Shower unit, semiconductor device, and wafer processing method

Abstract

The present invention provides a shower unit, a semiconductor device, and a method for processing a wafer. In an annular region of the shower plate, a plurality of independent shower regions are formed, and the flow rate and concentration of reactants flowing in as required can be adjusted respectively. These shower regions are annularly distributed and can be arranged in an edge region of a central gas inlet. By adjusting the flow rate and concentration of reactants flowing into different shower regions respectively as required, the consistency of wafer surface process parameters is adjusted, and the purpose of enhancing the uniformity of the deposition thickness between the wafer edge region and the central region is achieved, and an annular shower head plate is provided.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor devices and manufacturing, and particularly to a shower unit, a semiconductor device, and a method for processing a wafer.

Background Art

[0002] Plasma enhancement technology is widely applied in the field of semiconductor manufacturing. It can increase the activation energy of reactants in the reaction process, simultaneously significantly reduce the reaction deposition temperature, and reduce the stress generated by the mismatch of the thermal expansion coefficient between the deposition layer and the base layer.

[0003] Remote Plasma System (RPS) Atomic Layer Deposition (ALD) is a type of ALD device. The plasma generated after the reaction gas is RF processed is supplied from the inlet to the inside of the chamber. This method has a small impact on the wafer surface and small plasma damage generated. However, since the remote plasma is relatively far from the wafer and the diffusion path is long, the distribution of excited state ion beams on the wafer surface is non-uniform. Usually, the density in the central region of the wafer is high, and the edge region is low, which causes the deposition thickness in the central and edge regions of the wafer to be non-uniform.

Summary of the Invention

[0004] Therefore, an object of the present invention is to provide a shower unit, a semiconductor device, and a method for processing a wafer that improve the uniformity of the deposition thickness between the wafer edge region and the central region. To achieve the above object, the present invention has the following technical solutions.

[0005] A shower unit applied to a semiconductor device and disposed in an edge region of a central gas inlet of the semiconductor device. The shower unit includes a first shower plate and a second shower plate disposed in a stacked manner, and the first shower plate and the second shower plate are annular plates disposed coaxially.

[0006] The first shower plate is provided with a first annular shower area and a shower introduction area arranged coaxially therewith.

[0007] The second shower plate is provided with a second annular shower region arranged coaxially therewith, the second annular shower region and the shower introduction region being arranged in correspondence, the shower introduction region being for introducing the reactants in the second annular shower region into the chamber, and the first annular shower region and the second annular shower region being independent of each other.

[0008] Optionally, the first annular shower region forms an inner ring shower region, and the second annular shower region, together with the shower introduction region, forms an outer ring shower region.

[0009] Optionally, the second annular shower region, together with the shower introduction region, forms an inner ring shower region, and the first annular shower region, together with the shower introduction region, forms an outer ring shower region.

[0010] Optionally, the first shower plate is further provided with a first gas inlet hole connected to the first annular shower area, and the second shower plate is further provided with a second gas inlet hole connected to the second annular shower area.

[0011] Optionally, the first annular shower region includes a first annular groove and a first shower hole penetrating the first annular groove; the second annular shower region includes a second annular groove and a second shower hole penetrating the second annular groove; the shower introduction region includes an annular through-hole region disposed on the first shower plate, the annular through-hole region having through holes, and the second shower hole penetrating at least partially through the through holes.

[0012] Optionally, the first and second shower holes are uniformly distributed, and the hole diameter range is 0.2 to 3 mm.

[0013] Optionally, the second shower plate is positioned below the lid plate of the chamber of the semiconductor device, and the first shower plate is positioned below the second shower plate.

[0014] A shower unit including an annular plate, wherein a first shower region and a second shower region are spaced apart and arranged coaxially on the annular plate, the first shower region including an inner groove ring and a first shower nozzle installed on the inner groove ring, and the second shower region including an outer groove ring and a second shower nozzle installed on the outer groove ring.

[0015] Optionally, a gas inlet cover plate is located above the annular plate, and the gas inlet cover plate is provided with a first gas inlet passage and a second gas inlet passage, the first gas inlet passage passing through the inner groove ring and the second gas inlet passage passing through the outer groove ring.

[0016] Optionally, the system further comprises a gas inlet lid plate located above the annular plate, the gas inlet lid plate having a first gas inlet passage connected to the inner groove ring, and the annular plate having a second gas inlet passage connected to the outer groove ring.

[0017] Optionally, the gas inlet lid plate is a chamber lid plate.

[0018] The remote plasma ALD apparatus includes a tubular RF generator and a reaction chamber, wherein a central gas inlet is located above the reaction chamber, the central gas inlet is located corresponding to the outlet of the tubular RF generator, and within the reaction chamber, a shower unit according to any one of the above items is located below the tubular RF generator.

[0019] Optionally, the tubular RF generator includes a gas pipe and a plurality of coil tubes arranged around the outer circumference of the gas pipe, each coil tube containing a spirally arranged coil, and the plurality of coil tubes having different diameters.

[0020] This is a wafer processing method characterized by placing the wafer in a reaction chamber of any one of the semiconductor devices described in the above-mentioned item and performing a process on the wafer.

[0021] The present invention provides a shower unit, semiconductor device, and wafer processing method, which, in its embodiments, allows for the formation of multiple independent shower regions in the annular region of the shower plate, enabling adjustment of the flow rate and concentration of reactants flowing into each region as needed, and these shower regions are annularly distributed and can be positioned in the edge region of the central gas inlet. By adjusting the flow rate and concentration of reactants flowing into different shower regions as needed, the invention provides an annular shower head plate that achieves the objective of adjusting the consistency of wafer surface process parameters and improving the uniformity of the deposition thickness between the wafer edge region and the central region. [Brief explanation of the drawing]

[0022] To more clearly illustrate embodiments of the present invention or technical solutions in the prior art, the drawings necessary for use in the description of embodiments or prior art are briefly described below. Clearly, the drawings in the following description are some embodiments of the present invention, and a general expert in the art can obtain other drawings based on these, provided they do not expend any creative labor. [Figure 1A] This shows a schematic diagram of the three-dimensional structure of a shower unit according to Embodiment 1 of the present invention. [Figure 1B] This shows a schematic cross-sectional view of a semiconductor device in which Embodiment 1 of the present invention is arranged. [Figure 2A] This shows a schematic diagram of the three-dimensional structure of a shower unit according to Embodiment 2 of the present invention. [Figure 2B]Shows a schematic cross-sectional structure of a semiconductor device in which Embodiment 2 of the present invention is arranged. [Figure 3A] Shows a schematic three-dimensional structure of a shower unit according to Embodiment 3 of the present invention. [Figure 3B] Shows a schematic three-dimensional structure of a chamber lid plate combined with Embodiment 3 of the present invention. [Figure 3C] Shows a schematic cross-section of FIG. 3B. [Figure 3D] Shows a schematic cross-sectional structure of a semiconductor device in which Embodiment 3 of the present invention is arranged.

Mode for Carrying Out the Invention

[0023] In order to make the above objects, features, and advantages of the present invention clearer and easier to understand, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0024] In the following description, many specific details have been described in order to fully understand the present invention. However, the present invention can also be implemented in other ways different from those described in this specification, and those skilled in the art can carry out similar popularization without departing from the content of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0025] As described in the technical background explanation, in a remote plasma ALD device, reactant gas is introduced from the central gas inlet, and the remote plasma is relatively far from the wafer, and the diffusion path is long. Therefore, the distribution of excited state ion beams on the wafer surface becomes non-uniform, causing non-uniform deposition thickness between the wafer center and the edge region.

[0026] Therefore, this patent provides a shower unit that can be positioned around the central gas inlet of a remote plasma ALD apparatus, forming multiple annular independent shower regions, thereby adjusting the flow rate and concentration of reactants flowing into different shower regions as needed, supplementing and adjusting the gas flow density in the edge region, and further improving the process consistency between the edge region and the central region. To better understand the present invention, different embodiments will be described below, and the following will be described using the assembly structure of two annular independent shower regions as an example.

[0027] In one embodiment, two independent shower regions can be formed on two shower plates, with one shower region and shower introduction region on one shower plate, and another shower region on the other shower plate, with the shower region and shower introduction region positioned in correspondence, and the reactant being flowed into the shower region and then into the chamber via the shower introduction region. In these embodiments, the realization of independent shower regions is more flexible. Embodiments 1 and 2

[0028] As shown in Figures 1A, 1B, and 2A, 2B, the shower unit includes a first shower plate 110 and a second shower plate 120 arranged in a stack, with the two shower plates positioned coaxially.

[0029] The first shower plate 110 is equipped with a first annular shower region 112 and a shower introduction region 114, respectively, while the second shower plate 120 is equipped with a second annular shower region 124, which is located in a position corresponding to the shower introduction region 114. The shower introduction region 114 corresponds to the second shower region 124 in terms of position, and this is to introduce the reactants in the second shower region 124 into the chamber.

[0030] In embodiments of the present invention, the annular shower regions 112 and 124 can introduce reactants and further have reactant volume spaces and reactant outflow shower holes, the volume spaces can be formed jointly with adjacent components during use, and the shower introduction region 114 is for further introducing reactants in the shower region 124 into the chamber. The first annular shower region 112 and the second annular shower region 124 are independent shower regions, the reactant volume spaces are independent of each other, and the reactant inflow paths are also independent.

[0031] In some applications, the first annular shower region 112 may include a first groove formed in the first shower plate 110 and a first shower nozzle formed in the first groove, the second annular shower region 124 may include a second groove formed in the second shower plate 120 and a second shower nozzle formed in the second groove, and the shower introduction region 114 may include an annular through-hole region, i.e., an annular region formed by through-holes, which are located on the first shower plate, and the through-holes in the annular through-hole region and the second through-holes provided in the second annular shower region 124 are at least partially interconnected, thereby enabling the reactants in the second shower region 124 to penetrate into the chamber.

[0032] The first shower holes, the second shower holes, and the through holes are regularly distributed through holes. In specific embodiments, these through holes can adopt the same or different layout methods, and the diameters of the through holes can be the same or different, with the diameters of these through holes preferably being selected within the range of 0.2 to 3 mm.

[0033] As shown in Figures 1A and 1B, in Embodiment 1, the first shower plate 110 is located below the second shower plate 120, the first annular shower region 112 forms an inner ring shower region, and the second annular shower region 124 forms an outer ring shower region.

[0034] The first shower plate 110 is further provided with a first gas inlet hole 116 that penetrates the inner ring shower region 112, and reactants are introduced into the inner ring shower region through the gas inlet hole 116 located in the first shower plate 110. The second shower plate 120 is provided with a second gas inlet hole 126 that penetrates the outer ring shower region 124, and reactants are introduced into the outer ring shower region through the gas inlet hole 126 located in the second shower plate 120.

[0035] As shown in Figures 2A and 2B, in Embodiment 2, the first shower plate 210 is located below the second shower plate 220, and the first annular shower area 212 is located outside ring To form a shower area, the second annular shower area 224 is inside ring This is to form a shower area. The first shower plate 210 has an outer ring A first gas inlet hole 216 is also provided, which penetrates the shower area 212, and reactants are removed through the gas inlet hole 216 located in the first shower plate 210. ring It is introduced into the shower area, and the second shower plate 220 has ring A second gas inlet hole 226 is provided that penetrates the shower area 224, and reactants are brought in through the gas inlet hole 226 located in the second shower plate 220. ring It will be installed in the shower area. Similar to Example 1, in this embodiment, the reactants are introduced into the shower area by arranging gas inlet holes in the shower plate, which has a simple structure and is easy to integrate. In other embodiments, this can be achieved in other ways, for example, by separately arranging a lid plate with ventilation passages, which is positioned above the shower plate, and the reactants can be introduced from above the shower area through the ventilation passages in the lid plate.

[0036] As shown in Figures 2A and 2B, in Embodiment 2, the first shower plate 210 is located below the second shower plate 220, the first annular shower region 212 forms an outer annular shower region, and the second annular shower region 224 forms an inner annular shower region. The first shower plate 210 also has a first gas inlet hole 216 that penetrates the outer annular shower region 212, and reactants are introduced into the outer annular shower region through the gas inlet hole 216 in the first shower plate 210. The second shower plate 220 has a second gas inlet hole 226 that penetrates the inner annular shower region 224, and reactants are introduced into the inner annular shower region through the gas inlet hole 226 in the second shower plate 220. Similar to Example 1, in this embodiment, the reactants are introduced into the shower area by arranging gas inlet holes in the shower plate, which has a simple structure and is easy to integrate. In other embodiments, this can be achieved in other ways, for example, by separately arranging a lid plate with ventilation passages, which is positioned above the shower plate, and the reactants can be introduced from above the shower area through the ventilation passages in the lid plate.

[0037] In the specific application of the above embodiment, the second shower plate 120 can be located below the chamber lid plate 18, and the second annular shower region 124, together with the adjacent chamber lid plate 18, forms a volume space for the reactants. The first shower plate 110 is located below the second shower plate 120, and the first annular shower region 112, together with the adjacent second shower plate 120, forms a volume space for the reactants.

[0038] In order to facilitate understanding of the specific configuration of the embodiment of the present invention, the cross-sectional views provided in Figures 1B and 2B both show cross-sectional views created along the positions of the first gas inlet and the second gas inlet. However, these do not represent the actual relative positional relationship between the two. In actual applications, the first gas inlet and the second gas inlet can be positioned at appropriate locations on the first shower plate and the second shower plate, respectively.

[0039] Embodiment 3 In other embodiments, different annular shower regions can be arranged on a single shower plate, resulting in a simpler structure. As shown in Figures 3A to 3D, these embodiments include an annular plate 300, the annular plate 300 having a first shower region 302 and a second shower region 304 arranged coaxially at intervals, the first shower region 302 including an inner groove ring and a first shower nozzle positioned in the inner groove ring, and the second shower region 304 including an outer groove ring and a second shower nozzle positioned in the outer groove ring.

[0040] The reactants are introduced into the first shower area 302 and the second shower area 304, respectively, through independent gas inlet passages. Another gas inlet lid plate can accommodate some or all of the gas inlet passages, and the gas inlet piping in the gas inlet lid plate supplies the reactants to the shower areas from above.

[0041] In some specific embodiments, as shown in Figures 3A to 3D, a gas inlet lid plate 18 is included, which is positioned above the annular plate 300, and which has a first gas inlet passage 312 and a second gas inlet 314, respectively, the first gas inlet passage 312 passing through the inner groove ring and the second gas inlet passage 314 passing through the outer groove ring.

[0042] In another specific embodiment (not shown), a gas inlet lid plate is further located above the annular plate, the gas inlet lid plate having a first gas inlet passage that communicates with the inner groove ring, and the annular plate having a second gas inlet passage that extends to the outer groove ring.

[0043] The gas inlet lid plate 18 may be an independent lid plate structure or may be integrated with other structures. In a preferred embodiment, the gas inlet lid plate 18 may be a chamber lid plate.

[0044] The shower unit of the embodiment of the present invention has been described in detail above. The present invention also provides the above remote plasma ALD apparatus, which includes a tubular RF generator and a reaction chamber 20, as shown in reference Figures 1B, 2B, and 3D, wherein a central gas inlet is located above the reaction chamber 20, and a shower unit of any of the above structures is located below the tubular RF generator within the reaction chamber 20, with the annular shower region of the shower unit located around the gas outlet of the tubular RF generator. The tubular RF generator converts the incoming process gas into plasma reactants using RF. A susceptor 22 is installed inside the chamber, with wafers awaiting processing placed above the susceptor 22. The gas outlet of the tubular RF generator is located above the central region of the wafer 24. Because the remote plasma is relatively far from the wafer, the diffusion path is long, resulting in an uneven distribution of excited ion beams on the wafer surface. The density is high in the central region of the wafer and low in the edge region. An independent edge shower region is installed in the shower unit, located around the main gas inlet hole. By arranging the shower unit, the flow rate and concentration of the incoming reactants can be adjusted as needed, further optimizing the consistency of process parameters on the wafer surface. This achieves the objective of improving the uniformity of the deposition thickness in the wafer edge and central regions.

[0045] In embodiments of the present invention, the tubular RF generator includes a gas passage 15 and a plurality of coil tubes 14, 16, each coil tube containing coils arranged in a spiral, with one or more coils, and the plurality of coil tubes 14, 16 having different diameters. By setting different powers to different coils, after the process gas flows in from the gas inlet hole, the smaller diameter coil tubes first achieve plasma ignition and diffuse downwards as the gas flows, while the larger diameter coil tubes initiate plasma excitation and further improve the uniformity of the edge plasma distribution.

[0046] Furthermore, the present invention provides a wafer processing method in which a wafer is set in the remote plasma ALD device described above, and then a process is performed on the wafer. The above describes only preferred embodiments of the present invention, and while the present invention is disclosed above by preferred embodiments, it is not intended to limit the present invention. Those skilled in the art can, without departing from the scope of the art, make many possible changes and modifications to the scope of the art of the present invention using the methods and art content disclosed above, or modify them into equivalent embodiments of equivalent changes. Accordingly, any simple modifications, equivalent changes and modifications substantially made to the above embodiments based on the art substance of the present invention are within the scope of the art of the present invention, as long as they do not depart from the scope of the art of the present invention.

Claims

1. A shower unit applied to a semiconductor device, which is disposed in the edge region of the central gas inlet of the semiconductor device, The shower unit includes a first shower plate and a second shower plate arranged in a stack, and the first shower plate and the second shower plate are annular plates arranged coaxially. Here, the first shower plate comprises a first annular shower area and a shower introduction area, A shower unit comprising a second shower plate having a second annular shower region, wherein the second annular shower region and the shower introduction region are arranged in correspondence, the shower introduction region is for introducing the reactants in the second annular shower region into a chamber, and the first annular shower region and the second annular shower region are independent shower regions of each other.

2. The shower unit according to claim 1, characterized in that the first annular shower region forms an inner ring shower region, and the second annular shower region, together with the shower introduction region, forms an outer ring shower region.

3. The shower unit according to claim 1, characterized in that the second annular shower region, together with the shower introduction region, forms an inner ring shower region, and the first annular shower region forms an outer ring shower region.

4. The shower unit according to claim 1, characterized in that the first shower plate is further provided with a first gas inlet hole connected to the first annular shower area, and the second shower plate is further provided with a second gas inlet hole connected to the second annular shower area.

5. The shower unit according to any one of claims 1 to 4, wherein the first annular shower region includes a first annular groove and a first shower hole penetrating the first annular groove, the second annular shower region includes a second annular groove and a second shower hole penetrating the second annular groove, the shower introduction region includes an annular through-hole region disposed on the first shower plate, the annular through-hole region has through holes, and the second shower hole penetrates at least a portion of the through holes.

6. The shower unit according to claim 5, characterized in that the first shower holes and the second shower holes are uniformly distributed and the hole diameter range is 0.2 to 3 mm.

7. The shower unit according to claim 5, wherein the second shower plate is positioned below the lid plate of the chamber of the semiconductor device, and the first shower plate is positioned below the second shower plate.

8. A semiconductor device comprising a remote plasma ALD apparatus, a tubular RF generator and a reaction chamber, wherein a central gas inlet is located above the reaction chamber, the central gas inlet is located corresponding to the outlet of the tubular RF generator, and a shower unit according to any one of claims 1 to 4 is provided inside the reaction chamber below the tubular RF generator.

9. The semiconductor device according to claim 8, wherein the tubular RF generator includes a gas pipe and a plurality of coil tubes provided on the outer circumference of the gas pipe, each coil tube includes coils arranged in a spiral shape, and the plurality of coil tubes have different diameters.

10. A wafer processing method characterized by placing a wafer in the reaction chamber of a semiconductor device described in Claim 8 and performing a process on the wafer.

Images