Process chamber for back deposition and back deposition equipment for semiconductor device

Abstract

The invention provides a process chamber for back deposition and back deposition equipment for a semiconductor device. The process chamber for back surface deposition comprises a heating plate which is located at the upper part of the process chamber and is used for heating the front surface of a wafer, and a plurality of air passing through holes are formed in the heating plate; the spraying plate is positioned at the lower part of the process chamber and is used for providing process gas for the back surface of the wafer so as to be matched with the heating plate to perform back surface film deposition on the wafer; and the first gas inlet is located in the heating plate and used for providing cleaning gas to the position above the heating plate, and the cleaning gas uniformly flows to a central area between the heating plate and the spraying plate through the gas passing through holes in the heating plate so as to clean the central area.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor manufacturing, and in particular to a backside deposition process chamber and a backside deposition device for a semiconductor device. Background Art

[0002] In the semiconductor manufacturing process, according to the semiconductor process requirements and device applications, a layer of thin film needs to be deposited on the back of the wafer through a back deposition device. This process requires high precision and cleanliness to maintain the stability of the semiconductor manufacturing process and the quality of the product. Traditional back deposition equipment usually uses dry cleaning, and its cleaning gas has only one inflow channel, and the back deposition equipment is cleaned by edge inflow or middle inflow. Therefore, this method inevitably has the problem of uneven cleaning speed in the edge area and middle area of ​​the flow channel, and large differences in the degree of fluorination at different positions in the chamber, which ultimately leads to process drift and the generation of thin film particles, which has an adverse effect on product yield.

[0003] The prior art discloses a technical solution as shown in CN 115810564 A, which is a semiconductor processing chamber for front deposition and a cleaning method thereof. In the technical solution, a shower head with a ventilation function is arranged above the heating plate, and a gas extraction port is arranged below the process chamber. However, if the device is configured in a back deposition device, the shower head is arranged below the heating plate, resulting in that when the gas is extracted through the gas extraction port below the process chamber, the lower shower head sprays cleaning gas upward to clean it, resulting in the problem that the upper area cannot be cleaned.

[0004] In order to overcome the above-mentioned defects of the prior art, there is an urgent need in the art for a cleaning technology for providing uniform cleaning gas to the process chamber to improve the yield of the product. Summary of the invention

[0005] A brief summary of one or more aspects is given below to provide a basic understanding of these aspects. This summary is not an exhaustive overview of all conceived aspects, and is neither intended to identify the key or decisive elements of all aspects nor to define the scope of any or all aspects. Its only purpose is to give some concepts of one or more aspects in a simplified form as a prelude to a more detailed description that will be given later.

[0006] In order to overcome the above-mentioned defects in the prior art, the present invention provides a backside deposition process chamber and a backside deposition device for a semiconductor device, which are used to provide uniform cleaning gas to the process chamber to improve the yield of the product.

[0007] Specifically, the back-side deposition process chamber provided according to the first aspect of the present invention includes: a heating plate, located at the upper part of the process chamber, for heating the front side of the wafer, wherein a plurality of gas holes are provided on the heating plate; a spray plate, located at the lower part of the process chamber, for providing process gas to the back side of the wafer, so as to cooperate with the heating plate to perform back-side thin film deposition on the wafer; and a first air inlet, located above the heating plate, for providing a cleaning gas to the top of the heating plate, wherein the cleaning gas flows evenly to the central area between the heating plate and the spray plate through the plurality of gas holes on the heating plate, so as to clean the central area.

[0008] Furthermore, in some embodiments of the present invention, the process chamber also includes: a gas uniforming sleeve, which surrounds the top of the heating plate and maintains a gas uniforming ring between the heating plate, wherein the first gas inlet is connected to the gas uniforming ring to provide the cleaning gas to the top of the heating plate.

[0009] Furthermore, in some embodiments of the present invention, the air aperture of the air uniforming annular channel decreases with the distance from the air uniforming annular channel to the first air inlet, and / or the air aperture of the air through hole increases with the distance from the air uniforming annular channel to the first air inlet.

[0010] Furthermore, in some embodiments of the present invention, the process chamber further comprises: a second gas inlet, which is located above the gas uniformizing bushing and connected to the outer area of ​​the gas uniformizing annulus to provide the cleaning gas to the top of the gas uniformizing bushing.

[0011] Furthermore, in some embodiments of the present invention, the process chamber also includes: a wafer support mechanism, located between the heating plate and the spray plate, for supporting the wafer and exposing its back side to perform the back side thin film deposition thereon, wherein the cleaning gas flows evenly to a first middle area between the heating plate and the wafer support mechanism through the multiple gas holes on the heating plate, and the cleaning gas also flows through the outer area of ​​the uniform gas ring channel to a second middle area between the wafer support mechanism and the spray plate to evenly clean the first middle area and the second middle area.

[0012] Furthermore, in some embodiments of the present invention, the process chamber further comprises: a cleaning gas source connected to the first gas inlet and / or the second gas inlet to provide the cleaning gas thereto.

[0013] Furthermore, in some embodiments of the present invention, the process chamber also includes: a remote plasma system, located between the cleaning gas source and the first gas inlet and / or the second gas inlet, for exciting the cleaning gas provided by the cleaning gas source and transmitting the plasma generated by the excitation to the first gas inlet and / or the second gas inlet to clean the process chamber.

[0014] Furthermore, in some embodiments of the present invention, the process chamber further comprises: at least one exhaust port, located below the shower plate, to extract waste gas in the process chamber.

[0015] Furthermore, in some embodiments of the present invention, the process chamber comprises a plurality of exhaust ports, wherein the exhaust ports are symmetrically arranged around a longitudinal center axis of the process chamber to uniformly extract exhaust gas from the process chamber.

[0016] Furthermore, in some embodiments of the present invention, the shower plate of the process chamber is also configured with a heating element for heating the back side of the wafer and / or heating the process gas to promote thin film deposition on the back side of the wafer.

[0017] In addition, the back side deposition equipment of the semiconductor device provided according to the second aspect of the present invention comprises at least one process chamber as described in any one of the first aspect of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above features and advantages of the present invention can be better understood after reading the detailed description of the embodiments of the present disclosure in conjunction with the following drawings. In the drawings, the components are not necessarily drawn to scale, and components with similar related properties or features may have the same or similar reference numerals.

[0019] Figure 1 A schematic structural diagram of a backside deposition process chamber provided according to some embodiments of the present invention is shown.

[0020] Figure 2 A schematic diagram of a remote plasma structure of multiple process chambers provided according to some embodiments of the present invention is shown.

[0021] Reference numerals:

[0022] 10 Heating plate

[0023] 20 Spray plate

[0024] 30 Air-distributing bushing

[0025] 41 First air inlet

[0026] 42 Second air inlet

[0027] 50 Wafer support mechanism

[0028] 60 Remote Plasma System

[0029] 70 Air extraction port DETAILED DESCRIPTION

[0030] The following specific embodiments illustrate the implementation of the present invention, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Although the description of the present invention will be introduced in conjunction with the preferred embodiment, this does not mean that the features of this invention are limited to this implementation. On the contrary, the purpose of introducing the invention in conjunction with the implementation is to cover other options or modifications that may be extended based on the claims of the present invention. In order to provide a deep understanding of the present invention, the following description will include many specific details. The present invention can also be implemented without using these details. In addition, in order to avoid confusion or blurring the focus of the present invention, some specific details will be omitted in the description.

[0031] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] In addition, the terms "upper", "lower", "left", "right", "top", "bottom", "horizontal" and "vertical" used in the following description should be understood as the directions shown in the paragraph and the related drawings. Such relative terms are only used for the convenience of description and do not mean that the device described therein must be manufactured or operated in a specific direction, and therefore should not be understood as limiting the present invention.

[0033] It is understood that although the terms "first", "second", "third", etc. may be used herein to describe various components, regions, layers and / or parts, these components, regions, layers and / or parts should not be limited by these terms, and these terms are only used to distinguish different components, regions, layers and / or parts. Therefore, the first component, region, layer and / or part discussed below may be referred to as a second component, region, layer and / or part without departing from some embodiments of the present invention.

[0034] As mentioned above, in the semiconductor manufacturing process, according to the semiconductor process requirements and the application of the device, a layer of thin film needs to be deposited on the back of the wafer through a back deposition device. This process requires high precision and cleanliness to maintain the stability of the semiconductor manufacturing process and the quality of the product. Traditional back deposition equipment usually uses dry cleaning, and its cleaning gas has only one inflow channel, and the back deposition equipment is cleaned by edge inflow or middle inflow. Therefore, this method inevitably has the problem of uneven cleaning speed in the edge area and middle area of ​​the flow channel, and large differences in the degree of fluorination at different positions in the chamber, which ultimately leads to process drift and the generation of thin film particles, which has an adverse effect on product yield.

[0035] In order to overcome the above-mentioned defects in the prior art, the present invention provides a backside deposition process chamber and a backside deposition device for a semiconductor device, which are used to provide uniform cleaning gas to the process chamber to improve the yield of the product.

[0036] In some non-limiting embodiments, the backside deposition process chamber provided by the first aspect of the present invention may be implemented based on the backside deposition equipment of the semiconductor device provided by the second aspect of the present invention.

[0037] Specifically, the backside deposition process mainly refers to depositing one or more layers of material on the back side of the semiconductor wafer, which is used to reduce light transmission, dissipate heat or perform electrical isolation, etc., to improve device performance. Specifically, for some semiconductor devices, such as image sensors, reducing backside light transmission can reduce noise and improve image quality. The specific material deposited on the back side can act as a heat dissipation layer to help conduct the heat generated by the chip more efficiently. In some designs, the backside deposition layer can act as an electrical isolation layer to prevent interference between the back and front circuits.

[0038] Furthermore, the backside deposition process can also improve processing flexibility, reduce frontside process steps, and improve production efficiency. Specifically, the backside deposition process can provide more flexibility for frontside processing because it is not limited by the frontside circuit layout, which allows for more complex or different material deposition on the backside without affecting the frontside circuit design. In addition, the method can be deposited on the backside after the wafer completes the frontside process, thereby achieving parallel processing of the front and backside processes and improving production efficiency. And by depositing on the backside, the complexity and steps of the frontside process can be reduced, the production process can be simplified, and costs can be reduced.

[0039] First, please refer to Figure 1 , Figure 1 A schematic structural diagram of a backside deposition process chamber provided according to some embodiments of the present invention is shown.

[0040] like Figure 1As shown, the backside deposition process chamber includes a heating plate 10 , a shower plate 20 , a first gas inlet 41 , a gas uniforming bushing 30 , a second gas inlet 42 and a gas extraction port 70 .

[0041] The heating plate 10 is located at the upper part of the process chamber and is used to heat the front side of the wafer. The heating plate 10 is provided with a plurality of gas through holes.

[0042] The shower plate 20 is located at the bottom of the process chamber and is used to provide process gas to the back side of the wafer to cooperate with the heating plate 10 to perform back side film deposition on the wafer. In some embodiments, the shower plate 20 is also configured with a heating element to heat the back side of the wafer and / or heat the process gas to promote back side film deposition on the wafer.

[0043] The first gas inlet 41 is located above the heating plate 10 and is used to provide a cleaning gas above the heating plate 10. Here, the cleaning gas is mainly a fluorine-containing gas, such as a mixed gas of nitrogen trifluoride and argon. The cleaning gas flows evenly to the central area between the heating plate 10 and the shower plate 20 through a plurality of gas through holes on the heating plate 10 to clean the central area.

[0044] The uniform gas sleeve 30 surrounds the top of the heating plate 10 and maintains a uniform gas annulus between the heating plate 10. Here, the first gas inlet 41 is connected to the uniform gas annulus to provide clean gas to the top of the heating plate 10. The second gas inlet 42 is located above the uniform gas sleeve 30 and is connected to the outer area of ​​the uniform gas annulus to provide clean gas to the top of the uniform gas sleeve 30, thereby cleaning the upper area of ​​the heating plate 10.

[0045] In some embodiments, the cleaning gas source is connected to the first gas inlet 41 and / or the second gas inlet 42 to provide cleaning gas thereto. Here, the cleaning gas flow rates of the first gas inlet 41 and the second gas inlet 42 can be adjusted independently to improve cleaning uniformity.

[0046] In some embodiments, the vent diameter of the gas uniformity annular channel decreases with the distance from the first gas inlet 41 , thereby improving the uniformity of the gas pressure of the cleaning gas at different positions and improving the gas uniformity.

[0047] In some embodiments, the gas aperture of the gas through hole increases with the distance from the gas through hole to the first gas inlet 41 , thereby improving the uniformity of the flow resistance of the cleaning gas at different positions and improving the gas uniformity.

[0048] The at least one exhaust port 70 is located below the shower plate 20 to extract the waste gas in the process chamber. Here, the waste gas in the process chamber, including but not limited to excess process gas, process tail gas, and clean tail gas, is more likely to flow into the front area of ​​the wafer, causing unnecessary film growth on the front of the wafer. Therefore, the exhaust hole can cooperate with the shower plate 20 located at the bottom of the process chamber to timely extract excess process gas and process tail gas to avoid film growth on the front of the wafer.

[0049] Furthermore, the gas extraction port 70 can cooperate with a cleaning method in which a cleaning gas is input from the upper part of the process chamber via the heating plate 10, so that the cleaning gas can fully flow through the entire process chamber to improve the cleaning effect and cleaning uniformity.

[0050] In some embodiments, the process chamber may include a plurality of gas extraction ports 70. Further, the gas extraction ports 70 are symmetrically arranged around the longitudinal central axis of the process chamber to uniformly extract the exhaust gas in the process chamber.

[0051] In addition, the process chamber may also include a wafer support mechanism 50 (e.g., an edge ring), which is located between the heating plate 10 and the shower plate 20, and is used to support the wafer and expose its back side for back side thin film deposition, wherein the cleaning gas flows evenly to the first middle area (i.e., the secondary reaction area on the front side of the wafer) between the heating plate 10 and the wafer support mechanism 50 through a plurality of gas through holes on the heating plate 10, and the cleaning gas also flows to the second middle area (i.e., the main reaction area on the back side of the wafer) between the wafer support mechanism 50 and the shower plate 20 through the outer area of ​​the uniform gas ring channel, so as to evenly clean the first middle area and the second middle area.

[0052] Please refer to Figure 2 , Figure 2 A schematic diagram of a remote plasma structure of multiple process chambers provided according to some embodiments of the present invention is shown.

[0053] like Figure 2 As shown, the backside deposition equipment of the semiconductor device includes at least one process chamber, including but not limited to 1, 2 and 4.

[0054] In addition, the process chamber may further include a remote plasma system 60. The remote plasma system 60 is located between the cleaning gas source and the first gas inlet 41 and / or the second gas inlet 42, and is used to excite the cleaning gas provided by the cleaning gas source and transmit the plasma generated by the excitation to the first gas inlet 41 and / or the second gas inlet 42 to clean the process chamber, thereby further improving the cleaning effect.

[0055] The working principle of the above-mentioned backside deposition process chamber and the backside deposition equipment of the semiconductor device will be described below in combination with some embodiments of the backside deposition process chamber cleaning method.

[0056] First, the process chamber for backside deposition starts a clean gas source to output clean gas, wherein the clean gas source can also be transmitted to the process chamber via plasma generated by a remote plasma system.

[0057] Afterwards, the cleaning gas flows evenly through the multiple gas holes on the heating plate 10 to the secondary reaction area on the front side of the wafer between the heating plate 10 and the wafer support mechanism 50 to evenly clean the area. The cleaning gas also flows through the outer area of ​​the uniform gas ring to the main reaction area on the back side of the wafer between the wafer support mechanism 50 and the shower plate 20 to evenly clean the area.

[0058] Those skilled in the art can understand that the embodiments of the back-side deposition process chamber cleaning method are only some non-limiting implementation methods provided by the present invention, which are intended to clearly demonstrate the main concept of the present invention and provide some specific solutions that are convenient for the public to implement, rather than to limit all functions or all working modes of the back-side deposition process chamber and the back-side deposition equipment of the semiconductor device. Similarly, the back-side deposition process chamber and the back-side deposition equipment of the semiconductor device are only some non-limiting implementation methods provided by the present invention, and do not constitute a limitation on the execution subject or execution order of each step in the back-side deposition process chamber cleaning method.

[0059] In summary, the cleaning technology provided by the present invention can be used to provide uniform cleaning gas to the process chamber to improve the yield of the product.

[0060] Although the above methods are illustrated and described as a series of actions for simplicity of explanation, it should be understood and appreciated that these methods are not limited by the order of the actions, because according to one or more embodiments, some actions may occur in a different order and / or concurrently with other actions from those illustrated and described herein or not illustrated and described herein but understandable to those skilled in the art.

[0061] Those skilled in the art will further appreciate that the various illustrative logic blocks, modules, circuits, and algorithm steps described in conjunction with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or a combination of the two. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps are generally described above in terms of their functionality. Whether such functionality is implemented as hardware or software depends on the specific application and the design constraints imposed on the overall system. The technician may implement the described functionality in different ways for each specific application, but such implementation decisions should not be interpreted as resulting in a departure from the scope of the present invention.

[0062] Although the controller of the above-mentioned embodiment can be implemented by a combination of software and hardware. However, it is understood that the controller can also be implemented in software and hardware. For hardware implementation, the controller can be implemented in one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, other electronic devices for performing the above functions, or a selection combination of the above devices. For software implementation, the controller can be implemented by independent software modules such as procedures and functions running on a general-purpose chip, each of which performs one or more functions and operations described herein.

[0063] The various illustrative logic modules and circuits described in conjunction with the embodiments disclosed herein may be implemented or executed with a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in cooperation with a DSP core, or any other such configuration.

[0064] The previous description of the disclosure is provided to enable any person skilled in the art to make or use the disclosure. Various modifications to the disclosure will be apparent to those skilled in the art, and the general principles defined herein may be applied to other variations without departing from the spirit or scope of the disclosure. Thus, the disclosure is not intended to be limited to the examples and designs described herein, but should be granted the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A backside deposition process chamber, characterized in that: include: A heating plate, located at the upper part of the process chamber, for heating the front side of the wafer, wherein a plurality of gas through holes are provided on the heating plate; a shower plate, located at the lower part of the process chamber, for providing process gas to the back side of the wafer, so as to cooperate with the heating plate to perform back side thin film deposition on the wafer; and A first air inlet is located above the heating plate and is used to provide a cleaning gas to the top of the heating plate, wherein the cleaning gas flows evenly to the central area between the heating plate and the spray plate through the multiple gas through holes on the heating plate to clean the central area.

2. The process chamber according to claim 1, characterized in that: Also includes: The gas-uniform bushing surrounds the top of the heating plate and maintains a gas-uniform annular channel between the heating plate and the first air inlet, wherein the first air inlet is connected to the gas-uniform annular channel to provide the cleaning gas to the top of the heating plate.

3. The process chamber according to claim 2, characterized in that: The vent diameter of the air-uniform annular channel decreases with the distance from the annular channel to the first air inlet, and / or The air passage diameter of the air passage hole increases with the distance from the air passage hole to the first air inlet.

4. The process chamber according to claim 2, characterized in that: Also includes: The second air inlet is located on the gas-uniform bushing and is connected to the outer area of ​​the gas-uniform annular channel to provide the clean gas to the upper part of the gas-uniform bushing.

5. The process chamber according to claim 4, characterized in that: Also includes: A wafer support mechanism is located between the heating plate and the spray plate, and is used to support the wafer and expose its back side for back side thin film deposition, wherein the cleaning gas flows evenly to a first middle area between the heating plate and the wafer support mechanism through the multiple gas through holes on the heating plate, and the cleaning gas also flows to a second middle area between the wafer support mechanism and the spray plate through an outer area of ​​the uniform gas ring channel, so as to evenly clean the first middle area and the second middle area.

6. The process chamber according to claim 4, characterized in that: Also includes: A cleaning gas source is connected to the first gas inlet and / or the second gas inlet to provide the cleaning gas thereto.

7. The process chamber according to claim 6, characterized in that: Also includes: A remote plasma system is located between the cleaning gas source and the first gas inlet and / or the second gas inlet, and is used to excite the cleaning gas provided by the cleaning gas source and transmit the plasma generated by the excitation to the first gas inlet and / or the second gas inlet to clean the process chamber.

8. The process chamber according to claim 1, wherein: Also includes: At least one exhaust port is located below the shower plate to extract waste gas in the process chamber.

9. The process chamber according to claim 8, characterized in that: The process chamber includes a plurality of the exhaust ports, wherein the exhaust ports are symmetrically arranged around a longitudinal central axis of the process chamber to uniformly extract waste gas in the process chamber.

10. The process chamber according to claim 1, wherein: The shower plate is also configured with a heating element for heating the back side of the wafer and / or heating the process gas to promote thin film deposition on the back side of the wafer.

11. A backside deposition device for a semiconductor device, characterized in that: The process chamber comprises at least one process chamber according to any one of claims 1 to 10.

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