Etching equipment, substrate processing system thereof and device preparation method

Abstract

The invention discloses etching equipment, a substrate processing system thereof and a device preparation method, and the etching equipment is used for forming an isolation groove in the surface of a substrate, and comprises an etching cavity which is provided with a gas transmission port for transmitting etching gas; the base is positioned in the etching cavity and is used for bearing a substrate; the mask plate is located between the gas transmission port and the base, and the distance between the mask plate and the base is adjustable; the mask plate comprises a support plate, a plurality of first gas channels and a plurality of second gas channels, the elastic dielectric layer is located at the bottom of the supporting plate, the bottom of the supporting plate is provided with a plurality of elastic dielectric layer coverage areas and a plurality of second gas channels located between the different elastic dielectric layer coverage areas, and the first gas channels and the second gas channels are communicated and jointly form an etching gas diffusion channel. The etching equipment has the advantages that the mask plate and the base which can move relatively are combined, the substrate processing step is simplified, additional masks and equipment are not needed, and the production input cost is reduced.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor equipment, and in particular to an etching device and a substrate processing system and a device preparation method thereof. Background Art

[0002] With the vigorous development of semiconductor technology, the size of chips is getting smaller and smaller, and the integration of devices is also increasing. In order to ensure the quality of chips, the process requirements for semiconductors are becoming more and more stringent. In order to explore the next generation of power devices, issues such as device integration and size reduction have received widespread attention. By improving the integration of devices, cost-effectiveness and equipment performance can be improved simultaneously. The number of stacking layers of devices also increases. A normal chip requires thousands of process flows from silicon wafers to the final packaging. Multiple process flows have inevitably generated complexity in the processing process, especially in multiple patterning technology.

[0003] In the chip production process, many factors will affect the quality and yield of chip production, such as lattice adaptation, thermal adaptation, stress adaptation between the various layers of chip materials, the number of chip stacking layers, etc., which directly or indirectly determine the quality of the finished chip. For example, the thermal performance adaptability between the underlying substrate of the device and the device layer above the substrate determines the stress of the device during the growth process. If the stress is too large, bending and cracking are likely to occur when growing epitaxial thin films on the underlying substrate, which will lead to defects in the finished device, affecting the quality of the finished device and the finished yield, and further affecting the output and preparation scale of integrated circuits. Therefore, it is necessary to improve the existing production equipment or production methods.

[0004] It should be understood that the above statements merely provide background technology related to the present invention and do not necessarily constitute prior art. Summary of the invention

[0005] Based on the above technical problems, the purpose of the present invention is to provide an etching device and its substrate processing system and device preparation method. The etching device combines a relatively movable mask plate and a base, simplifies the substrate processing steps, eliminates the need for additional masks and equipment, and reduces production input costs.

[0006] In order to achieve the above object, the present invention is implemented by the following technical solutions:

[0007] An etching device, used for forming an isolation groove on a substrate surface, comprising:

[0008] An etching chamber, wherein a gas delivery port is provided on the chamber body, and the gas delivery port is used to deliver etching gas;

[0009] A base for carrying a substrate, which is located inside the etching chamber;

[0010] A mask plate, which is located between the gas delivery port and the base, and the distance between the mask plate and the base is adjustable; wherein the mask plate comprises:

[0011] A support plate having a plurality of first gas channels;

[0012] An elastic medium layer, which is located at the bottom of the support plate, wherein the bottom of the support plate is provided with a plurality of elastic medium layer covering areas, and a plurality of second gas channels located between different elastic medium layer covering areas, wherein the plurality of first gas channels pass through the support plate and are connected with the second gas channels and together constitute an etching gas diffusion channel;

[0013] During the processing, at least part of the bottom of the mask plate is in contact with the upper surface of the substrate, and the area of ​​the upper surface of the substrate not in contact with the bottom of the mask plate is exposed at the outlet of the second gas channel, so that the etching gas contacts the substrate below when flowing in the second gas channel.

[0014] Optionally, the first gas channel includes a through hole;

[0015] And / or, the second gas channel is a through hole or a through groove.

[0016] Optionally, the width of the first gas channel ranges from 5 μm to 10 μm;

[0017] and / or, the width of the second gas channel is less than 15 μm;

[0018] And / or, the width of the second gas channel is greater than or equal to the width of the first gas channel.

[0019] Optionally, the support plate is made of a material comprising metal;

[0020] And / or, the elastic medium layer is made of at least one of fluororubber, Teflon and polymer materials.

[0021] Optionally, also include:

[0022] A gas extraction channel, a gas diffusion space is provided between the mask plate and the gas delivery port, and the gas extraction channel is connected to the first gas channel located at the circumferential edge to discharge reaction waste gas.

[0023] Optionally, a circle of elastic medium layer is provided on the outer periphery of the lower surface of the support plate to form a sealing ring, and the exhaust gas generated in the second gas channel is connected upward to the exhaust channel through the first gas channels located at both ends of the second gas channel and adjacent to the sealing ring.

[0024] Optionally, the upper surface of the support plate includes a plurality of connecting pipes, which are connected between the plurality of first gas channels for exhaust and the exhaust channel; or the upper surface of the support plate includes an annular exhaust ring, which is connected between the plurality of first gas channels for exhaust and the exhaust channel.

[0025] Optionally, the mask plate is connected to the top of the etching chamber via the sidewalls extending upwards, and the mask plate, the sidewalls extending upwards of the mask plate and the top of the etching chamber together surround and form a gas diffusion chamber.

[0026] Optionally, an exhaust port is provided at the bottom of the etching chamber, and the exhaust channel is connected to the exhaust port;

[0027] Alternatively, the exhaust channel passes through an opening on the etching chamber body and is connected to a vacuum extraction device located outside the etching chamber.

[0028] Optionally, a projection of the second gas channel on the substrate coincides with at least a portion of a cutting line of the substrate.

[0029] Optionally, the mask plate is detachable and replaceable.

[0030] Optionally, the mask plate is lifted and lowered by a lifting rod;

[0031] And / or, the base is raised and lowered by a lifting column.

[0032] Optionally, the mask plate includes a downwardly extending portion, and when at least a portion of the bottom of the mask plate is in contact with the upper surface of the substrate, the downwardly extending portion is in contact and pressed against an outer edge of the upper surface of the base.

[0033] Optionally, a corrosion-resistant film layer is provided on the surface of at least a partial area of ​​the mask plate.

[0034] Optionally, also include:

[0035] A remote plasma source, which delivers etching gas into the etching chamber through the gas delivery port;

[0036] Or, a gas supply device, which delivers etching gas into the etching chamber through the gas delivery port.

[0037] Optionally, a substrate processing system comprises:

[0038] The aforementioned etching equipment is used to form isolation grooves on the surface of the substrate;

[0039] A thin film deposition chamber, which is used to deposit a thin film on a substrate surface;

[0040] The transmission chamber is communicated with the etching chamber of the etching device and the thin film deposition chamber respectively.

[0041] Optionally, also include:

[0042] The loading and unloading chamber is communicated with the transmission chamber, and the loading and unloading chamber is used for loading and unloading substrates.

[0043] Optionally, a method for preparing a device comprises:

[0044] growing a buffer layer on the substrate;

[0045] The substrate on which the buffer layer is grown is processed by the aforementioned etching equipment to form an isolation groove on the substrate;

[0046] A thin film is deposited on a substrate including the isolation trench to prepare a target device.

[0047] Optionally, also include:

[0048] Before depositing a thin film on the substrate, the substrate surface is cleaned by a cleaning gas.

[0049] Compared with the prior art, the present invention has the following advantages:

[0050] In an etching device and a substrate processing system and device preparation method thereof of the present invention, the etching device combines a relatively movable mask plate and a base, simplifies the steps of substrate processing, does not require additional masks and equipment, and reduces production investment costs; on the other hand, the mask plate combines a support plate and an elastic medium layer, and the support plate provides support for the mask plate, and the elastic medium layer is in full contact with the substrate to avoid damage to the surface of the substrate. At the same time, the elastic medium layer is in full contact with the substrate surface during the process, which minimizes lateral etching of the substrate surface by plasma and avoids unexpected effects on the substrate surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 This is a schematic diagram of an etching device in Embodiment 1 of the present invention;

[0052] Figure 2 for Figure 1 A top view of the support plate in FIG.

[0053] Figure 3 It is a partial schematic diagram of the mask plate in the first embodiment of the present invention being pressed tightly against the substrate;

[0054] Figure 4 This is a schematic diagram of a substrate processing system in Embodiment 1 of the present invention;

[0055] Figure 5 A schematic diagram of preparing a device in Example 1 of the present invention;

[0056] Figure 6This is a schematic diagram of an etching device in Embodiment 2 of the present invention;

[0057] Figure 7 for Figure 6 A top view of the support plate in FIG.

[0058] Figure 8 It is a schematic diagram of another etching device in the second embodiment of the present invention;

[0059] Fig. 9 for Figure 8 A top view of the support plate in FIG. DETAILED DESCRIPTION

[0060] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0061] It should be noted that, in this article, the terms "include", "comprises", "has" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or terminal device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal device. In the absence of further restrictions, the elements defined by the sentence "includes..." or "comprising..." do not exclude the existence of other elements in the process, method, article or terminal device including the elements.

[0062] As used herein, the term "substrate" refers to and includes a base material or structure on which a material is formed. It should be understood that a substrate may include a single material, a plurality of layers of different materials, one or more layers having regions of different materials or different structures therein, etc. These materials may include semiconductors, insulators, conductors, or combinations thereof. For example, a substrate may be a semiconductor base, a base semiconductor layer on a support structure, a metal electrode or a semiconductor substrate on which one or more layers, structures or regions are formed. The substrate may be a conventional silicon substrate or other bulk substrate including a layer of semiconductor material. The substrate may be doped or undoped.

[0063] It should be noted that the drawings are all in very simplified form and use inaccurate ratios, and are only used to conveniently and clearly assist in explaining the embodiments of the present invention.

[0064] Embodiment 1

[0065] As can be seen from the above, the quality of each layer structure in the semiconductor device is crucial. Based on this, the production quality of the semiconductor device can be improved by forming an isolation groove on the substrate of the semiconductor device. Specifically, the isolation groove divides the entire surface of the substrate into different small-area epitaxial growth areas, which greatly reduces the stress accumulated on the entire surface of the substrate and reduces the possibility of cracking of the thin film deposited on the substrate. At the same time, the size of each small-area epitaxial growth area is small, and its stress can be effectively released without accumulating too much stress to cause cracks in the thin film, which effectively improves the yield rate of the semiconductor device where the substrate is located. Taking a step back, even if cracks occur in the thin film due to certain factors in some individual small-area epitaxial growth areas, the cracks will only extend in the epitaxial growth area and will not spread to other surrounding epitaxial growth areas, thereby ensuring the overall production yield rate of semiconductor devices. However, based on the existing technical concepts, the formation of isolation grooves requires the use of a photolithography method to form a mask on the substrate. This method requires a series of equipment and process flows such as a photolithography machine, an etching machine, a photoresist stripping machine, and a photoresist coating machine. For large-scale mass production, the use of photolithography to form a mask not only occupies a large amount of clean room space, but also requires the additional purchase of the above-mentioned multiple expensive semiconductor processing equipment, which is too costly. Based on the above, the present invention provides an etching device, which is used to form an isolation groove on the surface of a substrate to divide the substrate surface into multiple epitaxial growth areas.

[0066] Specifically, if Figures 1 to 3 As shown, the etching device comprises: an etching chamber 100, a base 110 for carrying a substrate W, and a mask plate 120. A gas inlet 101 is provided on the cavity body of the etching chamber 100, and the gas inlet 101 is used to deliver etching gas. The base 110 is located inside the etching chamber 100, and the mask plate 120 is located between the gas inlet 101 and the base 110. The distance between the mask plate 120 and the base 110 is adjustable. Among them, the mask plate 120 includes a support plate 121 and an elastic medium layer 122, the support plate 121 is provided with a plurality of first gas channels 123, the elastic medium layer 122 is located at the bottom of the support plate 121, the bottom of the support plate 121 is provided with a plurality of elastic medium layer covering areas, and a plurality of second gas channels 124 located between different elastic medium layer covering areas, the elastic medium layer 122 is located on the elastic medium layer covering area, the plurality of first gas channels 123 pass through the support plate 121 to communicate with the second gas channels 124 and together constitute an etching gas diffusion channel.

[0067] During the processing, at least a portion of the bottom of the mask plate 120 is bonded to the upper surface of the substrate W, and the area of ​​the upper surface of the substrate W that is not bonded to the bottom of the mask plate 120 is exposed at the gas outlets of the multiple second gas channels 124, so that the etching gas contacts the upper surface of the substrate W below when flowing through the second gas channels 124, so as to form a plurality of isolation grooves 130, i.e., isolation trenches, on the surface of the substrate W with a pattern similar to that of the second gas channels 124. The etching device enables the substrate W to be etched with patterns at one time without adding an additional mask. The substrate W does not need to be first photolithographically formed with a mask and then etched to form the isolation groove 130. The substrate W does not need to be taken out of the substrate thin film deposition system to the atmospheric environment and then transferred to a series of processing equipment such as a photolithography machine, a glue coater, an etcher, and a glue stripper on the production line. The isolation groove 130 can be formed on the substrate W by only performing etching in the etching chamber 100. This one-step processing method simplifies the processing steps of the substrate W, avoids excessive transportation of the substrate W in the atmospheric environment, and helps to ensure the cleanliness and processing quality of the substrate W, so as to greatly improve the production yield of the device. On the other hand, the mask plate 120 combines the support plate 121 and the elastic medium layer 122. In actual application, the support plate 121 provides support for the mask plate 120, and the elastic medium layer 122 fully contacts the substrate W to avoid damage to the surface of the substrate W (hard damage such as bumps). The etching gas diffusion channel composed of the first gas channel 123 of the support plate 121 and the second gas channel 124 between the elastic medium layer 122 provides a stable gas flow guide for the gas flow of the etching gas, which helps to accurately control the etching to form the isolation groove 130; at the same time, the elastic medium layer 122 fully contacts the surface of the substrate W during the process, and there is no gap between the two, that is, the elastic medium layer 122 covers and protects part of the surface of the substrate W, thereby minimizing the lateral etching of the surface of the substrate W by the plasma and avoiding unexpected impact on the surface of the substrate W.

[0068] like Figure 1 As shown, in this embodiment, the etching device further includes a remote plasma source (RPS) 140, which delivers etching gas to the etching chamber 100 through the gas delivery port 101 for etching. The etching gas is an active group of plasma. After being delivered to the etching chamber 100 through the gas delivery port 101, the active group contacts the surface of the substrate W through the etching gas diffusion channel of the mask plate 120, and then forms an isolation groove 130 by etching on the surface of the substrate W. The bottom of the etching chamber 100 is also provided with an exhaust port 102 to discharge reaction byproducts and / or residual etching gas generated by the etching process to the outside of the chamber.

[0069] The space inside the etching chamber 100 is limited. The remote plasma source 140 directly delivers plasma into the chamber, and there is no need to set up other functional components in the etching chamber 100 to excite the process gas, which reduces the impact on etching. At the same time, the remote plasma source 140 does not occupy the space inside the etching chamber 100, which helps to save the space inside the chamber, so that other functional components that are beneficial to the process can be set up in the chamber. It can be understood that the etching chamber 100 is not limited to providing etching gas through the remote plasma source 140, and it can also be provided by other devices. The present invention is not limited to this, as long as the corresponding etching can be achieved. For example, in another embodiment, the etching equipment includes a gas supply device, which delivers etching gas into the chamber through the gas supply port 101, and the etching gas is a process gas. RF power is applied to the etching chamber 100 through a RF power source (for example, RF power is delivered to the chamber through the base 110), and the process gas is dissociated into plasma, so that plasma is generated between the mask plate 120 and the base 110 for etching. The plasma environment contains a large number of active particles such as electrons, ions, excited atoms, molecules and free radicals. The above-mentioned active particles react with the surface of the substrate W through the second gas channel 124, so as to etch the isolation groove 130 on the surface of the substrate W.

[0070] As mentioned above, the distance between the mask plate 120 and the base 110 is adjustable. Optionally, the mask plate 120 can be raised and lowered to adjust the distance between the two, and / or the base 110 can be raised and lowered to adjust the distance between the two. For example, the mask plate 120 is raised and lowered by a lifting rod; and / or the base 110 is raised and lowered by a lifting column. In this embodiment, Figure 1 As shown, the mask plate 120 is lifted and lowered by three movable lifting rods 125. In an actual process, when a substrate W needs to be transferred to the etching chamber 100, the mask plate 120 is moved upward by the lifting rods 125 to provide a transfer space for the substrate W. After the substrate W is placed on the base 110, the mask plate 120 is driven downward by the lifting rods 125, so that at least a portion of the elastic medium layer 122 at the bottom of the mask plate 120 and the substrate W are in close contact with each other.

[0071] like Figures 1 to 3As shown, in this embodiment, the first gas channel 123 of the support plate 121 is a through-hole structure, so that the support plate 121 has a grid-like pattern of pores and has a higher mechanical strength; the second gas channel 124 at the bottom of the support plate 121 is a through-groove structure, so that the etching gas fully contacts the surface of the substrate W to form a linear isolation groove. The etching gas enters the etching chamber 100 from the gas inlet 101, and flows to each second gas channel 124 through the multiple first gas channels 123 of the support plate 121. The first gas channel 123 of the through-hole structure can further restrict the flow rate of the etching gas, so that the gas flow of the etching gas flows to the second gas channel 124 at a uniform speed. The second gas channel 124 of the through-groove structure provides a uniform gas space for the diffusion of the etching gas, which helps to form a continuous and uniform isolation groove 130 on the surface of the substrate W, so as to divide the substrate W into multiple epitaxial growth areas. It is understandable that the first gas channel 123 is not limited to the above-mentioned through-hole structure, and the second gas channel 124 is not limited to the above-mentioned through-groove structure. In other embodiments, they can also be other structural types, which can be set according to actual needs. For example, the first gas channel 123 can also be a through-groove structure, and the second gas channel 124 can also be a through-hole structure. Similarly, the structural type combination of the first gas channel 123 and the second gas channel 124 is not limited to the above-mentioned combination, and can also be set according to needs in actual applications.

[0072] Optionally, the lateral width of the first gas channel 123 is in the range of 5 μm to 10 μm; and / or the lateral width of the second gas channel 124 is less than 15 μm. Figure 3 As shown, it is a partial schematic diagram of etching in this embodiment. In this embodiment, the width of the second gas channel 124 is greater than the width of the first gas channel 123. The etching gas flows through the long strip second gas channel 124 to etch the surface of the substrate W, and an isolation groove 130 with a width of 15μm and a depth of nanometer level can be formed. It should be noted that the width range of the first gas channel 123 and the second gas channel 124 and the width relationship between the two are not limited to the above. In other embodiments, it can also be other data or relationships. For example, in another embodiment, the width of the second gas channel 124 is equal to the width of the first gas channel 123.

[0073] Optionally, the projection pattern of the second gas channel 124 on the substrate W coincides with at least part of the cutting line of the substrate W, so that the substrate W can be cut when the substrate is separated into independent devices, and the devices on the substrate W will not be affected by the isolation groove 130. In some embodiments, multiple epitaxial growth regions are divided by the projection pattern of the second gas channel 124 on the substrate W. In the process of forming the isolation groove 130, a single epitaxial growth region is covered and protected by the elastic medium layer 122, and a single epitaxial growth region on the substrate W contains one or more devices. In this embodiment, the projections of the multiple second gas channels 124 on the substrate W coincide with all the cutting lines of the substrate W, so as to facilitate the cutting of the substrate W, and at the same time help to ensure the device production yield of multiple epitaxial growth regions on the substrate W. Further, in this embodiment, the mask plate 120 is detachable and replaceable. Optionally, the mask patterns formed by the second gas channels 124 of multiple mask plates 120 are not exactly the same. The corresponding mask plate 120 can be selected according to actual process or product requirements to increase the application range of the etching equipment so that the etching equipment can be used to process substrates W of various chip sizes.

[0074] like Figure 1 As shown, in this embodiment, the mask plate 120 further includes a downwardly extending lower portion 126, and when at least a portion of the bottom area of ​​the mask plate 120 is in contact with the upper surface of the substrate W, the lower portion 126 is in contact and pressed against the outer edge of the upper surface of the pedestal 110. In actual application, the lifting rod 125 drives the mask plate 120 to descend so that the elastic medium layer 122 at the bottom thereof is in contact with the surface of the substrate W, and the lower portion 126 is in contact and pressed against the outer edge of the upper surface of the pedestal 110 to play a sealing role, thereby confining the plasma in the etching gas diffusion channel on the upper surface of the substrate W, preventing the plasma from diffusing and etching to the surface of the pedestal 110, allowing the plasma to react completely on the surface of the substrate W, and the reaction byproducts are discharged through the first gas channel 123 in the edge area of ​​the mask plate 120. In this embodiment, the lower extension 126 surrounds the substrate W, and the bottom of the lower extension 126 includes an elastic medium layer 122 to avoid rigid contact between the lower extension 126 and the upper surface of the base 110 , thereby reducing damage to the upper surface of the base 110 caused by the mask plate 120 .

[0075] Optionally, the material for preparing the support plate 121 includes metal, so that the support plate 121 is formed into a hard cover plate to provide sufficient strength support for the mask plate 120; and / or, the material for preparing the elastic medium layer 122 includes at least one of fluororubber, Teflon, and polymer materials, so that there is a flexible buffer between the contact surface of the mask plate 120 and the substrate W. Of course, the support plate 121 and the elastic medium layer 122 can also be prepared from other materials, and the present invention is not limited to this. Furthermore, the surface of at least part of the area of ​​the mask plate 120 (mainly the area in contact with the plasma) is provided with a corrosion-resistant film layer to avoid affecting the mask plate 120, which helps to improve the service life of the mask plate 120. By way of example, the corrosion-resistant film layer is a coated plasma corrosion-resistant coating.

[0076] Furthermore, the present invention also provides a substrate processing system, which comprises: the aforementioned etching equipment, a thin film deposition chamber and a transfer chamber (TM). The etching equipment is used to form an isolation groove 130 on the surface of the substrate W, the thin film deposition chamber is used to deposit a thin film on the surface of the substrate W, and the transfer chamber is connected to the etching chamber 100 of the etching equipment and the thin film deposition chamber respectively. Figure 4 As shown, in this embodiment, the substrate processing system is a MOCVD processing system, which includes an etching device, a transmission chamber 300 and a plurality of thin film deposition chambers 200 (MOCVD chambers), and the transmission chamber 300 is respectively connected with the etching chamber 100 and the thin film deposition chamber 200 of the etching device. The substrate W can be directly processed and etched in the etching chamber 100 to form an isolation groove 130. Since the transmission chamber 300 is respectively connected with the etching chamber 100 and the thin film deposition chamber 200, after the isolation groove 130 is formed in the etching chamber 100, the substrate W can be directly transferred from the etching chamber 100 to the thin film deposition chamber 200 through the transmission chamber 300, and the subsequent epitaxial film growth is started after the cleaning step (it can also be cleaned in the etching chamber 100), until the required device (such as LED, power device, laser device, etc.) is formed. The etching device makes it unnecessary for the substrate W to be transferred in the atmospheric environment for many times, avoids damage to the substrate W, reduces the operation steps, and improves the processing efficiency of the substrate W.

[0077] Furthermore, in this embodiment, the substrate processing system also includes a loading and unloading chamber (LL) 400 and a transfer chamber 500. The transmission chamber 300 is connected to the loading and unloading chamber 400 and the transfer chamber 500 respectively. The loading and unloading chamber 400 is used for loading and unloading the substrate W. The loading and unloading chamber 400 is located between the atmospheric environment and the vacuum chamber, and its vacuum degree can be changed; the transfer chamber 500 is used for temporarily storing the substrate W.

[0078] It should be noted that the substrate processing system is not limited to the above-mentioned. In other embodiments, other types or numbers of chambers or equipment may be provided according to actual needs, and the present invention is not limited thereto.

[0079] Based on the same inventive concept, the present invention also provides a method for preparing a device, which comprises: growing a buffer layer on a substrate W; processing the substrate W with the buffer layer by using the etching equipment as mentioned above to form an isolation groove 130 on the substrate W; and depositing a thin film on the substrate W including the isolation groove 130 to prepare a target device.

[0080] Furthermore, the method for preparing the device further comprises: before depositing the thin film on the substrate W, cleaning the surface of the substrate W by using a cleaning gas. Optionally, the surface of the substrate W may be cleaned by using a cleaning gas in the etching chamber 100 of the etching device, or may be cleaned by using a cleaning gas in the thin film deposition chamber 200. During the cleaning process in the etching chamber 100, a cleaning gas (such as H2O2) may be delivered into the chamber through the gas delivery port 101 of the etching chamber 100. 2 ), after etching the substrate W to form the isolation groove 130, the etching gas introduced is converted into a cleaning gas to remove the residual etching gas and reaction by-products in the etching gas diffusion channel, and then the distance between the mask plate 120 and the base 110 is adjusted to separate the substrate W from the mask plate 120.

[0081] like Figure 5 As shown, it is a schematic diagram of the preparation of a semiconductor device, which includes a base layer 610, a buffer layer 620 and a power device layer 640 arranged in sequence from bottom to top. Specifically, in this embodiment, the semiconductor device is a GaN power device, which includes a silicon substrate, i.e., a base layer 610, a buffer layer 620, a super seed layer (supper lattice) 630 and a GaN device layer, i.e., a power device layer 640, which are stacked in sequence from bottom to top. Since the lattice mismatch and thermal mismatch between the silicon substrate and the GaN film are relatively large, huge stress is easily introduced during the growth process. In order to buffer the mismatch between the silicon substrate and the GaN film, a buffer layer 620 and a super seed layer 630 are arranged between the two. The buffer layer 620 includes AlN, and the super seed layer 630 includes a material layer of AlN / GaN alternating cycles. Through this multilayer structure, the stress of the device is released to reduce the deformation of the overall device.

[0082] like Figure 5As shown, in this embodiment, during the actual preparation, A. first grow a buffer layer 620 on the base layer 610; B. cool the base layer 610 with the buffer layer 620 and then transfer it into the etching chamber 100 of the etching equipment to form the isolation groove 130. Specifically, in the etching chamber 100, the mask plate 120 with the etching pattern (etching gas diffusion channel) is pressed against the base layer 610 with the buffer layer 620, and the buffer layer 620 etching gas is transported into the chamber through the gas delivery port 101 of the etching chamber 100 to etch the isolation groove 130 on the surface of the buffer layer 620. The substrate W after the etching process is transferred from the etching chamber 100 to the thin film deposition chamber 200 through the transmission chamber 300, and C. the cleaning gas H is introduced into the thin film deposition chamber 200. 2 Remove the residual organic matter; D, and then continue the subsequent MOCVD process to epitaxially grow the super seed layer 630 and the GaN device layer. As can be seen from the figure, when the device layer continues to be epitaxially grown on the substrate W with the isolation groove 130, the cross section of the epitaxial layer grown on the isolation groove 130 is a V-shaped or U-shaped structure, and the thickness of the epitaxial layer at the isolation groove 130 is slightly different (slightly thinner) from the thickness of the corresponding device layer on the epitaxial growth area, which helps to reduce the correlation between devices in adjacent epitaxial growth areas and reduce the influencing factors of the devices in the epitaxial growth area, so as to improve the yield rate of device production.

[0083] It is understandable that the present invention can not only form the isolation groove 130 by etching the buffer layer 620 of the semiconductor device, but also form the isolation groove 130 by etching other layers. The method can be selected according to actual needs as long as the overall surface stress of the substrate W can be improved.

[0084] Embodiment 2

[0085] Based on the structural characteristics of the plasma processing device in the first embodiment, this embodiment mainly makes some changes to the structure of the mask plate 720 .

[0086] like Figure 6As shown, in this embodiment, the mask plate 720 includes a support plate 721 and a plurality of elastic medium layers 722. Similar to the first embodiment, the mask plate 720 includes an etching gas diffusion channel composed of a first gas channel 723 of the support plate 721 and a plurality of second gas channels 724 between the coverage areas of different elastic medium layers 722. Different from the first embodiment, in this embodiment, the mask plate 720 further includes an exhaust channel 726, and a gas diffusion space is provided between the mask plate 720 and the gas delivery port 701. The exhaust channel 726 is connected to the first gas channel 723 located at the radial edge of the plurality of second gas channels 724, that is, the exhaust port 727 of the exhaust channel 726 is connected to at least a portion of the first gas channel 723 located at the upper edge of the mask plate 720. Because the second gas channels 724 formed between the elastic medium layers 722 are connected to each other, the exhaust channel 726 can discharge the reaction waste gas (including residual etching gas and / or reaction by-products) formed on the upper surface of the substrate, and promote the reaction gas to flow downward from the gas diffusion space 740.

[0087] In practical applications, the thickness of the support plate 721 and the elastic medium layer 722 will not be too high (may only need a few millimeters). After the etching gas molecules diffuse from the gas delivery port 701 to the second gas channel 724 and contact the surface of the substrate W, the residual etching gas or reaction by-products at the second gas channel 724 can hardly be discharged through the etching gas diffusion channel on the mask plate 720 in a short time by free diffusion. The residual etching gas or reaction by-products will corrode the area on the substrate W that is not desired to be etched (such as the area where the device needs to be prepared) and multiple components in the etching chamber 700, that is, the etching gas and reaction by-products will have some negative effects if they stay on the substrate W or in the etching chamber 700 for too long. Based on this, the present embodiment sets a gas extraction channel 726 at the edge of the mask plate 720, and adopts an auxiliary gas extraction method to speed up the gas flow rate, quickly discharge the residual etching gas and reaction by-products, and do not leave the residual etching gas and reaction by-products above the substrate W, thereby ensuring accurate control of etching and avoiding excessive etching of the substrate W to affect the device utility.

[0088] Optionally, the exhaust channel 726 passes through an opening on the etching chamber 700 and is connected to a vacuum extraction device located outside the etching chamber 700 to exhaust the reaction waste gas. Figure 6As shown, in this embodiment, the opening on the cavity body of the etching cavity 700 is the opening at the top of the cavity body. Further, the mask plate 720 is connected to the top of the etching cavity 700 through the side wall extending upward, and the mask plate 720, the side wall extending upward of the mask plate 720 and the top of the etching cavity 700 together surround and form a gas diffusion cavity 740, so that the etching gas can only diffuse in the gas diffusion cavity 740 and the etching gas diffusion channel during the process, and will not leak to other areas in the etching cavity 700, which not only improves the utilization rate of the etching gas, but also further ensures that other areas in the cavity will not be affected by the etching gas. Optionally, a corrosion-resistant film layer can be set only in the gas diffusion cavity 740 and the etching gas diffusion channel. Further, in this embodiment, the base 710 is raised and lowered by a lifting column 725.

[0089] Furthermore, in this embodiment, a circle of elastic medium layer 722 is provided at the outer periphery of the lower surface of the support plate 721 to form a sealing ring, and the waste gas generated in the second gas channel 724 is upwardly connected to the exhaust channel 726 through the first gas channels 723 located at both ends of the second gas channel 724 and adjacent to the sealing ring. The sealing ring on the lower surface of the support plate 721 can confine the etching gas to the area where the substrate W is located, and will not diffuse to the surrounding area of ​​the substrate W.

[0090] In this embodiment, the upper surface of the support plate 721 includes a plurality of connecting pipes 728, and the plurality of connecting pipes 728 are connected between the plurality of first gas channels 723 for exhaust and the exhaust channel 726. The connection ports of the plurality of connecting pipes 728 and the first gas channels 723 are equivalent to the exhaust ports 727 of the exhaust channels 726. After the etching gas enters the grid-shaped second gas channel 724 through the first gas channel 723, it flows along the long groove-shaped second gas channel 724 until it enters the exhaust channel 726 from the first gas channel 723 at the edge of the support plate 721, and then is discharged from the etching chamber 700 from the exhaust channel 726.

[0091] Preferably, the air extraction ports 727 of the air extraction channel 726 are evenly arranged along the circumference of the edge of the mask plate 720 (see Figure 7 ), so that the driving or extraction effect of the mask plate 720 on the gas in all directions is the same, which helps to ensure the uniformity of the surface treatment of the substrate W, that is, the isolation groove structure formed at various locations on the surface of the substrate W is the same. Of course, the arrangement of the gas extraction port 727 of the gas extraction channel 726 is not limited to the above-mentioned manner, and can also be arranged in other ways as needed, for example, by arranging the gas extraction channel 726, the driving or extraction effect of a specific position on the gas is different from that of other positions, and the present invention is not limited to this.

[0092] It should be noted that the present invention does not limit the communication mode between the exhaust channel 726 and the outside of the cavity, as long as exhaust to the outside of the cavity can be achieved. For example, in another embodiment, an exhaust port 702 is provided at the bottom of the etching cavity 700, and the exhaust channel 726 is connected to the exhaust port 702. Furthermore, the present invention does not limit the communication mode between the first gas channel 723 for exhaust in the support plate 721 and the exhaust channel 726, as long as the corresponding functional role can be achieved. For example, Figure 8 and Fig. 9 As shown, in another embodiment, the upper surface of the support plate 821 includes an annular exhaust ring 825, and the exhaust ring is connected between the plurality of first gas channels 823 for exhaust and the exhaust channel 826. In this embodiment, the exhaust channel 826 is an exhaust pipe arranged on the outer wall of the support plate 821, and the exhaust pipe extends downward from the exhaust ring to the bottom of the reaction chamber (which can be connected to the exhaust port 802) to prevent the etching gas and reaction by-products from contaminating the side and bottom of the substrate W. Further, the etching equipment can also deliver purification gas into the chamber through the gas delivery port 801 to purify the surface of the substrate W after the etching is completed. During the etching process, the exhaust ring around the support plate 821 can be slowly evacuated so that the etching gas stays in the etching gas diffusion channel for a long time to produce a sufficient amount of etching on the surface of the substrate W. After etching is completed, the etching gas delivered by the gas inlet 801 can be switched to high-speed purification gas and sprayed downward. At the same time, the exhaust ring is also changed to high-speed exhaust, so that the residual etching gas and reaction by-products in the etching gas diffusion channel can be extracted as soon as possible, and then the base 810 is lowered to separate the substrate W from the mask plate 820 above it.

[0093] In addition, other structures and functions of various components of this embodiment, such as the structure of the first gas channel 723 and the structure of the second gas channel 724, may be similar to or the same as those in the first embodiment, and will not be described in detail here.

[0094] In summary, in an etching device and a substrate processing system and a device preparation method of the present invention, the etching device combines a mask plate 120 having a support plate 121 and an elastic medium layer 122 with a base 110, and in the process, at least a part of the bottom area of ​​the mask plate 120 is fitted with the upper surface of the substrate W, so that the etching gas contacts the surface of the substrate W in the etching gas diffusion channel of the mask plate 120 to etch the isolation groove 130 on the surface of the substrate W. The device simplifies the steps of processing the surface of the substrate W, forms a patterned etching at one time without adding an additional mask, and makes the surface of the substrate W have multiple isolation grooves 130, so as to reduce the overall stress of the substrate W surface and improve the yield rate of device production. At the same time, the etching device makes it unnecessary to add a series of expensive equipment such as a photolithography machine and a photoresist coating machine to the entire substrate processing system, reducing the production input cost and greatly improving the economic benefits of device production. On the other hand, the mask plate 120 is in contact with the substrate W through the elastic medium layer 122 at the bottom of the support plate 121, thereby avoiding hard damage to the surface of the substrate W and helping to ensure the quality of device production.

[0095] Although the content of the present invention has been described in detail through the above preferred 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. An etching device, characterized in that: The method is used to form an isolation groove on the surface of a substrate, and comprises: An etching chamber, wherein a gas delivery port is provided on the chamber body, and the gas delivery port is used to deliver etching gas; A base for carrying a substrate, which is located inside the etching chamber; A mask plate, which is located between the gas delivery port and the base, and the distance between the mask plate and the base is adjustable; wherein the mask plate comprises: A support plate having a plurality of first gas channels; An elastic medium layer, which is located at the bottom of the support plate, wherein the bottom of the support plate is provided with a plurality of elastic medium layer covering areas, and a plurality of second gas channels located between different elastic medium layer covering areas, wherein the plurality of first gas channels pass through the support plate and are connected with the second gas channels and together constitute an etching gas diffusion channel; During the processing, at least part of the bottom of the mask plate is in contact with the upper surface of the substrate, and the area of ​​the upper surface of the substrate not in contact with the bottom of the mask plate is exposed at the outlet of the second gas channel, so that the etching gas contacts the substrate below when flowing in the second gas channel.

2. The etching device according to claim 1, characterized in that: The first gas channel includes a through hole; And / or, the second gas channel is a through hole or a through groove.

3. The etching device according to claim 1, characterized in that: The width of the first gas channel ranges from 5 μm to 10 μm; and / or, the width of the second gas channel is less than 15 μm; And / or, the width of the second gas channel is greater than or equal to the width of the first gas channel.

4. The etching device according to claim 1, characterized in that: The support plate is made of a material comprising metal; And / or, the elastic medium layer is made of at least one of fluororubber, Teflon and polymer materials.

5. The etching device according to claim 1, characterized in that: Also includes: A gas extraction channel, a gas diffusion space is provided between the mask plate and the gas delivery port, and the gas extraction channel is connected to the first gas channel located at the circumferential edge to discharge reaction waste gas.

6. The etching device according to claim 5, characterized in that: The outer periphery of the lower surface of the support plate is provided with a circle of elastic medium layer to form a sealing ring, and the waste gas generated in the second gas channel is upwardly connected to the exhaust channel through the first gas channels located at both ends of the second gas channel and adjacent to the sealing ring.

7. The etching device according to claim 6, characterized in that: The upper surface of the support plate includes a plurality of connecting pipes, which are connected between the plurality of first gas channels for exhaust and the exhaust channel; or the upper surface of the support plate includes an annular exhaust ring, which is connected between the plurality of first gas channels for exhaust and the exhaust channel.

8. The etching device according to claim 5, characterized in that: The mask plate is connected to the top of the etching chamber via the side wall extending upwards, and the mask plate, the side wall extending upwards of the mask plate and the top of the etching chamber together surround and form a gas diffusion chamber.

9. The etching device according to claim 5, characterized in that: An exhaust port is provided at the bottom of the etching chamber, and the exhaust channel is connected to the exhaust port; Alternatively, the exhaust channel passes through an opening on the etching chamber body and is connected to a vacuum extraction device located outside the etching chamber.

10. The etching device according to claim 1, characterized in that: A projection of the second gas channel on the substrate coincides with at least a portion of a cutting line of the substrate.

11. The etching device according to claim 1, characterized in that: The mask plate is detachable and replaceable.

12. The etching device according to claim 1, characterized in that: The mask plate is lifted and lowered by a lifting rod; And / or, the base is raised and lowered by a lifting column.

13. The etching device according to claim 1, characterized in that: The mask plate comprises a downwardly extending portion, and when at least a portion of the bottom of the mask plate is in contact with the upper surface of the substrate, the downwardly extending portion is in contact and pressed against the outer edge of the upper surface of the base.

14. The etching device according to claim 1, characterized in that: A corrosion-resistant film layer is provided on the surface of at least a portion of the mask plate.

15. The etching device according to claim 1, characterized in that: Also includes: A remote plasma source, which delivers etching gas into the etching chamber through the gas delivery port; Or, a gas supply device, which delivers etching gas into the etching chamber through the gas delivery port.

16. A substrate processing system, characterized in that: Include: The etching device according to any one of claims 1 to 15, which is used to form an isolation groove on the surface of a substrate; A thin film deposition chamber, which is used to deposit a thin film on a substrate surface; The transmission chamber is communicated with the etching chamber of the etching device and the thin film deposition chamber respectively.

17. The substrate processing system according to claim 16, wherein: Also includes: The loading and unloading chamber is communicated with the transmission chamber, and the loading and unloading chamber is used for loading and unloading substrates.

18. A method for preparing a device, characterized in that: Include: growing a buffer layer on the substrate; Processing the substrate on which the buffer layer is grown by using the etching device as claimed in any one of claims 1 to 15 to form an isolation groove on the substrate; A thin film is deposited on a substrate including the isolation trench to prepare a target device.

19. The method for preparing a device according to claim 18, characterized in that: Also includes: Before depositing a thin film on the substrate, the substrate surface is cleaned by a cleaning gas.

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