Backside gas intake assembly for thermal annealing apparatus and thermal annealing apparatus

Abstract

Provided in the present application are a backside gas intake assembly for a thermal annealing apparatus and a thermal annealing apparatus. The backside gas intake assembly comprises: a reflector plate configured to reflect radiation energy emitted by a wafer to the back face of the wafer; and a gas intake assembly, which is made of a transparent material, is arranged on the reflector plate and has a gas intake inner cavity and gas output holes, wherein the gas output holes are in communication with the gas intake inner cavity, and an inert gas entering the gas intake inner cavity is dispersed in the gas intake inner cavity and then flows to the back face of the wafer through the gas output holes. When the backside gas intake assembly described above is used to deliver gas to the back face of the wafer, the inert gas first flows into the gas intake inner cavity and diffuses therein to reduce the gas pressure and flow rate, such that the inert gas is blown to the wafer at a lower gas pressure and flow rate, thereby preventing the wafer from shifting; and the inert gas enters the gas output holes after diffusing in the gas intake inner cavity, and since the inert gas is dispersed in the gas intake inner cavity, the inert gas purges the back face of the wafer more uniformly through the gas output holes, such that the wafer can be cooled more uniformly.

Description

Backside gas inlet assembly for a thermal annealing apparatus and thermal annealing apparatus TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor equipment, in particular to a backside gas inlet assembly for a thermal annealing apparatus and a thermal annealing apparatus. BACKGROUND

[0002] With the rapid iteration of integrated circuit technology, the process requirements for chips are also increasingly high, which in turn leads to the need for better rapid thermal annealing (RTA) of wafers during wafer manufacturing, that is, faster heating rates and shorter high-temperature intervals (the high-temperature interval is T-50, that is, the time experienced by the peak temperature minus 50℃ in the rapid thermal annealing process, which includes the time from 50℃ to the peak temperature and the time from the peak temperature to 50℃, which is a key parameter for evaluating the rapid thermal annealing process). At present, one of the main ways to improve T-50 is to introduce helium (He) into the backside space of the wafer to cool the back of the wafer (i.e., back helium gas inlet).

[0003] However, the back helium gas inlet effect of the existing gas inlet assembly is not ideal, which has the following problems: 1. The pressure and flow rate of helium blowing to the back of the wafer are large, which can easily blow the wafer and cause displacement, affecting process stability; 2. The helium gas inlet in the backside space is not uniform, and the cooling effect is poor. SUMMARY

[0004] Therefore, the present application provides a backside gas inlet assembly for a thermal annealing apparatus, which can avoid the displacement of the wafer and improve the cooling effect of the wafer. In addition, the present application also provides a thermal annealing apparatus.

[0005] In order to achieve the above purpose, the present application provides the following technical solutions:

[0006] A backside gas inlet assembly for a thermal annealing apparatus for introducing gas to the back of a wafer located in a reaction chamber, comprising:

[0007] a reflection plate for reflecting the radiation energy emitted by the wafer to the back of the wafer;

[0008] a gas inlet assembly made of transparent material and arranged on the reflection plate, and having a gas inlet cavity and a gas outlet hole, the gas outlet hole being in communication with the gas inlet cavity;

[0009] wherein the inert gas entering the gas inlet cavity is dispersed in the gas inlet cavity and then flows to the back of the wafer through the gas outlet hole.

[0010] In some embodiments of the backside gas inlet assembly for the thermal annealing apparatus, the gas outlet holes are provided in a plurality and are used to direct the inert gas to different parts of the backside of the wafer.

[0011] In some embodiments of the backside gas inlet assembly for the thermal annealing apparatus, a flow guide structure is provided in the gas inlet cavity to guide the inert gas to the gas outlet holes.

[0012] In some embodiments of the backside gas inlet assembly for the thermal annealing apparatus, the gas inlet cavity is provided in a plurality and is isolated from each other, each of the gas inlet cavities has a gas inlet channel, and the gas outlet holes are provided in a plurality, and each of the gas inlet cavities is in communication with the gas outlet holes distributed in the area where the gas inlet cavity is located.

[0013] In some embodiments of the backside gas inlet assembly for the thermal annealing apparatus, the gas inlet assembly has a gas outlet surface facing the backside of the wafer.

[0014] In some embodiments of the backside gas inlet assembly for the thermal annealing apparatus, the gas outlet holes are provided in a plurality, and all the gas outlet holes are arranged in a plurality of straight lines on the gas outlet surface, and the plurality of straight lines are uniformly distributed on the gas outlet surface.

[0015] In some embodiments of the backside gas inlet assembly for the thermal annealing apparatus, the gas inlet assembly comprises:

[0016] a first plate body covering the reflective plate and provided with a gas inlet channel;

[0017] a second plate body provided with the gas outlet holes and stacked on the first plate body;

[0018] In some embodiments of the backside gas inlet assembly for the thermal annealing apparatus, a groove is provided on the first plate body and / or the second plate body, and the first plate body and the second plate body are laminated to close the groove to form the gas inlet cavity.

[0019] In some embodiments of the backside gas inlet assembly for the thermal annealing apparatus, the groove is provided on the surface of the second plate body facing the first plate body.

[0020] In some embodiments of the backside gas inlet assembly for the thermal annealing apparatus, a flow guide structure is provided in the gas inlet cavity, and the flow guide structure comprises arc-shaped protrusions in the groove and protruding relative to the bottom wall of the groove, a plurality of the protrusions enclose a flow guide ring having a radial opening, and the flow guide ring has a plurality of concentrically arranged.

[0021] In some embodiments of the backside gas inlet assembly for the thermal annealing apparatus, the groove is provided on the surface of the second plate body facing the first plate body, a convex ring protruding relative to the bottom wall of the groove is provided on the bottom wall of the groove, and the convex ring is in abutment with the first plate body to isolate the inner groove cavity and the outer groove cavity of the convex ring to form a plurality of the gas inlet cavities.

[0022] In some embodiments, in the back-side air intake assembly for the hot annealing equipment described above, a plurality of concentric convex rings are provided in the groove to form a plurality of circular and annular air intake cavities.

[0023] In some embodiments, in the aforementioned back-side air intake assembly for the thermal annealing equipment...

[0024] Each of the aforementioned air intake cavities is provided with the air intake channel, and:

[0025] The circular air intake cavity is a central air intake cavity located in the central region of the second plate, and the air intake channel of the central air intake cavity is located at the center of the central air intake cavity.

[0026] The annular plurality of air intake cavities include an intermediate air intake cavity and an outer air intake cavity that surround the central air intake cavity and are nested therein in sequence. The air intake channel provided in the outer air intake cavity is located near the outer edge of the outer air intake cavity; the air intake channel provided in the intermediate air intake cavity is located near the inner edge of the intermediate air intake cavity.

[0027] In some embodiments, in the above-described back-side air intake assembly for a hot annealing apparatus, at least one of the air intake cavities has a plurality of air intake channels, and the plurality of air intake channels communicating with the same air intake cavity are symmetrically arranged about the center of the convex ring.

[0028] In some embodiments, in the above-described back-side air intake assembly for a hot annealing apparatus, the air intake channel protrudes from the first plate in a direction away from the second plate and passes through the reflector.

[0029] In some embodiments, the air supply pipeline for supplying the inert gas in the above-described back air intake assembly for the hot annealing equipment includes multiple branch pipelines connected to different air intake channels, and each branch pipeline is equipped with a flow controller.

[0030] In some embodiments, in the back-side air intake assembly for the hot annealing equipment described above, the surface of the second plate facing away from the first plate is the air outlet surface. Multiple air outlets are provided, and all the air outlets are arranged in multiple straight lines on the air outlet surface. All the multiple straight lines pass through the center of the air outlet surface, and the included angle between any two adjacent straight lines is equal.

[0031] As another technical solution, a hot annealing device includes the aforementioned back-side air intake assembly for hot annealing devices.

[0032] In some embodiments, the above-described heat annealing apparatus further includes:

[0033] a reaction chamber;

[0034] a bearing structure arranged in the reaction chamber, having a bearing surface for bearing a wafer, and capable of driving the wafer to rotate;

[0035] a heating light source arranged above the bearing structure, for providing heat required by the wafer;

[0036] a quartz light-transmitting plate arranged between the heating light source and the bearing structure, for isolating the heating light source and the bearing structure, and allowing heat generated by the heating light source to pass through;

[0037] a support structure for supporting the backside gas inlet assembly, and making the top surface of the backside gas inlet assembly be located below the bearing surface for bearing the wafer;

[0038] a temperature detector arranged on the support structure and / or the backside gas inlet assembly, for detecting the temperature of the wafer.

[0039] The backside gas inlet assembly for the thermal annealing apparatus provided in the present application adds a gas inlet assembly for the backside of the wafer on the reflecting plate. The gas inlet assembly has a gas inlet inner cavity and a gas outlet hole in communication with the gas inlet inner cavity. In the process of flowing to the backside of the wafer, the inert gas first enters the gas inlet inner cavity, and is dispersed in the gas inlet inner cavity to reduce the gas pressure and flow rate, and then the inert gas is blown to the backside of the wafer through the gas outlet hole. Since the inert gas is blown to the backside of the wafer after being dispersed in the gas inlet inner cavity, the backside of the wafer can be cooled more uniformly. Since the gas pressure and flow rate of the inert gas blown out of the gas outlet hole are reduced in the gas inlet inner cavity, the wafer can be prevented from being deviated by the inert gas. BRIEF DESCRIPTION OF DRAWINGS

[0040] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the related art, the drawings needed to be used in the embodiments or the related art description will be briefly introduced. Obviously, the drawings in the following description are only embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative effort on the basis of the provided drawings.

[0041] FIG. 1 is a structural schematic view of part of components of a thermal annealing apparatus in the related art;

[0042] FIG. 2 is a top view of a reflecting plate in the related art;

[0043] FIG. 3 is a structural schematic view of part of components of a thermal annealing apparatus provided in an embodiment of the present application;

[0044] FIG. 4 is a structural schematic view of cooperation of a first plate body, a second plate body and a gas supply pipeline;

[0045] Fig. 5 is a schematic diagram of the structure of the convex strip and the convex ring arranged on the second plate body;

[0046] Fig. 6 is a schematic diagram of the structure of the distribution of the air outlet holes on the air outlet surface of the second plate body;

[0047] Fig. 7 is a schematic diagram of the structure of the distribution of the through holes on the reflection plate.

[0048] In Figs. 1 and 2: 01 - bearing structure, 02 - heating light source, 03 - wafer, 04 - quartz light transmission plate, 05 - base, 06 - temperature measuring instrument, 07 - reflection plate, 08 - air outlet;

[0049] In Figs. 3-7: 1 - bearing structure, 2 - heating light source, 3 - wafer, 4 - quartz light transmission plate, 5 - support structure, 6 - side temperature measuring instrument, 7 - air supply pipeline, 8 - reflection plate, 9 - first plate body, 10 - second plate body, 11 - air inlet cavity, 12 - air outlet hole, 13 - air outlet surface, 14 - convex strip, 15 - convex ring, 16 - air inlet channel, 17 - central air inlet cavity, 18 - intermediate air inlet cavity, 19 - side wall, 20 - outer side air inlet cavity, 21 - branch pipeline, 22 - flow controller, 23 - radial opening, 24 - through hole. DETAILED DESCRIPTION

[0050] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of protection of the present application.

[0051] In the related art, as shown in Fig. 1, the thermal annealing device includes a bearing structure 01, a heating light source 02, a quartz light transmission plate 04, a base 05, a temperature measuring instrument 06, a reflection plate 07, etc., wherein the light spot emitted by the heating light source 02 transmits through the quartz light transmission plate 04 to irradiate on the wafer 03, the reflection plate 07 is connected with the base 05, and the reflection plate 07 is used for reflecting the radiant energy emitted from the back surface of the wafer 03, as shown in Fig. 2, the air outlet 08 is arranged on the surface of the reflection plate 07 facing the wafer 03, the inert gas (for example, helium) enters the reaction chamber through the air outlet 08 from the back surface (the surface facing away from the wafer 03) of the reflection plate 07, and the inert gas flowing into the reaction chamber flows through the back surface of the wafer 03, so as to realize the improvement of the wafer 03 cooling rate.

[0052] However, in the related art, the gas outlet angle of the gas outlet 08 arranged along the radius direction of the reflection plate 07 is fixed. After the helium gas is discharged from the gas outlet 08, under the condition that the front end pressure of the helium gas is high or the use flow is large, it will directly cause the wafer 03 to displace, the wafer 03 work station abnormal (OOP: Out of Pocket) alarm, and directly affect the product process stability. At the same time, as shown in FIG. 2, in the related art, the reflection plate 07 is used to provide helium gas to the wafer 03. Since the gas outlets 08 are not uniformly arranged on the reflection plate 07, it cannot stably achieve uniform cooling of the wafer 03, and when the flow of the back helium exceeds 1.5 slm, the cooling rate will no longer increase, which cannot meet the demand for shorter high temperature interval (T-50) under advanced process. In addition, in the related art, the thermal annealing equipment has a degassing treatment working condition and a thin film growth working condition. In the degassing treatment working condition, the coating on the surface of the reflection plate 07 may fall off or be eroded. In the thin film growth working condition, the coating on the surface of the reflection plate 07 will also be affected, and there is a problem that the reflection efficiency of the reflection plate 07 will be significantly reduced, and the service life will be significantly shortened.

[0053] Based on the above situation, the embodiment of the present application provides a backside gas inlet assembly which can be applied to a thermal annealing equipment to realize rapid thermal annealing of a wafer 3.

[0054] In order to facilitate the description of the backside gas inlet assembly, the main structure of the thermal annealing equipment is first described: as shown in FIG. 3, the thermal annealing equipment includes a reaction chamber, a bearing structure 1, a heating light source 2, a quartz light transmission plate 4, a support structure 5, a temperature measuring instrument 6 and a backside gas inlet assembly. The heating light source 2 is arranged in the top space of the reaction chamber, and the heating light source 2 can be composed of a plurality of halogen infrared heating lamps. The quartz light transmission plate 4 is located between the heating light source 2 and the bearing structure 1, which is used to isolate the heating light source 2 to avoid the influence of the process gas on the heating light source 2 during the process, and the quartz light transmission plate 4 also allows the heat generated by the heating light source 2 to pass through to provide the heat required by the wafer 3 during the process. The bearing structure 1 is a placement and support structure for the wafer 3, which has a bearing surface for bearing the wafer 3, thereby forming a placement position of the wafer 3 in the reaction chamber. The process of the wafer 3 is completed under the horizontal bearing of the bearing structure 1, and in order to meet the process requirements, the bearing structure 1 can drive the wafer 3 to rotate at a high speed around the center of the bearing structure 1 while bearing the wafer 3. The bearing structure 1 specifically includes a magnetic levitation rotor and a support arranged on the magnetic levitation rotor. The support structure 5 is arranged in the bottom space of the reaction chamber, which is used to support the above-mentioned backside gas inlet assembly, that is, the backside gas inlet assembly is arranged on the support structure 5, and the top surface (i.e. the gas inlet surface described later) of the backside gas inlet assembly is located below the bearing surface of the bearing structure 1, so that the backside gas inlet assembly is located below the wafer 3 and can blow gas to the back of the wafer 3. The temperature measuring instrument 6 is arranged on the support structure 5 and / or the backside gas inlet assembly, which is used to detect the temperature of the wafer 3.

[0055] Based on the above structure, as shown in FIGS. 3-7, the backside gas inlet assembly provided by the embodiments of the present application includes a reflecting plate 8 and a gas inlet assembly. The reflecting plate 8 is arranged on the support structure 5 and located at the back side of the wafer 3, and the reflecting plate 8 also faces the back surface of the wafer 3 and is arranged for reflecting the radiant energy (heat) emitted by the wafer 3 to the back surface of the wafer 3. In order to improve the reflection effect, the reflecting plate 8 can be arranged parallel to the wafer 3. The gas inlet assembly is arranged on the reflecting plate 8 and is specially used for guiding the inert gas to the back surface of the wafer 3. When the wafer 3 is subjected to thermal annealing by the thermal annealing equipment, the inert gas guided to the back surface of the wafer 3 is helium (i.e., back helium ventilation). When the backside gas inlet assembly is used in other types of semiconductor equipment, the inert gas can also be other gases, such as argon. The gas inlet assembly has a gas inlet inner cavity 11 and a plurality of gas outlet holes 12, and all the gas outlet holes 12 are in communication with the gas inlet inner cavity 11. When the gas outlet holes 12 are arranged, the projections of at least part of the gas outlet holes 12 on the back surface of the wafer 3 are uniformly distributed, that is, the inert gas flowing out of the at least part of the gas outlet holes 12 is uniformly blown to the back surface of the wafer 3. In order to maximize the effect of uniform blowing, all the gas outlet holes 12 are arranged within the distribution range of the wafer 3, so that the projections of all the gas outlet holes 12 are uniformly distributed on the back surface of the wafer 3. In some embodiments, when the reflecting plate 8 is arranged parallel to the wafer 3, the gas inlet assembly arranged on the reflecting plate 8 is also arranged parallel to the wafer 3. At this time, all the gas outlet holes 12 are uniformly distributed on the gas inlet assembly (when the gas inlet assembly and the wafer 3 are not parallel, in order to ensure that the projections of the gas outlet holes 12 are uniformly distributed on the wafer 3, the arrangement positions of the gas outlet holes 12 on the gas inlet assembly will have different spacings due to the inclination of the gas inlet assembly), and the inert gas blown out of each gas outlet hole 12 is vertically blown to the back surface of the wafer 3. In the above structure, the gas inlet assembly is arranged on the reflecting plate 8. In order to reduce the influence of the gas inlet assembly on the heat reflection effect of the reflecting plate 8, the material of the gas inlet assembly is a transparent material which has little or no influence on the heat radiation, such as quartz, aluminum oxide, boron nitride, yttrium aluminum garnet, etc.

[0056] When the backside gas inlet assembly is used to ventilate the back surface of the wafer 3, the inert gas first flows into the gas inlet cavity 11. Since the gas inlet cavity 11 has a larger space relative to the inert gas supply pipeline 7, the inert gas diffuses in the gas inlet cavity 11 to reduce the gas pressure and flow rate of the inert gas, so that the inert gas blows to the wafer 3 at a smaller gas pressure and flow rate, avoiding the wafer 3 from being blown and deviated due to too large gas pressure and flow rate, improving the stability of the process and reducing the risk of wafer 3 scrap.

[0057] Further, the backside gas inlet assembly provided by the present application is provided with a flow guide structure in the gas inlet cavity 11 for guiding the inert gas to each gas outlet hole 12. Since the gas inlet cavity 11 has a relatively large space and the inert gas needs to diffuse in the gas inlet cavity 11, in order to improve the diffusion effect of the inert gas, the gas inlet cavity 11 plays a role similar to a diffuser, and the flow guide structure is arranged in the gas inlet cavity 11, so that the inert gas can better flow to each gas outlet hole 12 at different positions, further improving the uniformity of gas inlet. In addition, by arranging the flow guide structure, the inert gas can be blocked to a certain extent, so that it flows in an orderly manner according to the flow direction of the flow guide structure. In this way, the flow rate of the inert gas can be reduced, further reducing the risk of wafer 3 being blown and scrapped.

[0058] In some embodiments, the plurality of air inlet cavities 11 can also be provided, and the plurality of air inlet cavities 11 are isolated from each other, each air inlet cavity 11 has an air inlet channel 16 through which the inert gas enters the air inlet cavity 11, and each air inlet cavity 11 is in communication with the air outlet holes 12 distributed in the area where the air inlet cavity 11 is located. If the air inlet cavity 11 is provided as a larger space, the inert gas needs a longer time to diffuse in the space to achieve full diffusion (i.e. fill the air inlet cavity 11), and the air pressure and air outlet time of the air outlet holes 12 in different areas will also be different. In order to improve these situations, the larger space can be divided into a plurality of small spaces that are isolated from each other, that is, a plurality of small air inlet cavities 11 are provided in the air inlet assembly, and the air inlet cavities 11 are respectively in communication with the air outlet holes 12 in different areas. In this way, the inert gas can enter the small air inlet cavities 11 at the same time, and diffuse quickly in each small air inlet cavity 11, and then blow air to different parts of the back surface of the wafer 3 through the air outlet holes 12 in communication with the small air inlet cavities 11, thereby achieving rapid air inlet and further improving the uniformity of the air inlet. In addition, the plurality of small air inlet cavities 11 are provided, and the air inlet channel 16 is provided for each air inlet cavity 11, which can make the air inlet channel 16 more dispersedly distributed on the reflector plate 8, and will not affect the arrangement of the temperature measuring instrument 6 on the reflector plate 8, so that the structure layout of the backside air inlet assembly is more reasonable.

[0059] The air inlet assembly has an air outlet surface 13 facing the back surface of the wafer 3 (the air outlet surface 13 is the surface of the second plate body 10 facing away from the first plate body 9 described below), and in some embodiments, as shown in FIG. 6, all the air outlet holes 12 can be arranged in a plurality of straight lines on the air outlet surface 13, and the plurality of straight lines are uniformly distributed on the air outlet surface 13. In some examples, the air outlet surface 13 of the air inlet assembly is parallel to the back surface of the wafer 3, and the air outlet holes 12 are arranged in a straight line on the air outlet surface 13, and the plurality of straight lines are uniformly distributed on the air outlet surface 13, which can make the air outlet holes 12 uniformly distributed on the air outlet surface 13, thereby improving the uniformity of the air inlet. Specifically, when the air outlet holes 12 are arranged in a straight line, the plurality of straight lines can also have various arrangement modes on the air outlet surface 13, such as a cross-shaped arrangement or a grid-shaped arrangement, etc. In addition, the air outlet holes 12 can also not be arranged in a straight line, such as a circular arrangement or an array arrangement, etc. under the condition of uniform arrangement.

[0060] In some embodiments, the gas inlet assembly is made of transparent quartz material. The gas inlet assembly made of quartz material has two advantages. On the one hand, the quartz material does not affect the heat reflection of the reflection plate 8, so that the normal work of the reflection plate 8 can be ensured even if the gas inlet assembly is additionally provided on the reflection plate 8, and the process of the wafer 3 is not affected. On the other hand, the quartz material is more suitable for the working environment of the heat annealing equipment, so that the gas inlet assembly can work better, and the material of the gas inlet assembly can be the same as that of some parts (for example, the quartz light transmission plate 4) in the reaction chamber, so that the same maintenance method can be used, and the equipment maintenance is facilitated.

[0061] As shown in FIGS. 4-6, in some embodiments, the gas inlet assembly includes a first plate body 9 and a second plate body 10. The first plate body 9 covers the reflection plate 8 and is provided with a gas inlet channel 16. The second plate body 10 is stacked on the first plate body 9 and is provided with a gas outlet hole 12. The first plate body 9 and / or the second plate body 10 is provided with a groove, and the first plate body 9 and the second plate body 10 are connected by laminating to close the groove to form a gas inlet inner cavity 11. In this structure, the gas inlet assembly mainly includes two circular plate-shaped components, i.e., the first plate body 9 and the second plate body 10, and the gas inlet inner cavity 11 is formed by stacking the two plate-shaped components. This not only facilitates the processing and manufacturing, but also enables the disassembly and maintenance. The first plate body 9 and the second plate body 10 can be connected by a clamping structure, a plug-in structure, or can be bonded, or can rely on their own gravity to naturally abut. In the specific setting, since the first plate body 9 provided on the reflection plate 8 is located below the second plate body 10, and the inert gas needs to be introduced from the bottom of the reaction chamber, the gas inlet channel 16 for introducing the inert gas is provided on the first plate body 9. The gas inlet inner cavity 11 is formed by grooving the first plate body 9 and / or the second plate body 10. Specifically, the groove can be formed only on the first plate body 9, only on the second plate body 10, or on both the first plate body 9 and the second plate body 10. In order to optimize the structure, the thickness of the first plate body 9 and the second plate body 10, which respectively constitute the bottom wall and the top wall of the gas inlet inner cavity 11, can be 1-2 mm. Taking the example that the groove is formed on the second plate body 10, the top wall of the gas inlet inner cavity 11 is the part of the second plate body 10 located at the bottom of the groove, and the bottom wall of the gas inlet inner cavity 11 is the first plate body 9 itself. The distance between the top wall and the bottom wall of the gas inlet inner cavity 11 is 2±0.2 mm, and the distance between the second plate body 10 and the back surface of the wafer 3 supported by the supporting structure 1 is maintained at 2-4 mm. The selection of these numerical ranges can ensure the formation of a sustainable and stable purge gas flow on the back surface of the wafer 3, and if the wafer 3 deforms, interference with the second plate body 10 can be avoided due to the existence of the distance, so that the process can be completed smoothly.

[0062] In addition, in the above structure, the first plate body 9 covers the reflecting plate 8, and can also protect the reflecting plate 8. Specifically, after the thermal annealing device works for a period of time, it needs to be degassed, that is, to remove the residual gas or volatile substances in the reaction chamber, which can cause the coating on the surface of the reflecting plate 8 to fall off or be eroded. In addition, the thermal annealing device can also grow thin films under normal pressure. If the reaction chamber is used to grow silicon oxide films, the coating on the surface of the reflecting plate 8 will be affected, which can significantly reduce the reflecting efficiency of the reflecting plate 8 and significantly shorten the service life of the reflecting plate 8. By covering the first plate body 9 on the reflecting plate 8, the coating on the reflecting plate 8 is protected, so that the coating is not affected during degassing or thin film growth, and the coating is prevented from falling off or being eroded, thereby prolonging the service life of the reflecting plate 8, facilitating equipment maintenance, and improving the working efficiency of the reaction chamber.

[0063] As shown in FIGS. 4 and 5, a groove is formed in the surface of the second plate body 10 facing the first plate body 9, and the flow guide structure includes a protruding strip 14 protruding from the bottom wall of the groove. Specifically, the groove is formed in the second plate body 10, and the first plate body 9 below the groove is closed to form the gas inlet cavity 11 by means of the inverted groove. The protruding strip 14 is arranged in the groove, specifically, the protruding strip 14 protrudes from the bottom wall of the groove to form a flow guide wall, and the protruding strip 14 can also be a component of the second plate body 10, that is, the protruding strip 14 and the bottom wall of the groove are integrated, that is, when the groove is formed, the protruding strip 14 is not cut at the position of the protruding strip 14, and a solid part is reserved. In some embodiments, the width of the protruding strip 14 can be 2-3 mm. By arranging such a flow guide structure, the inert gas can be divided into zones and guided, and the pressure relief can be blocked, so that the whole gas inlet assembly has the effect of a diffuser, which can effectively reduce the gas inlet pressure, avoid the wafer 3 being blown off by high-pressure gas flow, and improve the yield of the product. In addition, the protruding strip 14 can also be arranged on the first plate body 9 and extend into the groove, which can also play a role in guiding and relieving pressure.

[0064] Further, as shown in FIG. 4 and FIG. 5, on the basis of the groove being opened on the surface of the second plate body 10 facing the first plate body 9, a convex ring 15 protruding relative to the bottom wall of the groove is further arranged on the bottom wall of the groove, the convex ring 15 abuts against the first plate body 9 to isolate the inner cavity of the convex ring 15 and the outer cavity of the convex ring 15, so as to form a plurality of gas inlet cavities 11. The forming mode of the convex ring 15 can be the same as that of the convex strip 14, and the width thereof can be 1 mm-2 mm. By arranging the convex ring 15 to separate the cavity of the groove into a plurality of gas inlet cavities 11, the multi-path diffusion and purging of the inert gas can be realized, which not only improves the gas inlet efficiency, but also improves the dispersion effect, so that the total pressure and total flow of the gas inlet can be improved under the conditions of avoiding the wafer 3 from being deviated and meeting the uniform gas inlet, thereby improving the cooling effect on the back surface of the wafer 3. In addition, the gas pressure and flow rate can be adjusted in different zones for different gas inlet cavities 11, which can meet the diversified cooling needs of different areas on the back surface of the wafer 3, and further significantly improve the adjustment effect of T-50.

[0065] In some embodiments, as shown in FIG. 4 and FIG. 5, a plurality of convex rings 15 are arranged in the groove in a concentric manner to form a plurality of circular and annular gas inlet cavities 11. Further, in some embodiments, the center of the convex ring 15 and the center of the groove are at the same position. By arranging the plurality of convex rings 15 in a concentric manner, the gas inlet cavities 11 located in the center region are circular cavities, and the other cavities successively surrounding the circular cavities are annular cavities. Compared with the mode in which a plurality of circular cavities are independently distributed in the groove, not only the space in the groove can be more fully utilized, but also the distribution of the gas inlet cavities 11 can be more standardized and reasonable. In addition, during the cooling process of the wafer 3, the edge of the wafer 3 often cools faster than the center. By arranging the plurality of convex rings 15 in a concentric manner to form a plurality of circular and annular cavities successively arranged in a concentric manner, the above-mentioned cooling condition often occurring in the wafer 3 can be more targetedly set and adjusted, and the cooling compensation of each area of the wafer 3 in the radial direction can be better realized, thereby further improving the cooling uniformity.

[0066] In the direction from inside to outside, the radii of the plurality of convex rings 15 arranged concentrically are sequentially incremented by equal differences, thereby radially dividing the space inside the groove, so that the space of each intake inner cavity 11 varies regularly, thereby improving the accuracy of the proportional distribution of inert gas and achieving more uniform intake. Specifically, as shown in FIGS. 4 and 5, the convex rings 15 are provided, for example, two to achieve radial trisection of the space inside the groove, the convex ring 15 located on the inner side of the two convex rings 15 separates a circular central intake inner cavity 17, the convex ring 15 located on the outer side of the two convex rings 15 and the convex ring 15 located on the inner side separate an annular intermediate intake inner cavity 18, and the convex ring 15 located on the outer side and the side wall 19 of the groove (this side wall 19 is located at the circumferential edge of the circular second plate body 10 and forms an annular side wall) separate an annular outer intake inner cavity 20. Alternatively, the radii of the plurality of convex rings 15 can not be sequentially incremented by equal differences, that is, the space of each intake inner cavity 11 can not vary regularly, but the flow controller 22 described below is used to make the intake amount of each intake inner cavity 11 different, so as to achieve the purpose of uniformly blowing the wafer 3.

[0067] On the basis of the plurality of convex rings 15 arranged concentrically separating to form a plurality of circular and annular intake inner cavities 11, each intake inner cavity 11 is also provided with an intake passage 16, and as shown in FIG. 5: the circular intake inner cavity 11 is the central intake inner cavity 17 located in the central region of the second plate body 10, which is separated by the innermost convex ring 15 of the plurality of convex rings 15 in the central region of the second plate body 10, and when the intake passage 16 is provided in the central intake inner cavity 17, the intake passage 16 of the central intake inner cavity 17 is located at the center of the central intake inner cavity 17, which is closer to the gas outlet holes 12 connected by the central intake inner cavity 17, so that the flow path of the low-temperature inert gas through the intake passage 16 at this position, the central intake inner cavity 17 and the gas outlet holes 12 is shorter, thereby blowing faster to the central position of the wafer 3. Since the temperature of the central position of the wafer 3 is higher during heating, the wafer 3 can be better cooled.

[0068] The plurality of annular gas inlet cavities 11 comprises a central gas inlet cavity 17, an intermediate gas inlet cavity 18 and an outer gas inlet cavity 20 which are arranged in sequence and surround the central gas inlet cavity 17. According to the position of the annular gas inlet cavity 11, the outer gas inlet cavity 20 is the largest diameter gas inlet cavity located at the circumferential edge of the second plate body 10, and the intermediate gas inlet cavity 18 is the gas inlet cavity located between the central gas inlet cavity 17 and the outer gas inlet cavity 20. The gas inlet passage 16 arranged by the outer gas inlet cavity 20 is arranged close to the outer side edge (the outer side edge refers to the circumferential edge with larger diameter in the annular structure) of the outer gas inlet cavity 20. Since the space of the outer gas inlet cavity 20 is larger, the gas inlet passage 16 arranged in this way can more fully cool the edge part of the wafer. The gas inlet passage 16 arranged by the intermediate gas inlet cavity 18 is arranged close to the inner side edge (the inner side edge refers to the circumferential edge with smaller diameter in the annular structure) of the intermediate gas inlet cavity 18. In this way, the gas inlet passage 16 can be as close as possible to the high temperature area in the center of the wafer 3, so that the inert gas can be more fully distributed in the center and the surrounding area of the wafer 3, thereby better cooling the center and the surrounding area of the wafer 3 and better ensuring the temperature uniformity of each part of the wafer 3. It should be noted that in the above embodiment, the intermediate gas inlet cavity 18 is one, but the embodiments of the present application are not limited thereto. In actual application, the intermediate gas inlet cavity 18 can also be multiple and arranged concentrically, and each intermediate gas inlet cavity 18 is provided with a gas inlet passage 16.

[0069] On the basis of having multiple air inlet inner cavities 11, each air inlet inner cavity 11 has one air inlet channel 16 in the embodiment shown in FIG. 4, but the application is not limited thereto. In another embodiment shown in FIG. 5, the application also makes at least one air inlet inner cavity 11 have multiple air inlet channels 16, i.e., all the air inlet inner cavities 11 can have multiple air inlet channels 16, or a part of the air inlet inner cavities 11 have multiple air inlet channels 16, and the rest of the air inlet inner cavities 11 have one air inlet channel 16. Moreover, the multiple air inlet channels 16 communicating with the same air inlet inner cavity 11 are arranged symmetrically about the center of the convex ring 15, so that the inert gas can enter each air inlet inner cavity 11 more uniformly, which is beneficial to the rapid and uniform diffusion of the inert gas in each air inlet inner cavity 11. As shown in FIG. 5 and FIG. 7, in the specific arrangement, a total of 5-10 air inlet channels 16 can be configured to ensure good uniform air inlet effect. As shown in FIG. 5, the air inlet channels 16 arranged in the outer air inlet inner cavities 20 are two, and the air inlet channels 16 arranged in the middle air inlet inner cavities 18 are also two. Further, the connecting line of the two air inlet channels 16 arranged in the outer air inlet inner cavities 20 can pass through the center of the groove, and the connecting line of the two air inlet channels 16 arranged in the middle air inlet inner cavities 18 can also pass through the center of the groove, but has an included angle with the connecting line of the two air inlet channels 16 in the outer air inlet inner cavities 20. The air inlet channel 16 arranged in the center air inlet inner cavity 17 is one and arranged at the center of the groove, or the air inlet channel 16 in the center air inlet inner cavity 17 can also be arranged with two and the connecting line passes through the center of the groove, and has an included angle with the other two connecting lines. Specifically, the inner hole diameter of the air inlet channel 16 is 4-6 mm.

[0070] In addition, when there is only one air inlet inner cavity 11 with relatively large space, multiple air inlet channels 16 can also be arranged, and the communication parts of these air inlet channels 16 with the air inlet inner cavity 11 are uniformly distributed relative to the air inlet inner cavity 11.

[0071] As shown in FIG. 4 and FIG. 7, the air inlet channel 16 is arranged protruding on the first plate body 9 in the direction away from the second plate body 10 and passes through the reflecting plate 8. The air inlet channel 16 is arranged vertically on the surface of the first plate body 9 facing away from the second plate body 10. Since the reflecting plate 8 is located below the first plate body 9, the air inlet channel 16 passes through the reflecting plate 8, and in order to improve the firmness of the air inlet assembly on the reflecting plate 8, the air inlet channel 16 is also connected with the reflecting plate 8 when passing through the reflecting plate 8, for example, the tubular air inlet channel 16 is interference fit with the through hole 24 (the number of through holes 24 and the distribution mode on the reflecting plate 8 are the same as the number of air inlet channels 16 and the distribution mode on the first plate body 9) on the reflecting plate 8 for the air inlet channel 16 to pass through, or a positioning structure is arranged between the air inlet channel 16 and the reflecting plate 8.

[0072] When a plurality of intake inner cavities 11 are provided, the gas supply pipeline 7 for supplying inert gas includes a plurality of sub-pipelines 21 in communication with different intake passages 16, and each sub-pipeline 21 is provided with a flow controller 22. As shown in FIG. 4, corresponding to the central intake inner cavity 17, the intermediate intake inner cavity 18 and the outer intake inner cavity 20, the gas supply pipeline 7 includes three sub-pipelines 21 in communication with the intake passages 16 thereof, respectively, and each of the three sub-pipelines 21 is provided with a flow controller 22 to adjust and distribute the intake amount of the three intake inner cavities 11, so that the intake assembly can target the back surface of the wafer 3 for cooling according to the heat dissipation of the wafer 3, thereby improving the working performance of the backside intake assembly provided in the present application.

[0073] As shown in FIG. 6, the surface of the second plate body 10 facing away from the first plate body 9 is the gas outlet surface 13, and the plurality of straight lines formed by the arrangement of the gas outlet holes 12 on the gas outlet surface 13 all pass through the center of the gas outlet surface 13, and the included angle between any two adjacent straight lines is equal, so that the gas outlet holes 12 are distributed in a straight line from the center to the edge of the second plate body 10. For example, 2 straight lines can be arranged in a cross shape, or 4 straight lines can be arranged in a horizontal character shape, etc.

[0074] Further, as shown in FIG. 5, on each straight line, the hole spacing between any two adjacent gas outlet holes 12 is the same, and the hole spacing of all straight lines is the same, so that all gas outlet holes 12 are distributed on a plurality of concentric circles around the center of the gas outlet surface 13. By such arrangement, the gas outlet holes 12 can be further uniformly distributed, and the back surface of the wafer 3 can be further uniformly swept. Specifically, the hole diameter of the gas outlet hole 12 can be 2-3 mm, and 5-10 gas outlet holes 12 can be arranged on each straight line within the radius of the second plate body 10, and a total of 40-80 gas outlet holes 12 can be arranged, 7 gas outlet holes 12 can be arranged on each straight line within the radius of the second plate body 10, and a total of 56 (7*8=56) gas outlet holes 12 can be arranged. In the related art, the T-50 has a narrow adjustment window, and there is a bottleneck in the cooling rate, which cannot stably achieve the effect of uniformly cooling the wafer 3. When the helium flow rate exceeds 1.5 slm, the cooling rate will not be improved, and the demand for shorter high temperature interval (T-50) under advanced process cannot be met. In the present application, by arranging the intake inner cavities 11 in the above manner, and uniformly arranging the above gas outlet holes 12 and selecting the above arrangement quantity, the demand for T-50 can be better met, and the problem of slow cooling rate is solved.

[0075] When all the gas outlet holes 12 are distributed on a plurality of concentric circles around the center of the gas outlet surface 13, as shown in FIG. 5, a plurality of arc-shaped protrusions 14 enclose a flow guide ring having radial openings 23, the flow guide rings are arranged concentrically, and each flow guide ring at least encloses a plurality of gas outlet holes 12 located on the same circle, and all the flow guide rings form a flow guide structure. The arc-shaped protrusions 14 and the annular distribution avoid the existence of dead angles, can better guide the flow of inert gas, and the uniform dispersion effect of the gas is better. The radial openings 23 are channels for the radial diffusion of inert gas between the flow guide rings. In addition, the protrusions 14 can also be arranged in other structures, for example, the protrusions 14 are linear, two protrusions 14 form a group, and the extension direction of each group is the same as the extension direction of each straight line formed by the arrangement of the gas outlet holes 12, and the two protrusions 14 in the same group are arranged on both sides of a straight line, thereby forming a radially extending flow guide gap, and each gas outlet hole 12 located on a straight line is located in the gap, that is, the flow guide structure is also cross-shaped or H-shaped, which can also have a good flow guide effect.

[0076] Based on the above-mentioned backside gas inlet assembly, the application further provides a thermal annealing apparatus comprising the above-mentioned backside gas inlet assembly for the thermal annealing apparatus. The thermal annealing apparatus has the beneficial effects brought by the backside gas inlet assembly. Please refer to the above description, which will not be repeated here.

[0077] The above describes the basic principles of the application in combination with specific embodiments. However, it should be pointed out that the advantages, advantages, effects and the like mentioned in the application are only examples and cannot be considered as mandatory for each embodiment of the application. In addition, the above-mentioned specific details are only for the purpose of example and understanding, and the application is not limited to the above-mentioned specific details.

[0078] The block diagrams of the devices, apparatuses, equipment and systems involved in the application are only illustrative examples and are not intended to require or imply the connection, arrangement and configuration shown in the block diagrams. As those skilled in the art will recognize, these devices, apparatuses, equipment and systems can be connected, arranged and configured in any way. Words such as "include", "contain", "have" and the like are open-ended words, which mean "including but not limited to", and can be used interchangeably. The words "or" and "and" used herein mean the word "and / or", and can be used interchangeably unless the context clearly indicates otherwise. The word "such as" used herein means the phrase "such as but not limited to", and can be used interchangeably.

[0079] It should also be noted that in the devices, apparatuses and methods of the application, each component or step can be decomposed and / or recombined. These decompositions and / or recombinations should be considered as equivalent solutions of the application.

[0080] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein can be applied to other aspects without departing from the scope of the application. Thus, the present application is not intended to be limited to the aspects shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0081] It should be understood that the adjectives "first", "second", "third", "fourth", "fifth", and "sixth" as used in the embodiments description of the present application are used only to more clearly recite the technical solutions, and cannot be used to limit the protection scope of the present application.

[0082] The above description has been presented for the purpose of illustration and description. Furthermore, this description is not intended to limit the embodiments of the application to the forms disclosed herein. Although several example aspects and embodiments have been discussed above, those of ordinary skill in the art will appreciate a variety of modifications, alternatives, permutations, additions, and sub-combinations of the described aspects and embodiments.

Claims

1. A backside gas inlet assembly for a thermal anneal apparatus, comprising: A gas supply device for supplying inert gas to the back surface of a wafer located in a reaction chamber, comprising: a reflecting plate for reflecting the radiant energy emitted by the wafer to the back surface of the wafer; a gas inlet assembly made of transparent material and arranged on the reflecting plate, having a gas inlet cavity and gas outlet holes, the gas outlet holes being in communication with the gas inlet cavity; wherein the inert gas entering the gas inlet cavity is dispersed in the gas inlet cavity and then flows to the back surface of the wafer through the gas outlet holes.

2. The backside gas inlet assembly for a thermal anneal apparatus of claim 1, wherein, The gas outlet holes are arranged in multiple and are respectively used to guide the inert gas to different parts of the back surface of the wafer. The gas inlet cavity is provided with a flow guide structure for guiding the inert gas to each gas outlet hole.

3. The backside gas inlet assembly for a thermal anneal apparatus of claim 1, wherein, The gas inlet cavity has multiple and is isolated from each other, each gas inlet cavity has a gas inlet channel, and the gas outlet holes are arranged in multiple, and each gas inlet cavity is in communication with the gas outlet holes distributed in the area where the gas inlet cavity is located.

4. The backside gas inlet assembly for a thermal anneal apparatus of claim 1, wherein, The gas inlet assembly has a gas outlet surface facing the back surface of the wafer. All the gas outlet holes are arranged in multiple straight lines on the gas outlet surface, and the multiple straight lines are uniformly distributed on the gas outlet surface.

5. Backside gas inlet assembly for a thermal annealing apparatus according to any of claims 1-4, characterized in that, The gas inlet assembly comprises: a first plate body covering the reflecting plate and provided with a gas inlet channel; a second plate body arranged on the first plate body and provided with the gas outlet holes; wherein the first plate body and / or the second plate body is provided with a groove, and the first plate body and the second plate body are laminated to close the groove to form the gas inlet cavity.

6. The backside gas inlet assembly for a thermal anneal apparatus of claim 5, wherein, The groove is arranged on the surface of the second plate body facing the first plate body. The gas inlet cavity is provided with a flow guide structure, the flow guide structure comprises an arc-shaped protruding strip in the groove and protruding relative to the bottom wall of the groove, and multiple protruding strips form a flow guide ring with a radial opening, and the flow guide ring has multiple concentrically arranged.

7. The backside gas inlet assembly for a thermal anneal apparatus of claim 5, wherein, The groove is arranged on the surface of the second plate body facing the first plate body, and the bottom wall of the groove is provided with a convex ring protruding relative to the bottom wall, and the convex ring is in abutment with the first plate body to isolate the inner and outer groove cavities of the convex ring to form multiple gas inlet cavities.

8. The backside gas inlet assembly for a thermal anneal apparatus of claim 7, wherein, Multiple concentric convex rings are arranged in the groove to form a circular gas inlet cavity and multiple annular gas inlet cavities.

9. The backside gas inlet assembly for a thermal anneal apparatus of claim 8, wherein, Each gas inlet cavity is provided with a gas inlet channel, and: The circular gas inlet cavity is a central gas inlet cavity located in the central region of the second plate body, and the gas inlet channel of the central gas inlet cavity is located at the center of the central gas inlet cavity; The multiple annular gas inlet cavities include a middle gas inlet cavity and an outer gas inlet cavity which are sequentially arranged around the central gas inlet cavity, and the gas inlet channel of the outer gas inlet cavity is arranged close to the outer edge of the outer gas inlet cavity; and the gas inlet channel of the middle gas inlet cavity is arranged close to the inner edge of the middle gas inlet cavity.

10. Backside gas inlet assembly for a thermal annealing apparatus according to claim 7 or 8, characterized in that At least one gas inlet cavity has multiple gas inlet channels, and the multiple gas inlet channels in communication with the same gas inlet cavity are arranged symmetrically about the center of the convex ring.

11. The backside gas inlet assembly for a thermal anneal apparatus of claim 8, wherein, The gas supply pipeline for supplying the inert gas comprises a plurality of sub-pipelines in communication with different gas inlet channels, and each of the sub-pipelines is provided with a flow controller.

12. The backside gas inlet assembly for a thermal anneal apparatus of claim 5, wherein, The gas inlet channels are arranged protruding on the first plate body away from the second plate body and penetrating through the reflecting plate.

13. The backside gas inlet assembly for a thermal anneal apparatus of claim 5, wherein, The surface of the second plate body facing away from the first plate body is an air outlet surface, the air outlet holes are arranged in multiple straight lines on the air outlet surface, the multiple straight lines all pass through the center of the air outlet surface, and the included angles between any two adjacent straight lines are equal.

14. A thermal annealing apparatus, characterized by, A backside gas inlet assembly for a thermal annealing apparatus according to any one of claims 1-13.

15. The thermal anneal apparatus of claim 14, wherein, Further comprising: a reaction chamber; a carrying structure arranged in the reaction chamber, having a carrying surface for carrying a wafer, and capable of driving the wafer to rotate; a heating light source arranged above the carrying structure, for providing heat required by the wafer; a quartz light-transmitting plate arranged between the heating light source and the carrying structure, for isolating the heating light source and the carrying structure and allowing heat generated by the heating light source to pass through; a supporting structure for supporting the backside gas inlet assembly and making the top surface of the backside gas inlet assembly below the carrying surface for carrying the wafer; a temperature detector arranged on the supporting structure and / or the backside gas inlet assembly, for detecting the temperature of the wafer.

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