Pre-cleaning device and semiconductor equipment

Abstract

The utility model provides a pre-cleaning device and semiconductor equipment. Wherein the temperature compensation assembly is additionally arranged in the pre-cleaning device. And the temperature compensation assembly is used for performing temperature compensation on the edge area of the wafer. Furthermore, the temperature compensation assembly comprises a resistance wire and / or a heating lamp. And the resistance wire performs compensation heating on the etching agent sprayed on the edge area of the wafer so as to compensate the reaction temperature of the edge area of the wafer. And the heating lamp can directly irradiate the edge area of the wafer to carry out temperature compensation on the edge area, and the reaction temperature difference between the center area and the edge area of the wafer can be reduced through the heating lamp and the edge area, so that the problem that a reaction byproduct film layer is not uniform due to the temperature difference is avoided, and the yield of the wafer is improved. Therefore, the etching amount of each area of the wafer can be balanced, so that the pre-cleaning effect is improved, and the surface of the pre-cleaned wafer is ensured to have better uniformity.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductor manufacturing, and particularly relates to a pre-cleaning device and a semiconductor device. Background Art

[0002] Epitaxy (EPI) is a process of growing a single crystal thin film with a certain thickness, resistance value, and type that has the same lattice arrangement as the substrate along the substrate crystal orientation. In the actual process, to ensure the film quality of the epitaxial layer, a pre-cleaning process is usually performed before epitaxial growth to remove the natural oxide layer formed on the wafer surface. Currently, the following two pre-cleaning methods are commonly used in the prior art: The first is to use the SiCoNi etching process to etch and remove the silicon dioxide layer on the wafer surface. That is, a mixed gas of NF3 and NH3 is excited by a plasma generating device to be converted into ammonium fluoride NH4F and ammonium bifluoride NH4F·HF as the etchant; then the etchant is sprayed onto the wafer surface to react to form a solid by-product of hexafluorosilazane (NH4)2SiF6; finally, the reaction by-product is sublimated by annealing to achieve the removal of the silicon dioxide layer. Among them, the specific reaction equation of the SiCoNi etching process is as follows:

[0003] NF3 + NH3 → NH4F + NH4F·HF;

[0004] NH4F + SiO2 → (NH4)2SiF6 + H2O;

[0005] (NH4)2SiF6 → SiF4 + NH3 + HF.

[0006] The second is to use the Atomic Layer Clean (ALC) process to etch and remove the silicon dioxide layer on the wafer surface. That is, HF and NH3 are used as etchants to react with the silicon dioxide layer on the wafer surface to form a solid by-product of hexafluorosilazane (NH4)2SiF6; similarly, the reaction by-product is sublimated by annealing to achieve the removal of the silicon dioxide layer. Among them, the specific reaction equation of the ALC process is as follows:

[0007] HF + NH3 + SiO2 → (NH4)2SiF6 + H2O;

[0008] (NH4)2SiF6 → SiF4 + NH3 + HF.

[0009] Therefore, it can be seen from the above two pre-cleaning processes that the formation thickness of the reaction by-products will directly affect the etching amount of the etching process. However, since the adsorption of NH3 is extremely susceptible to temperature, when the temperature is lower, the adsorption amount of the wafer to NH3 is larger, and the thickness of the reaction by-products is larger. And based on the existing pre-cleaning device, there is a certain temperature difference between the central region and the edge region of the wafer during the reaction process, which results in a thinner middle and thicker edges of the reaction by-product film layer formed on the wafer surface, thereby affecting the overall thermal conductivity of the reaction by-product film layer. And during the subsequent high-temperature sublimation process, it will cause the problem that the etching amount of the edge region of the wafer is greater than that of the central region of the wafer, which not only affects the removal effect of the natural oxide layer but also affects the etching uniformity.

[0010] Therefore, there is an urgent need for a new pre-cleaning device to solve the above technical problems. Summary of the Invention

[0011] The purpose of the present invention is to provide a pre-cleaning device and a semiconductor device to solve at least one of the problems of how to improve the uniformity of the reaction by-product film layer in the pre-cleaning process and how to improve the pre-cleaning process effect.

[0012] To solve the above technical problems, the present invention provides a pre-cleaning device, including: a reaction unit and a supply unit;

[0013] The reaction unit includes a reaction chamber, a carrier table, a heat source, and a heat compensation component; wherein, the carrier table, the heat source, and the heat compensation component are all accommodated in the reaction chamber; the carrier table is used to carry the wafer; the heat source is used to heat the inside of the reaction chamber; the heat compensation component is disposed opposite to the edge region of the wafer to heat at least the edge region of the wafer;

[0014] The supply unit is connected to the reaction chamber and is used to provide an etchant into the reaction chamber to remove a part of the thickness of the wafer.

[0015] Optionally, in the pre-cleaning device, the heat compensation component includes a resistance wire and / or a heating lamp.

[0016] Optionally, in the pre-cleaning device, the reaction unit further includes a spray head; the spray head is disposed above the wafer, and the spray head has a spraying surface and an inlet port. The spraying surface is disposed opposite to the surface of the wafer, and the inlet port is connected to the supply unit, so that the etchant provided by the supply unit enters the spray head through the inlet port and is sprayed onto the wafer surface through the spraying surface;

[0017] Among them, the thermal compensation component includes a resistance wire, the resistance wire is arranged inside the nozzle, and is arranged around the edge of the nozzle to at least heat the etchant sprayed out from the edge of the nozzle.

[0018] Optionally, in the pre-cleaning device, the distance between the resistance wire and the edge of the nozzle ranges from 3 cm to 5 cm.

[0019] Optionally, in the pre-cleaning device, a heating coil is arranged inside the nozzle; the heating coil is distributed inside the loop of the resistance wire and is arranged at an interval from the resistance wire.

[0020] Optionally, in the pre-cleaning device, the distance between the heating coil and the edge of the nozzle ranges from 10 cm to 15 cm.

[0021] Optionally, in the pre-cleaning device, the process of removing a part of the thickness of the wafer sequentially includes a reaction stage and a sublimation stage, and in the reaction stage, the temperature range of the resistance wire is: 180°C to 190°C; in the sublimation stage, the temperature range of the resistance wire is 190°C to 200°C.

[0022] Optionally, in the pre-cleaning device, the thermal compensation component includes a plurality of heating lamps, and the plurality of heating lamps are arranged above the wafer and are arranged relative to the edge area of the wafer.

[0023] Optionally, in the pre-cleaning device, the process of removing a part of the thickness of the wafer sequentially includes a reaction stage and a sublimation stage; and in the sublimation stage, the temperature range of the heating lamp is 190°C to 200°C.

[0024] Based on the same concept, this embodiment provides a semiconductor device including the pre-cleaning device.

[0025] In summary, the present invention provides a pre-cleaning device and a semiconductor device. Among them, a temperature compensation component is added to the pre-cleaning device. The temperature compensation component is used to perform temperature compensation on the edge area of the wafer. Further, the temperature compensation component includes a resistance wire and / or a heating lamp. The resistance wire compensates and heats the etchant sprayed on the edge area of the wafer, thereby realizing the compensation of the reaction temperature of the edge area of the wafer. And, the heating lamp can directly irradiate the edge area of the wafer to perform temperature compensation on it. Both can reduce the reaction temperature difference between the central area and the edge area of the wafer, thereby avoiding the problem of uneven reaction by-product film layers caused by the temperature difference, being beneficial to balancing the etching amount of each area of the wafer, thereby improving the pre-cleaning effect and ensuring that the surface of the wafer after pre-cleaning has better uniformity. Brief Description of the Drawings

[0026] Those of ordinary skill in the art will understand that the provided drawings are used to better understand the present utility model and do not constitute any limitation to the scope of the present utility model.

[0027] Figure 1 It is a schematic structural diagram of the pre-cleaning device in an embodiment of the present utility model.

[0028] Figure 2 It is a schematic distribution diagram of the heating wire in an embodiment of the present utility model.

[0029] Figure 3 It is a schematic diagram of the distribution size relationship of the heating wire in an embodiment of the present utility model.

[0030] Figure 4 It is a schematic distribution diagram of the heating wire and the heating lamp in an embodiment of the present utility model.

[0031] Figure 5 It is a schematic structural diagram in the sublimation stage in an embodiment of the present utility model.

[0032] And, in the drawings:

[0033] 10 - reaction unit; 101 - reaction chamber; 102 - carrier; 103 - cooling plate; 104 - nozzle; 104a - spraying surface; 104b - inlet port; 105 - heating wire; 106 - heating lamp; 20 - supply unit; L1 - distance between the heating wire and the edge of the nozzle; L2 - distance between the heating coil and the edge of the nozzle; W - wafer. Detailed Description of the Embodiments

[0034] To make the objectives, advantages, and features of the present utility model clearer, the following further describes the present utility model in detail with reference to the drawings and specific embodiments. It should be noted that the drawings are all in a very simplified form and not drawn to scale, and are only used to conveniently and clearly assist in explaining the objectives of the embodiments of the present utility model. In addition, the structures shown in the drawings are often part of the actual structures. In particular, the emphasis to be shown in each drawing is different, and sometimes different scales are used. It should also be understood that unless otherwise specifically stated or indicated, the terms "first", "second", "third", etc. in the description of the specification are only used to distinguish the various components, elements, steps, etc. in the specification, rather than to represent the logical relationship or sequential relationship, etc. between the various components, elements, steps. And, the X-axis direction, Y-axis direction, and Z-axis direction referred to in the specification of the present application are three mutually perpendicular directions in three-dimensional space.

[0035] Please refer to Figure 1, this embodiment provides a pre-cleaning device, including: a reaction unit 10 and a supply unit 20; the reaction unit 10 includes a reaction chamber 101, a carrier table 102, a heat source, and a heat compensation component; wherein, the carrier table 102, the heat source, and the heat compensation component are all accommodated in the reaction chamber 101; the carrier table 102 is used to carry the wafer W; the heat source is used to heat the inside of the reaction chamber 101; the heat compensation component is disposed opposite to the edge region of the wafer W to heat at least the edge region of the wafer W; the supply unit 20 is connected to the reaction chamber 101 and is used to supply an etchant into the reaction chamber 101 to remove a part of the thickness of the wafer W.

[0036] It can be seen that the pre-cleaning device provided in this embodiment is additionally provided with the temperature compensation component for performing temperature compensation on the edge region of the wafer W, thereby avoiding the problem of uneven reaction by-product film layers caused by temperature differences, being beneficial to balancing the etching amounts of each region of the wafer W, improving the pre-cleaning effect, and ensuring that the surface of the wafer W after pre-cleaning has better uniformity.

[0037] The following specifically describes the pre-cleaning device provided in this embodiment in conjunction with the attached Figures 1 to 5 drawings.

[0038] Please continue to refer to Figure 1 , the pre-cleaning device provided in this embodiment is used to remove the film layer to be removed on the surface of the wafer W through an etching process. Optionally, the SiCoNi etching process or the ALC process is adopted. Specifically, the pre-cleaning device includes: a reaction unit 10 and a supply unit 20. The reaction unit 10 is used to provide the environment and space required for the etching reaction; the supply unit 20 is used to provide the etchant. Among them, according to different reaction requirements, the types of the etchant are different, and the etchant can be liquid and / or gaseous. Exemplarily, in the SiCoNi etching process, the supply unit 20 includes a plasma generator to generate the etchants required for the reaction: NH4F and NH4F·HF. Or, in the ALC process, the etchants provided by the supply unit 20 include HF and NH3.

[0039] Further, the reaction unit 10 includes a reaction chamber 101, a carrier stage 102, a cooling plate 103, a nozzle 104, a heat source (not shown), and a thermal compensation component. Among them, the carrier stage 102, the cooling plate 103, the nozzle 104, the heat source, and the thermal compensation component are all accommodated in the reaction chamber 101. The reaction chamber 101 is used to provide the environmental conditions and space required for the reaction. The carrier stage 102 is disposed at the bottom of the reaction chamber 101 for carrying the wafer W and moving the wafer W at least in the Z-axis direction. The cooling plate 103 is disposed below the carrier stage 102 and contacts or is close to the carrier stage 102. The cooling plate 103 is used to effectively reduce or control the temperature of the carrier stage 102 and the wafer W during the reaction, which is beneficial to the formation of solid reaction by-products, and at the same time can avoid damage to the wafer W due to excessive temperature during the reaction. And, the nozzle 104 is disposed above the carrier stage 102, that is, opposite to the wafer W. The nozzle 104 has a spraying surface 104a and an inlet port 104b. The spraying surface 104a is disposed opposite to the surface of the wafer W, and the spraying surface 104a has a plurality of through holes and is connected to the environment inside the reaction chamber 101. The inlet port 104b is connected to the supply unit 20 so that the etchant provided by the supply unit 20 enters the nozzle 104 through the inlet port 104b and is sprayed onto the surface of the wafer W through each of the through holes in the spraying surface 104a. Preferably, the plurality of through holes are uniformly distributed on the spraying surface 104a so that the etchant is uniformly sprayed onto the surface of the wafer W, improving the uniformity of the reaction. And, the heat source is disposed near the upper part of the reaction chamber 101 for heating the environment inside the reaction chamber 101 to provide the temperature required for the reaction stage and the sublimation stage. Optionally, the heating type of the heat source includes but is not limited to electric heating, radio frequency heating, laser heating, or induction heating.

[0040] Further, during the pre-cleaning etching reaction process, the temperature of the central region of the wafer W is higher than that of the edge region, so the thickness of the reaction by-product film layer formed is thinner in the central region and thicker in the edge region. In this regard, the pre-cleaning device provided in this embodiment is provided with the thermal compensation component in the reaction unit 10. The thermal compensation component is disposed opposite to the edge region of the wafer W to at least heat the edge region of the wafer W, thereby alleviating the temperature difference between the central region and the edge region of the surface of the wafer W, improving the uniformity of the reaction by-product film layer, and further ensuring the balance of the etching amount in each region of the wafer W.

[0041] Preferably, the thermal compensation component includes a heating wire 105 and / or a heating lamp 106. That is, both the heating wire 105 and the heating lamp 106 can be provided in the reaction unit 10, or either one can be selected. In one example, as Figure 1 and Figure 2 shown, the thermal compensation component includes a heating wire 105. The heating wire 105 is disposed in the nozzle 104, near the spraying surface 104a, and is arranged around the edge of the spraying surface 104a to heat the etchant flowing out of each through hole near the edge of the spraying surface 104a. After being heated by the heating wire 105, the etchant will be sprayed toward the edge region of the wafer W, thereby achieving temperature compensation for the edge region of the wafer W. Further, as Figure 2 shown, the nozzle 104 also has its own heating coil 1041 for heating the etchant. And preferably, the heating coils 1041 are evenly distributed within the loop of the heating wire 105, that is, near the central region of the nozzle 104. And the heating coils 1041 and the heating wire 105 are spaced apart to avoid interference during the heating process. Based on this, by combining the heating coils 1041 and the heating wire 105, the temperature uniformity of the etchant sprayed from the nozzle 104 can be further improved, which is beneficial to achieving uniform reactions in each region of the wafer W surface. Herein, the specific model and the number of turns of the heating wire 105 are not limited in this embodiment, and it can be one turn or several turns. And, preferably, as Figure 3 shown, the distance L1 between the heating wire 105 and the edge of the nozzle 104 ranges from 3 cm to 5 cm; for example, 3 cm, 4 cm, or 5 cm. The distance L2 between the heating coils 1041 and the edge of the nozzle 104 ranges from 10 cm to 15 cm; for example, 10 cm, 12 cm, or 15 cm.

[0042] In another example, as Figure 1 and Figure 4As shown, the resistance wire 105 and the heating lamp 106 are both arranged inside the reaction unit 10. The resistance wire 105 is arranged near the edge of the nozzle 104 to heat the etchant ejected from the edge of the nozzle 104. The heating lamp 106 is arranged above the wafer W and is arranged relative to the edge area of the wafer W. That is, the heating lamp 106 directly heats the edge area of the wafer W to alleviate the temperature difference between the central area and the edge area of the wafer W, thereby improving the uniformity of the reaction by-product film layer and ensuring the balanced etching amount in each area of the wafer W. Similarly, in this example, the specific model and quantity of the heating lamp 106 are not limited either. It is preferable to arrange a plurality of heating lamps 106, and each heating lamp 106 is evenly distributed around the edge of the wafer W to enable balanced temperature compensation for the edge area of the wafer W. Among them, the heating lamp 106 is a beam-type heat source, such as a laser. In other examples, the thermal compensation component only includes the heating lamp 106, and this embodiment will not elaborate on this anymore.

[0043] It should be noted that during the SiCoNi etching process or the ALC etching process, it successively includes a reaction stage and a sublimation stage. Specifically, please refer to Figure 1 , in the reaction stage, the supply unit 20 supplies the etchant required for the reaction into the nozzle 104. Preferably, the etchant is evenly sprayed onto the surface of the wafer W after being heated by the resistance wire 105 and the heating coil 1041 inside the nozzle 104 to ensure the balanced reaction temperature at each part of the surface of the wafer W. Among them, the temperature range of the resistance wire 105 is: 180°C to 190°C; for example, it is 180°C. And based on the temperature control effect of the cooling plate 103, a solid reaction by-product layer is generated by the reaction between the surface of the wafer W and the etchant, realizing the modification of the film layer to be removed on the surface of the wafer W. And when the reaction lasts for a set time, the supply unit 20 stops supplying the etchant; the reaction stage ends and it is necessary to enter the sublimation stage. The sublimation stage is used to achieve in-situ annealing so that the reaction by-products attached to the surface of the wafer W are sublimated at high temperature, thereby realizing the removal of the film layer to be removed on the surface of the wafer W.

[0044] Based on this, as Figure 5As shown, after completing the reaction stage, the carrier stage 102 drives the wafer W to rise along the positive half-axis direction of the Z axis, bringing the wafer W closer to the nozzle 104, ensuring that the wafer W quickly enters the high-temperature environment, which is conducive to implementing the high-temperature annealing process. At the same time, before officially entering the sublimation stage, the temperature of the heating wire 105 needs to be adjusted to 190°C to 200°C; and / or, the temperature of the heating lamp 106 is also adjusted to 190°C to 200°C; for example, it is 190°C, 195°C or 200°C. And, during the sublimation stage, the temperature of the heating wire 105 and / or the heating lamp 106 is always maintained at 190°C to 200°C. Therefore, while the heat source is heating, the compensating heating of the heating wire 105 and / or the heating lamp 106 can more efficiently achieve the high-temperature sublimation of the solid reaction by-product layer, and then achieve the removal of the film layer to be removed on the surface of the wafer W. Among them, the reaction unit 10 further includes an air extraction module (not shown). And during the sublimation stage, the air extraction module quickly discharges the gas formed by sublimation from the reaction chamber 101, avoiding gas residue from affecting the cleaning effect.

[0045] Based on the same concept, this embodiment further provides a semiconductor device. The semiconductor device includes the pre-cleaning device described above.

[0046] In summary, in the pre-cleaning device and the semiconductor device provided in this embodiment, the temperature compensation component is added to perform temperature compensation on the edge region of the wafer W. Further, the temperature compensation component includes a heating wire 105 and / or a heating lamp 106. The heating wire 105 compensates for the heating of the etchant sprayed on the edge region of the wafer W, thereby achieving the compensation of the reaction temperature of the edge region of the wafer W. And, the heating lamp 106 can directly irradiate the edge region of the wafer W to perform temperature compensation on it, both of which can reduce the reaction temperature difference between the central region and the edge region of the wafer W, and then avoid the problem of uneven reaction by-product film layer caused by the temperature difference, which is beneficial to balancing the etching amount of each region of the wafer W, thereby improving the pre-cleaning effect and ensuring that the surface of the wafer W after pre-cleaning has better uniformity.

[0047] In addition, it should also be recognized that although the present utility model has been disclosed above with preferred embodiments, the above embodiments are not intended to limit the present utility model. For any person skilled in the art, without departing from the scope of the technical solution of the present utility model, many possible changes and modifications can be made to the technical solution of the present utility model by using the technical content disclosed above, or it can be modified into equivalent embodiments with equivalent changes. Therefore, all content that does not depart from the technical solution of the present utility model, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present utility model still belong to the scope protected by the technical solution of the present utility model.

Claims

1. A pre-cleaning device, characterized in that, Comprising: A reaction unit and a supply unit; The reaction unit includes a reaction chamber, a carrier stage, a heat source, and a thermal compensation component; wherein, the carrier stage, the heat source, and the thermal compensation component are all accommodated in the reaction chamber; the carrier stage is used for carrying a wafer; the heat source is used for heating the inside of the reaction chamber; the thermal compensation component is disposed opposite to the edge region of the wafer to at least heat the edge region of the wafer; The supply unit is connected to the reaction chamber and is used for supplying an etchant into the reaction chamber to remove a part of the thickness of the wafer.

2. The pre-cleaning device according to claim 1, wherein, The thermal compensation component includes a resistance wire and / or a heating lamp.

3. The pre-cleaning device according to claim 1 or 2, characterized in that, The reaction unit further includes a nozzle; the nozzle is disposed above the wafer, and the nozzle has a spraying surface and an inlet port, the spraying surface is disposed opposite to the surface of the wafer, and the inlet port is connected to the supply unit so that the etchant provided by the supply unit enters the nozzle through the inlet port and is sprayed onto the wafer surface through the spraying surface; Wherein, the thermal compensation component includes a resistance wire, the resistance wire is disposed in the nozzle and is disposed around the edge of the nozzle to at least heat the etchant sprayed out from the edge of the nozzle.

4. The pre-cleaning device according to claim 3, characterized in that, The distance range between the resistance wire and the edge of the nozzle is: 3 cm to 5 cm.

5. The pre-cleaning device according to claim 3, characterized in that, A heating coil is disposed in the nozzle; the heating coil is distributed inside the loop of the resistance wire and is spaced apart from the resistance wire.

6. The pre-cleaning device according to claim 5, characterized in that, The distance range between the heating coil and the edge of the nozzle is: 10 cm to 15 cm.

7. The pre-cleaning device according to claim 1 or 2, characterized in that The thermal compensation component includes a plurality of heating lamps, and the plurality of heating lamps are disposed above the wafer and are disposed opposite to the edge region of the wafer.

8. A semiconductor device, characterized in that, Including the pre-cleaning device according to any one of claims 1 to 7.

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