bearing housing. The top cover is disposed between the processing space and the sealed space to achieve airtight isolation between the two. The top cover has a lower surface facing the processing space and an upper surface facing the sealed space. Specifically, the top cover includes a window located in the middle of the top cover and an outer edge surrounding the window. The window is heat-radiation-transmitting. The window includes a central window area located at its center and a window edge area surrounding the central window area. The window edge area is connected to the outer edge. The height difference between the lower surface of the central window area and the lower surface of the window edge area is less than or equal to 28 mm. The top cover can withstand the pressure difference between the processing space and the sealed space. The top cover can ensure a stable distribution of airflow throughout the cavity, withstand the pressure difference between its upper and lower surfaces, and has high infrared transmittance.

[0026] Based on the above inventive concept, there are various implementation methods and variations, which are described in detail below with reference to the accompanying drawings: Figure 1A , Figure 1B and Figure 1C This is a schematic diagram of the structure of a semiconductor processing device according to the present invention. Figure 1A yes Figure 1B A schematic diagram of the cross-sectional structure along the vertical direction. Figure 1C for Figure 1B Exploded view.

[0027] like Figure 1A-1C The diagram shown is a side view of a semiconductor processing device according to the present invention, including a chamber frame 110. In some embodiments, it can be a hollow disc-shaped frame or a hollow cuboid frame, and can be integrally formed or assembled from multiple parts. An air inlet 111 and an air outlet 112 are provided on opposite sides of the chamber frame. Process gas is introduced into the air inlet 111 through an external gas source, and a vacuum pump can be connected to the air outlet to extract the process gas. In some embodiments, the air inlet 111 and the air outlet 112 are as follows: Figure 1A As shown, the chamber frame 110 is positioned on two opposite sides of the rectangular chamber frame 110; in other embodiments, it may be positioned in other locations. The chamber frame 110 may be made of metal to provide sufficient mechanical strength.

[0028] An upper cover 120 and a lower cover 130 are provided on opposite sides of the chamber frame 110. In this embodiment, the upper and lower surfaces of the rectangular chamber frame 110 have openings corresponding to the size of the upper cover 120 and the lower cover 130. The shape and size of the openings can be adjusted according to the different shapes of the upper cover 120 and the lower cover 130. After the upper cover 120, the lower cover 130 and the chamber frame 110 are assembled together, a processing space 140 can be formed inside the chamber frame 110. The substrate W to be processed can be placed in the processing space 140. The lower surface of the upper cover 120 is located in the processing space. The air inlet 111 and the air outlet 112 are connected to the processing space 140 so that the process gas can flow in the processing space 140. The upper cover 120 can transmit infrared thermal radiation. In some embodiments, the upper cover 120 is at least partially made of a transparent material, such as transparent quartz. In other embodiments, the lower cover 130 is made of the same material as the upper cover 120. The device emitting thermal radiation is located on the outside of the upper cover, allowing the thermal radiation to irradiate the substrate W in the processing space 140 to perform the chemical vapor deposition process. In other embodiments, the outer side of the lower cover 130 is also provided with a device emitting thermal radiation. In other embodiments, the thermal radiation device on the outside of the lower cover 130 may be omitted, and the substrate W may be irradiated by infrared radiation transmitted through the upper cover 120 to produce the deposition reaction.

[0029] In other embodiments, the chamber frame 110 and the cover 120 may also be an integral structure, with the cover 120 having higher infrared radiation transmittance and the chamber frame 110 having higher mechanical strength and lower infrared transmittance.

[0030] like Figure 1A As shown, a pressure-bearing shell 150 is provided on the outside of the chamber frame 110. The shell can be made of metal and is a hollow structure with openings. The edge of the opening of the pressure-bearing shell 150 is airtightly connected to the outside of the chamber frame 110 by fasteners. At least part of the upper surface of the chamber frame 110 is included inside the hollow structure. The fasteners can be fastening screws. In this embodiment, the pressure-bearing shell 150 is airtightly connected to the upper surface of the chamber frame 110 and forms a closed space 160 with the upper surface of the cover 120 and part of the upper surface of the chamber frame 110. The upper surface of the cover 120 is wrapped with the minimum volume of the pressure-bearing shell. The upper surface of the cover 120 is located in the closed space 160. In other embodiments, the pressure-bearing shell 150 can also be airtightly connected to the side wall or bottom wall of the chamber frame 110.

[0031] like Figure 1D The diagram shown is a schematic diagram of another semiconductor processing device structure according to the present invention. Figure 1AThe difference in the embodiment shown is that the pressure-bearing housing 150 is connected to the edge of the upper cover 120. The specific connection method can be to achieve an airtight connection through an assembly ring or connecting parts, etc. The sealed space 160 is formed by the pressure-bearing housing 150 and a part of the upper cover.

[0032] The pressure-bearing housing 150 is connected to the edge of the upper cover 120. This connection is suitable when the pressure difference between the sealed space 160 formed by the pressure-bearing housing 150 and the upper cover 120 and the external atmospheric environment is small. In this case, the pressure on the pressure-bearing housing 150 is relatively small, resulting in less pressure on the edge of the upper cover 120, making it less likely for the edge of the upper cover 120 to be crushed by the pressure-bearing housing 150. When the pressure difference between the sealed space 160 and the external atmospheric environment is large, the pressure-bearing housing 150 cannot be directly placed on the edge of the upper cover 120. A transition ring (not shown in the figure) is provided between the edge of the pressure-bearing housing 150 and the edge of the upper cover 120. This transition ring extends from the edge of the window 120 to the top of the chamber frame 110, primarily bearing pressure through the chamber frame 110. The pressure on the edge of the window 120 is relatively small, making it less likely for the edge of the window 120 to break.

[0033] During the process, in order to perform the deposition reaction in the processing space 140, the processing space 140 needs to be depressurized. At this time, there will be a relatively large pressure difference between the lower surface of the upper cover 120 in the processing space 140 and the upper surface of the upper cover 120 in the sealed space 160. Typically, the environment on the lower surface of the upper cover 120 is close to a vacuum, while the pressure on the upper surface of the upper cover 120 is close to atmospheric pressure. Therefore, the upper cover needs to have sufficient mechanical strength to withstand the pressure. Existing technology can improve the mechanical strength by increasing the thickness of the upper cover 120, but this will reduce the transmittance of infrared radiation, resulting in wasted power. Alternatively, dense reinforcing ribs can be set on the outside of the upper cover 120, but this will block infrared radiation. The locations with and without reinforcing ribs will produce radiation differences on the substrate, resulting in uneven deposition. Or, the upper cover 120 can be made into a structure with a large arc, but this will cause a large change in the airflow distribution in the processing space 140, resulting in uneven airflow and also leading to uneven deposition. Therefore, the present invention connects a pressure regulating device 170 to the outside of the pressure-bearing housing 150 (please refer to...). Figure 1AThis device is used to reduce the pressure difference between the upper and lower surfaces of the cover 120 during the manufacturing process by adjusting the air pressure in the sealed space 160. This allows the cover 120 to be made of thinner quartz, and even if the side of the cover 120 facing the substrate W is made flat, it will not be damaged by the internal and external pressure difference. In this embodiment, the sealed space 160 formed by the pressure-bearing housing 150 surrounds the upper surface of the cover 120 corresponding to the substrate, and a pressure regulating device 170 reduces the air pressure in the sealed space 160 during the manufacturing process. This reduces the pressure difference between the upper surface of the cover 120 and the sealed space, which is at atmospheric pressure during the manufacturing process. This makes the shape and structure of the cover 120 more flexible and can be adjusted according to the strict requirements of the manufacturing process, thereby improving the processing quality of the substrate W.

[0034] In some embodiments, the pressure regulating device 170 may include a vacuum pump, with a sealing tube on the pressure-bearing housing 150 connecting the sealed space 160 to the vacuum pump, adjusting the air pressure within the sealed space 160 based on feedback from a barometer. In some embodiments, during the process, because the side of the substrate W to be processed is mainly heated by infrared radiation transmitted through the upper cover 120, and the process airflow mainly flows on the side of the substrate W to be processed, the shape and thickness requirements of the lower cover 130 are not high. That is, the lower cover 130 can be made to have its upper surface exposed to the atmosphere by increasing its mechanical strength through thickening, a larger arch, or reinforcing ribs. By adjusting the air pressure in the sealed space 160, the air pressure on the upper surface of the upper cover 120 during the process is made greater than or equal to the air pressure in the processing space 140, and less than the air pressure on the lower surface of the lower cover 130. For example, the air pressure in the sealed space 160 is 0.5 atmospheres, and the air pressure in the processing space is close to a vacuum. The lower surface of the lower cover 130 is subjected to one atmosphere of pressure. With this design, when the processing space is evacuated to a near-vacuum state during the process, the upper cover with a thinner and flatter surface used in this invention has sufficient bonding force at the molecular level to withstand the tension generated by the different air pressures on the upper and lower surfaces, preventing it from breaking during operation. The thinner upper cover 120 also results in higher infrared radiation transmittance. Under the condition that the substrate W obtains the same amount of radiation, the radiation source can consume less power. At the same time, the flatter surface makes the flow of process gas in the processing space smoother and more stable, without generating local eddies, and thus will not affect the stability of local gaseous reactants on the substrate W. Therefore, the uniformity of film formation on the substrate W at different locations can be obtained. Furthermore, because the upper surface of the substrate W requires high uniformity in heat radiation and airflow, while the lower surface primarily transfers heat through the base, and the base supporting the substrate needs to connect to the support frame, the transmission mechanism penetrating the lower cover, and the power mechanism located outside the processing chamber, the lower cover has lower requirements in terms of thickness and shape. This means that extensive modifications to the lower part of the processing chamber are unnecessary; simply combining the pressure-bearing housing 150 with the chamber frame is sufficient to achieve the desired technical effect. Preferably, the optimized design of the upper cover is achieved by combining the pressure-bearing housing 150 with the upper surface of the chamber frame 110. Moreover, maintaining a certain air pressure within the sealed space 160 improves the heat exchange efficiency of the gas flow within it. In a vacuum environment, the low gas content hinders heat transfer from the upper cover 120, making accurate temperature control of the upper cover 120 impossible.

[0035] In other embodiments, the pressure regulating device 170 includes a monitoring module, specifically a barometer located in the sealed space 160 and the processing space 140, for real-time feedback of the ambient air pressure signal. It also includes a control module, which can set an initial safe pressure difference between the sealed space 160 and the processing space 140, such as 0.5 standard atmospheres or 0 standard atmospheres. Under this safe pressure difference, the cover of a certain thickness used in this invention can work safely. When the air pressure signal fed back by the monitoring module differs from the initially set safe pressure difference value after calculation, the control module can also dynamically adjust it to maintain the pressure difference between the upper and lower surfaces of the cover 120 at a preset value.

[0036] Figure 2A and Figure 2B This is a schematic diagram of the structure of a top cover according to the present invention, wherein... Figure 2B yes Figure 2A A cross-sectional view along line AA.

[0037] Please refer to Figure 2A and 2B The upper cover 120 includes a window 221 region located in its middle and an outer edge 222 region surrounding the window 221. The upper surfaces of the window 221 and the outer edge 222 are not necessarily on the same plane. For example, in this embodiment, the window 221 is circular and the outer edge 222 is annular. Figure 2B The middle part is lower than the outer edge 222. The window 221 and the outer edge 222 are connected by a vertical surface. In fact, the connection between the window 221 and the outer edge 222 is not necessarily a vertical surface. For example, it can be an inclined surface, or even an arc surface. It is not limited here.

[0038] The height difference between the lower surface of window 221 and the lower surface of outer edge 222 depends on the structure of chamber frame 110, with outer edge 222 supported by chamber frame 110 (see [link]). Figure 1A , 1B and Figure 1C The upper cover 120 and the chamber frame 110 are used to achieve a seal between the upper cover 120 and the chamber frame 110. The surface of the upper cover 120 facing the processing space 140 is defined as the lower surface, and the surface of the upper cover 120 facing the sealed space 160 is defined as the upper surface. In this embodiment, both the lower and upper surfaces of the outer edge 222 are planes, which is beneficial for pressing and sealing the lower surface of the outer edge 222 with the chamber frame 110, and for achieving a seal between the upper surface of the outer edge 222 and the pressure-bearing housing 150.

[0039] The window 221 is used to transmit the infrared radiation required by the substrate W. Since the lower surface of the window 221 is at approximately the same height as the top of the air inlet 111, the process gas flow enters the reaction chamber from the air inlet and flows horizontally across the lower surface of the window 221 until it reaches the air outlet. During this process, the process gas flow is close to horizontal, which is beneficial to the uniformity of the film layer on the surface of the substrate W.

[0040] In addition, the thinner the window 221, the less infrared radiation is lost when passing through the window 221. Furthermore, the lower surface of the window 221 is recessed away from the lower surface of the outer edge 222, meaning that the distance between the lower surface of the window 221 and the surface of the substrate W is shorter. This results in less infrared radiation loss during the process of infrared radiation passing through the window 221 to reach the substrate. Consequently, more infrared radiation reaches the surface of the substrate W, which is beneficial for better heating of the surface of the substrate W.

[0041] This invention reduces the pressure difference between the upper and lower surfaces of the cover 120 by providing a pressure-adjustable sealed space 160 above the cover 120 and adjusting the pressure within the sealed space 160 to be less than standard atmospheric pressure during the process. This allows the window 221 of the cover 120 to have a smaller thickness and higher flatness, effectively improving the window's high transmittance and the airflow stability within the processing chamber, while preventing damage to the window 221 due to pressure differences. In some embodiments, the window 221 is made of transparent quartz, and the outer edge 222 is made of opaque quartz. This protects the sealing strip from direct infrared radiation, improving its lifespan. In other embodiments, the outer edge 222 can also be made of transparent quartz. In other embodiments, the window 221 and the outer edge 222 can also be non-planar structures, subject to flexible adjustments based on actual process requirements.

[0042] In this embodiment, the window 221 is circular, and the area of ​​the window 221 is larger than the area of ​​the substrate W. For example, if the diameter of the substrate W is 300 mm, the diameter of the window 221 can be in the range of 400 mm to 470 mm. This allows the substrate W and some components on its edge to be heated, preventing the problem of heat loss from the surface of the substrate W through the edge components when only the substrate W is heated. However, the horizontal dimension of the window 221 should not be too large, so that the window 221 can not only meet the heating requirements, but also prevent the volume of the reaction chamber from becoming too large.

[0043] In this embodiment, the window 221 includes a window center area M located at its center and a window edge area N surrounding the window center area M, and the edge area N is connected to the outer edge 222. The height difference between the window center area M and the window edge area N is zero, which makes the process airflow from the window edge area N to the window center area M and then back to the window edge area N more stable, which is beneficial to improving the uniformity of the thin film formed on the surface of the substrate W.

[0044] In other embodiments, the height difference between the window center area M and the window edge area N is greater than 0 mm and less than or equal to 28 mm.

[0045] Figure 3A and Figure 3B This is a schematic diagram of another type of top cover of the present invention, wherein... Figure 3B yes Figure 3A A cross-sectional view along line BB.

[0046] Figure 3A and Figure 3B The illustrated top cover embodiment and Figure 2A and Figure 2B The differences in the illustrated embodiment include: a reinforcing rib 323 is provided on the upper surface of the window 221. In this embodiment, the reinforcing rib 323 is a complete ring structure, and the complete ring-shaped reinforcing rib 323 is a single circle. In fact, the ring-shaped reinforcing rib 323 can also be provided in multiple circles, and each circle of the ring-shaped reinforcing rib 323 can be a continuous ring structure, or each circle of the reinforcing rib 323 can be several arc segments, and these several arc segments form a ring structure. In order to prevent the reinforcing rib 323 from blocking infrared radiation, the reinforcing rib 323 may not be provided in the area of ​​the window 221 directly opposite the substrate W.

[0047] In this embodiment, the principle by which the reinforcing rib 323 can improve the mechanical strength of the upper cover 120 includes: from a microscopic perspective, the window 221 includes several interconnected window units. When the reinforcing rib 323 is added, the window unit is not only connected to other surrounding window units, but also to the reinforcing rib 323. This makes the window 221 have a greater load-bearing capacity when subjected to pressure differences between the upper and lower surfaces compared to a window unit that is only connected to surrounding window units. Therefore, setting the reinforcing rib 323 is beneficial to improving the pressure-bearing capacity of the upper cover 120, which can further reduce the thickness of the window 221. This can prevent the upper cover from breaking and also improve the ability of the upper cover 120 to transmit heat radiation.

[0048] In this embodiment, multiple gas channels 324 are evenly arranged on the reinforcing rib 323. The reinforcing rib 323 and the outer edge 222 form an edge region, and the interior of the annular reinforcing rib 323 forms a central region. Here, the central region is not the aforementioned window center region M, and the edge region is not the aforementioned window edge region N. The gas channels 324 are used to connect the central region and the edge region, which helps to improve the contact between the cooling airflow and the window 221 and maintain the overall temperature control accuracy of the upper cover 120. The gas channels 324 can be through holes, air grooves, or openings. The number and position of the gas channels 324 should be chosen to balance the strength improvement effect of the reinforcing rib 323 and the cooling gas flow effect.

[0049] In this embodiment, the window 221 includes a window center area M located at its center and a window edge area N surrounding the window center area M, and the edge area N is connected to the outer edge 222. The height difference between the window center area M and the window edge area N is zero, which makes the process airflow from the window edge area N to the window center area M and then back to the window edge area N more stable, which is beneficial to improving the uniformity of the thin film formed on the surface of the substrate W.

[0050] In other embodiments, the height difference between the window center area M and the window edge area N is greater than 0 mm and less than or equal to 28 mm.

[0051] Figure 4A and Figure 4B This is a schematic diagram of another type of upper cover of the present invention, wherein... Figure 4B yes Figure 4A A cross-sectional view along line CC.

[0052] Please refer to Figure 4A and 4B ,and Figure 2A and Figure 2B The differences in the illustrated embodiment include that the window 221 is a rectangular plane and the outer edge 222 is a rectangular ring. Along the airflow direction from the air inlet to the air outlet, the upper cover 120 of this embodiment has a longer window 221, which is beneficial for the airflow to have more time to form laminar flow before reaching the substrate W.

[0053] In this embodiment, the window 221 is rectangular, requiring the area of ​​the inscribed circle of the rectangle to be larger than the area of ​​the substrate W. The rectangular window includes a long side and a short side. The short side has a size of 400 mm to 470 mm, and the long side has a size of 400 mm to 650 mm. This ensures that both the substrate W and the components at its edges are heated, preventing heat loss from the substrate W through its edges. This results in better temperature uniformity on the substrate W surface, which is beneficial for forming a thin film on the substrate W surface. Furthermore, this ratio of long to short sides improves airflow stability and makes the substrate W temperature easier to control.

[0054] Figure 5A and Figure 5B This is a schematic diagram of another type of upper cover of the present invention, wherein... Figure 5B yes Figure 5A A cross-sectional view along line DD.

[0055] Please refer to Figure 5A and Figure 5B ,and Figure 4A and Figure 4B The differences in the embodiments include: A strip-shaped reinforcing rib 523 perpendicular to the airflow direction X is provided near the air outlet and air inlet of the window 221 to improve the mechanical strength of the window 221. The substrate W is placed below the center of the window 221, slightly off-center from the air inlet. Correspondingly, the number of reinforcing ribs 523 at the air inlet is less than the number at the air outlet. No reinforcing ribs 523 are provided at the position of the window 221 directly opposite the substrate W to avoid blocking infrared radiation.

[0056] In this embodiment, the principle by which the reinforcing rib 523 can improve the mechanical strength of the upper cover 120 includes: from a microscopic perspective, the window 221 includes several interconnected window units. When the reinforcing rib 523 is added, the window unit is not only connected to other surrounding window units, but also to the reinforcing rib 523. This makes the window 221 have a greater load-bearing capacity when subjected to pressure differences between the upper and lower surfaces compared to a window unit that is only connected to surrounding window units. Therefore, setting the reinforcing rib 523 is beneficial to improving the pressure-bearing capacity of the upper cover 120, which can further reduce the mechanical strength of the window 221. This can prevent the upper cover from breaking and also improve the ability of the upper cover 120 to transmit heat radiation.

[0057] In this embodiment, the window 221 includes a window center area M located at its center and a window edge area N surrounding the window center area M, and the edge area N is connected to the outer edge 222. The height difference between the window center area M and the window edge area N is zero, which makes the process airflow from the window edge area N to the window center area M and then back to the window edge area N more stable, which is beneficial to improving the uniformity of the thin film formed on the surface of the substrate W.

[0058] In other embodiments, the height difference between the window center area M and the window edge area N is greater than 0 mm and less than or equal to 28 mm.

[0059] Figure 6A , 6B and Figure 6C This is a schematic diagram of another upper cover structure of the present invention, wherein, Figure 6B This is a schematic diagram of the cross-sectional structure along line EE. Figure 6C This is a schematic diagram of the cross-sectional structure along line FF.

[0060] please Figure 6A 6B and Figure 6C The plane containing the lower surface of the window 221 is higher than the plane containing the lower surface of the outer edge 222, giving the entire upper cover 120 an upward arched shape while maintaining the window 221 as a planar structure. Figure 6C The diagram shows a cross-sectional view of the upper cover 120 in this embodiment along line FF perpendicular to the airflow direction. The inner side of the outer edge 222 is connected to the window 221 via a second inclined surface 626 of a connecting portion. This allows the process gas to slow down the abrupt upward rise when entering the processing space from the inlet, preventing turbulence at that point. In the cross-sectional view along the airflow direction EE shown in diagram 6B, the inner side of the outer edge has a first inclined surface 625 near the connection with the window. This first inclined surface 625 below the connection between the window 221 and the outer edge 222 not only optimizes airflow regulation in this embodiment but also ensures that the lower surface of the outer edge 222 is on the same plane, which is more conducive to the sealing of the upper cover 120 and the chamber frame 110. An undulating plane would place higher demands on the selection of the sealing strip, while a flat plane is easier to achieve a consistent sealing strength. Additionally, in this embodiment, a strip-shaped reinforcing rib 323 connecting the window 221 and the outer edge 222 can be provided on the upper surface of the upper cover 120 to improve its mechanical strength.

[0061] In this embodiment, the window 221 includes a window center area M located at its center and a window edge area N surrounding the window center area M, and the edge area N is connected to the outer edge 222. The height difference between the window center area M and the window edge area N is zero, which makes the process airflow from the window edge area N to the window center area M and then back to the window edge area N more stable, which is beneficial to improving the uniformity of the thin film formed on the surface of the substrate W.

[0062] In other embodiments, the height difference between the window center area M and the window edge area N is greater than 0 mm and less than or equal to 28 mm.

[0063] Figure 7A and Figure 7B This is a schematic diagram of another type of top cover according to the present invention. Figure 7B for Figure 7A A schematic diagram of the cross-sectional structure along line GG.

[0064] In this embodiment, the outer edge 222 is annular, and the lower surface of the window 221 protrudes towards the enclosed space relative to the lower surface of the outer edge 222; that is, the window 221 is arched. When the window 221 is arched, according to force analysis, the external gas pressure borne by the chamber is decomposed into a force along the tangential direction of the window 221 and a force perpendicular to the tangential direction of the window 221. When the window 221 is planar, it needs to bear the sum of these two forces. However, with the window 221 set as an arched structure, the window only needs to bear the force perpendicular to the tangential direction of the window 221. Therefore, the arched window 221 can be made thinner than a flat window to withstand the pressure difference between the inside and outside of the window 221. At the same time, due to the thinner thickness of the window 221, the infrared thermal radiation transmission efficiency of the window 221 is very high, which is more conducive to the control of the substrate temperature.

[0065] Specifically, the thickness of the window 221 ranges from 4 mm to 12 mm. In reality, the thickness of the window 221 is affected by the pressure difference between the inside and outside of the window 221 and the arch height of the arched structure of the window 221. The arch height refers to the height difference between the lower surface of the central area M of the window and the edge area N of the window. When the arch height of the arched structure of the window 221 remains unchanged, reducing the pressure difference between the inside and outside of the window 221 can make the window 221 thinner. Of course, keeping the pressure difference between the inside and outside of the window 221 constant, increasing the arch height of the window 221 can also make the window 221 thinner. However, an excessively high arch height is not conducive to the stability of airflow. According to the process requirements, the arch height of the window 221, the pressure difference between the inside and outside of the window 221, and the thickness of the window 221 can be comprehensively adjusted to meet the requirements of airflow stability, pressure resistance, and heat permeability.

[0066] In this embodiment, the thickness of the window 221 ranges from 4 mm to 12 mm. When the pressure difference between the inside and outside of the window 221 is 0.2 to 0.8 atmospheres, the height difference between the central area M and the edge area N of the window is greater than 0 mm and less than or equal to 25 mm. That is, the height difference between the central area M and the edge area N of the window is small, so that after the process airflow enters the reaction chamber from the air inlet, it flows from the edge area N to the central area M and then back to the edge area N. The airflow is relatively smooth and does not float too much upward, making the overall process airflow stable, which is beneficial to improving the uniformity of the film formed on the surface of the substrate W.

[0067] In summary, the arched structure of the window 221 has good pressure resistance and can be made thinner, with good infrared heat radiation transmission capability. Furthermore, the arch height of the arched structure is not too large, which helps to ensure the stability of airflow and improve the uniformity of the film formed on the substrate surface.

[0068] Figure 8Aand Figure 8B This is a schematic diagram of another type of top cover according to the present invention. Figure 8B for Figure 8A A schematic diagram of the cross-sectional structure along line HH.

[0069] Please refer to Figure 8A and Figure 8B In this embodiment, the outer edge 222 is annular, and the window 221 includes a window center area M and a window edge area N. The window center area M is a flat plate structure, and the centerline of the window center area M is located between the lower surface and the upper surface of the outer edge 222. That is, the upper surface of the window center area M is lower than the upper surface of the outer edge 222, and the lower surface of the window center area M is higher than the lower surface of the outer edge 222. The outer edge 222 and the window center area M are connected through the window edge area N with an arc surface. The height difference between the edge area N and the window center area M is less than or equal to 28 mm, which makes the process airflow from the window edge area N to the window center area M and back to the window edge area N more stable, which is beneficial to improving the uniformity of the thin film formed on the surface of the substrate W.

[0070] The top cover of the present invention is suitable for devices that need to withstand different pressure environments on the upper and lower surfaces of the top cover. The type of device is not limited here, but is described in detail below with the example of a semiconductor processing device for which the top cover is applicable: like Figure 9This is a schematic diagram of a semiconductor processing device according to the present invention. It includes a metal chamber frame 110, providing a foundation for assembling other components of the entire semiconductor device. An air inlet 111 and an air outlet 112 are arranged opposite each other on the lateral sides of the chamber frame 110 for introducing process gases. An upper cover 120 and a lower cover 130, which are permeable to heat radiation, are arranged opposite each other on the upper and lower sides of the chamber frame 110. A corresponding opening 915 is provided on the upper surface of the chamber frame 110, into which the upper cover 120 can be embedded and airtightly connected to the chamber frame 110 via a sealing strip 919. The chamber frame 110, upper cover 120, and lower cover 130 form a processing space 140. It also includes a base 990 located within the processing space 140, whose upper surface supports a substrate W, and whose lower surface is supported by a bracket. The surface of the substrate W to be processed faces the upper cover 120. The frame can drive the base 990 to rotate. On one side of the chamber frame 110, in a direction perpendicular to the air inlet direction and lower than the plane where the air inlet and outlet are located, there is a transfer port 916. The transfer port 916 can also be located in other positions. When it is necessary to transfer the substrate W before or after the process reaction, the frame can drive the base down to the transfer port 916 position to facilitate the picking and dropping of the substrate W. There is also a metal pressure-bearing shell 150, which is airtightly connected to the chamber frame 110 and forms a closed space 160 with the top cover 120 and the chamber frame 110. A pressure regulating device 170 is used to reduce the pressure difference between the upper surface and the lower surface of the top cover 120 relative to the closed space 160 when it is at normal pressure during the process by adjusting the air pressure of the closed space 160, so that the shape and structure of the top cover 120 are more conducive to the transmission of infrared radiation and the uniform flow of air. In other embodiments, the semiconductor device further includes a heating lamp assembly 980 located in the enclosed space 160 at a certain distance from the upper cover 120. The heating lamp assembly 980 emits infrared radiation that passes through the upper cover 120 to heat the substrate W, causing it to undergo a chemical deposition reaction in the process gas environment. Simultaneously, a heating lamp can also be disposed on the outside of the lower cover 130, emitting infrared radiation that passes through the lower cover 130 to heat the base 990, assisting the film formation reaction on the surface of the substrate W. In other embodiments, the semiconductor device of the present invention further includes an inlet flange 913 and an outlet flange 914, both internally equipped with gas pipelines that can be connected to an external gas source to modulate the process gas, making the deposition reaction in the processing space 140 more uniform. In some embodiments, the upper cover 120 strengthens the airtightness of the sealing strip 919 between the upper cover 120 and the chamber frame 110 through a clamping ring 921.

[0071] In the semiconductor processing apparatus disclosed in this invention, the upper cover 120 includes a transparent quartz window located in the center of the upper cover and an opaque quartz outer edge surrounding the window. The window can be circular or rectangular in shape, and the outer edge is used for a hermetically sealed connection with the chamber frame via a sealing ring. A heat exchange system, including an airflow regulation system, is also provided inside the pressure-bearing housing 150 to control the temperature of the upper cover 120. The airflow regulation system may include a helium source, used to circulate gas within the sealed space 160 when it is under low pressure, promoting heat exchange between the upper cover and the pressure-bearing housing, and achieving temperature control of the upper cover. The helium source can achieve a high heat exchange efficiency at a relatively low pressure. Preferably, the pressure regulating device 170 ensures that the pressure on the upper surface of the upper cover 120 is greater than or equal to the pressure in the processing space 140, and less than the pressure on the lower surface of the lower cover 130 during the process.

[0072] like Figure 10 As shown, in some embodiments, after the upper cover 120 is loaded via the assembly ring 1017 and the clamping ring 921, the upper cover 120 and the assembly ring 1017 are jointly installed onto the chamber frame 110. When maintenance of the processing chamber is required after multiple process cycles, the upper cover 120 and the assembly ring 1017 can be disassembled and reinstalled as a whole. Frequent disassembly and reassembly of the two components can cause installation errors at their contact points, thus affecting the sealing effect. In addition, when the two components are made of different materials, the combined effect of different coefficients of thermal expansion during the process will exacerbate this installation error. In this embodiment, the assembly ring 1017 and the chamber frame are made of the same material each time they are disassembled and reassembled, resulting in better compatibility during thermal expansion and maintaining good sealing performance over a long period of time.

[0073] The type of semiconductor processing equipment described in this invention is not limited. For example, the semiconductor processing equipment can be a chemical vapor deposition (CVD) equipment, which is further divided into many types, and is not limited here. The following is a detailed description using the epitaxial equipment in the CVD setup as an example: like Figure 11The diagram shows a schematic of a vapor phase epitaxy apparatus according to the present invention, including a chamber frame 110 with an inlet 111 and an outlet 112 for introducing process gases to form a silicon-containing epitaxial layer on the surface of the substrate W. The inlet 111 and outlet 112 are fitted with an inlet flange 913 and an outlet flange 914. Multiple airflow paths can be provided on the inlet flange 913 to connect to a first process gas 1116, a second process gas 1117, and a purge gas 1118, respectively. An upper cover 120 and a lower cover 130 are disposed opposite each other on both sides of the chamber frame 110. The upper cover 120 is embedded in an opening 915 in the chamber frame 110, and the airtight connection between the upper cover 120 and the chamber frame 110 is reinforced by a clamping ring 921 and a sealing strip 919. A frame 110, an upper cover 120, and a lower cover 130 enclose a processing space 140; a base 990 located within the processing space 140 is used to support the substrate W; and a pressure-bearing housing 150, which is hermetically connected to the chamber frame 110 and, together with the upper cover 120 and the chamber frame 110, encloses a sealed space 160; a pressure regulating device 170 is used to adjust the air pressure in the sealed space 160 during the process so that the air pressure on the upper surface of the upper cover 120 is greater than or equal to the air pressure in the processing space 140 and less than the air pressure on the lower surface of the lower cover 130, thereby reducing the air pressure difference between the upper and lower surfaces of the upper cover 120; a heating lamp assembly 980 located within the sealed space 160 emits heat radiation that can penetrate the upper cover 120 to heat the substrate W.

[0074] In other vapor phase epitaxy devices disclosed in this invention, a heat exchange system 1151 may also be included. This system may be an external airflow regulation system connected to the pressure-bearing housing 150 to promote gas circulation within the sealed space 160 after the pressure regulating device 170 stabilizes the gas pressure, control the temperature of the upper cover 120, and prevent the deposition of process gases on the lower surface of the upper cover 120. The heat exchange system 1151 may also include a fan disposed inside the sealed space 160 to enhance gas circulation within it. The heat exchange system 1151 may also include a cooling fluid circulation system inside the pressure-bearing housing 150 to remove excess heat transferred to the pressure-bearing housing 150.

[0075] The semiconductor processing apparatus and vapor phase epitaxy apparatus disclosed in this invention utilize a pressure-bearing housing positioned above a cover for transmitting thermal radiation. This allows the upper surface of the cover's window to be located within a closed space. A pressure regulating device adjusts the air pressure inside this closed space to be lower than the external atmospheric pressure, reducing the pressure difference the cover must withstand during the process. This allows for the design of a cover window with a smaller thickness to improve thermal radiation transmittance and uniformity, or a cover window with a smaller arch height to improve the stability of the process gas flow within the processing space. Stable flow of process gas within the processing space and efficient and uniform heating of the substrate are crucial factors for uniform and rapid thin film growth. This invention, by placing the upper surface of the cover within a closed space formed by the pressure-bearing housing and adjusting the air pressure within this closed space as a transition between the external atmospheric pressure and the internal processing space pressure, reduces the pressure difference between the upper and lower surfaces of the cover, improving the cover's performance in terms of thermal radiation transmittance and airflow regulation, thereby enhancing the uniformity and stability of substrate processing.

[0076] Although the present invention has been described in detail through the preferred embodiments above, it should be understood that the above description should not be considered as a limitation of the present invention. Various modifications and substitutions to the present invention will be apparent to those skilled in the art after reading the above description. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. A semiconductor processing apparatus, characterized in that, include: A chamber having a sealed processing space, the chamber including a chamber frame and a top cover that allows heat radiation to pass through, the processing space being used to accommodate a substrate; A pressure-bearing housing is disposed above the upper cover and forms a closed space with the upper cover and at least part of the chamber frame, the pressure of the closed space being adjustable; A heating lamp assembly, located in the enclosed space, is used to provide thermal radiation to the substrate through the top cover.

2. The semiconductor processing apparatus as described in claim 1, characterized in that, The chamber frame has an upper surface, a side surface, and a lower surface.

3. The semiconductor processing apparatus as described in claim 2, characterized in that, The upper cover is embedded in the opening on the upper side of the chamber frame and is airtightly connected to the chamber frame. The lower edge of the pressure-bearing shell surrounds the upper cover and is airtightly connected to the upper surface of the chamber frame.

4. The semiconductor processing apparatus as described in claim 3, characterized in that, The opening on the upper side of the chamber frame has a step lower than the upper surface of the chamber frame, and the outer edge of the upper cover overlaps the step and is airtightly connected to the step.

5. The semiconductor processing apparatus as described in claim 4, characterized in that, The outer edge of the top cover is made of opaque quartz material, and a sealing strip is provided between the outer edge of the top cover and the step.

6. The semiconductor processing apparatus as described in claim 5, characterized in that, The outer edge of the top cover is fixed to the chamber frame by a clamping ring, and the pressure-bearing housing is located outside the clamping ring.

7. The semiconductor processing apparatus as claimed in claim 1, characterized in that, The pressure-bearing housing is airtightly connected to the outer wall of the chamber frame by fasteners.

8. The semiconductor processing apparatus as claimed in claim 1, characterized in that, The pressure in the enclosed space is regulated by a pressure regulating device.

9. The semiconductor processing apparatus as claimed in claim 8, characterized in that, The pressure regulating device includes a vacuum pump, and the pressure-bearing housing is connected to the vacuum pump through a sealing pipe.

10. The semiconductor processing apparatus as claimed in claim 8, characterized in that, The voltage regulating device includes: A monitoring module is used to measure the air pressure value of the processing space and / or the enclosed space; The control module is used to preset a safety pressure difference and adjust the pressure of the processing space and the sealed space according to the safety pressure difference based on the pressure value.

11. The semiconductor processing apparatus as claimed in claim 1, characterized in that, The interior of the pressure-bearing shell includes a heat exchange system.

12. The semiconductor processing apparatus as claimed in claim 11, characterized in that, The heat exchange system includes a gas circulation system within the enclosed space.

13. The semiconductor processing apparatus as claimed in claim 12, characterized in that, The gas circulation system includes a fan located in a confined space.

14. The semiconductor processing apparatus as claimed in claim 12, characterized in that, The heat exchange system also includes helium circulating within the enclosed space.

15. The semiconductor processing apparatus as claimed in claim 1, characterized in that, The chamber frame and / or the pressure-bearing shell are made of metal, and the top cover is made of quartz.

16. The semiconductor processing apparatus as claimed in claim 8, characterized in that, The pressure regulating device is used to adjust the pressure of the sealed space to be less than 1 standard atmosphere during the process.

17. The semiconductor processing apparatus as claimed in claim 8, characterized in that, The pressure regulating device is used to adjust the pressure of the sealed space to less than 0.5 standard atmospheres during the process.

18. The semiconductor processing apparatus as claimed in claim 8, characterized in that, The pressure regulating device is used to adjust the pressure in the sealed space to be greater than or equal to the pressure in the processing space during the process.

19. The semiconductor processing apparatus as claimed in claim 1, characterized in that, The top cover includes an annular outer edge and an arched window.

20. The semiconductor processing apparatus as claimed in claim 19, characterized in that, The window includes a central area and an edge area, and the height difference between the two is greater than 0 mm and less than or equal to 25 mm.

21. The semiconductor processing apparatus as claimed in claim 19, characterized in that, The pressure difference between the inside and outside of the window is 0.2 standard atmospheres - 0.8 standard atmospheres.

22. The semiconductor processing apparatus as claimed in claim 2, characterized in that, The chamber also includes a lower cover that is in an atmospheric environment.

23. The semiconductor processing apparatus as claimed in claim 22, characterized in that, The outer edge of the lower cover is airtightly connected to the lower surface of the chamber frame.

24. The semiconductor processing apparatus as claimed in claim 22, characterized in that, The lower cover includes a cylindrical sleeve for passing through a shaft of a support base, and the lower cover also includes a dome-shaped portion extending from the top of the cylindrical sleeve toward the outer edge of the lower cover.

25. The semiconductor processing apparatus as claimed in claim 22, characterized in that, A thermal radiation device located in the atmospheric environment is also provided below the lower cover for heating the substrate through the lower cover.

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