Semiconductor device and thin film deposition device and method thereof

Abstract

The present invention provides a thin film deposition device for a semiconductor device, a semiconductor device, a thin film deposition method for a semiconductor device, and a computer-readable storage medium. The thin film deposition device for a semiconductor device includes a reaction chamber, a radio frequency generator, an adjustable capacitor, and a controller, wherein the controller is configured to: determine a target energy density when performing thin film deposition on the semiconductor device; adjust the capacitance value of the adjustable capacitor according to the target energy density and the radio frequency frequency of the radio frequency generator so that the deposition power, radio frequency time, and deposition pressure in the reaction chamber match the target energy density; and perform thin film deposition on the semiconductor device based on the process conditions of the target energy density.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing technology, and in particular to a thin film deposition device for a semiconductor device, a semiconductor device, a thin film deposition method for a semiconductor device, and a corresponding computer-readable storage medium. Background Art

[0002] In the semiconductor field, thin film deposition is crucial for the processing of semiconductor devices. The current prior art in this field uses a high-frequency plasma generator (>60 MHz plasma generator) to control the conformality of the thin film wet etch rate (WER), and the matching process pressure range is limited to 4-7 Torr, which has process limitations, and the method is expensive, increasing the manufacturing cost.

[0003] In order to overcome the above-mentioned defects of the prior art, the art is in urgent need of a thin film deposition device for semiconductor devices, which can be used to achieve wide-range control of various thin film deposition process parameters (such as pressure / energy), improve the wet etching conformality of the thin film and increase the step coverage, and reduce the processing cost of semiconductor devices. Summary of the invention

[0004] 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.

[0005] In order to overcome the above-mentioned defects of the prior art, the present invention provides a thin film deposition device for semiconductor devices, which can realize a wide range of controllable process parameters (such as pressure / energy), improve the wet etching conformality and step coverage of the thin film, and reduce the processing cost of semiconductor devices.

[0006] Specifically, the thin film deposition apparatus for the semiconductor device provided according to the first aspect of the present invention comprises a reaction chamber, a radio frequency generator, an adjustable capacitor and a controller, wherein the controller is configured to: determine a target energy density for thin film deposition on the semiconductor device; adjust the capacitance value of the adjustable capacitor according to the target energy density and the radio frequency frequency of the radio frequency generator so that the deposition power, the radio frequency time and the deposition pressure in the reaction chamber match the target energy density; and perform thin film deposition on the semiconductor device based on the process conditions of the target energy density.

[0007] Furthermore, in some embodiments of the present invention, the step of determining the target energy density of thin film deposition on the semiconductor device includes: determining the target energy density of thin film deposition on the semiconductor device based on top conformality and / or sidewall conformality and / or bottom conformality required by the semiconductor device.

[0008] Furthermore, in some embodiments of the present invention, the step of determining the target energy density of thin film deposition on the semiconductor device based on the sidewall conformality and / or bottom conformality required by the semiconductor device includes: in response to the sidewall conformality and bottom conformality required by the semiconductor device being greater than a preset threshold, determining the target energy density to be between 48 and 80 kW·s·Torr.

[0009] Furthermore, in some embodiments of the present invention, the step of adjusting the capacitance value of the adjustable capacitor according to the target energy density, the RF frequency of the RF generator and the preset RF time includes: adjusting the capacitance value of the adjustable capacitor according to the target energy density, the RF frequency of the RF generator below 60 MHz and the preset RF time to expand the process window of the deposition power and the deposition pressure.

[0010] Furthermore, in some embodiments of the present invention, the RF frequency of the RF generator is 27 MHz, the process window of the deposition power is 600-2500 W, and the process window of the deposition pressure is 6-20 Torr.

[0011] Furthermore, in some embodiments of the present invention, the thin film deposition device also includes an AC filter for adjusting the 27 MHz radio frequency emitted by the RF generator to 13.5 MHz, and the controller is further configured to adjust the frequency of the radio frequency via the AC filter according to the target energy density.

[0012] Furthermore, in some embodiments of the present invention, after thin film deposition is performed on the semiconductor device, the thin film deposition device is also configured to: perform wet etching on the semiconductor device on which the thin film is deposited to obtain a thin film with the required top conformality and / or sidewall conformality and / or bottom conformality.

[0013] In addition, the thin film deposition method for semiconductor devices provided according to the second aspect of the present invention includes the following steps: determining a target energy density for thin film deposition on the semiconductor device; adjusting the capacitance value of an adjustable capacitor according to the target energy density and the RF frequency of an RF generator so that the deposition power, RF time and deposition pressure in the reaction chamber match the target energy density; and thin film deposition on the semiconductor device based on the process conditions of the target energy density.

[0014] In addition, the computer-readable storage medium provided in the third aspect of the present invention stores computer instructions, which, when executed by a processor, implement the thin film deposition method for a semiconductor device provided in the second aspect of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] 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.

[0016] Figure 1 A schematic structural diagram of a thin film deposition apparatus for a semiconductor device provided according to some embodiments of the present invention is shown.

[0017] Figure 2 A schematic diagram of film formation using a four-step cycle method according to some embodiments of the present invention is shown.

[0018] Figure 3 A schematic flow chart of a thin film deposition method for a semiconductor device provided according to some embodiments of the present invention is shown.

[0019] Figure 4 A schematic diagram of process control logic provided according to some embodiments of the present invention is shown.

[0020] Figure 5 Schematic diagram of top / sidewall / bottom film deposition at different energy densities provided according to some embodiments of the present invention is shown.

[0021] Fig. 6A A schematic diagram of a silicon nitride film deposited at an energy density of 48000 W·s·Torr after wet etching at different powers, RF times and pressures provided in some embodiments of the present invention is shown.

[0022] Figure 6B A schematic diagram of a silicon nitride film deposited at an energy density of 60000 W·s·Torr after wet etching at different powers, RF times and pressures provided in some embodiments of the present invention is shown.

[0023] Figure 6C A schematic diagram of a silicon nitride film deposited at an energy density of 80,000 W·s·Torr after wet etching at different powers, RF times and pressures provided in some embodiments of the present invention is shown.

[0024] Fig. 7AA schematic diagram of a silicon nitride film deposited at an energy density of 16000 W·s·Torr after wet etching at different powers, RF times and pressures according to some embodiments of the present invention is shown.

[0025] Figure 7B A schematic diagram of a silicon nitride film deposited at an energy density of 19200 W·s·Torr after wet etching at different powers, RF times and pressures provided in some embodiments of the present invention is shown.

[0026] Figure 7C A schematic diagram of a silicon nitride film deposited at an energy density of 96000 W·s·Torr after wet etching at different powers, RF times and pressures provided in some embodiments of the present invention is shown. DETAILED DESCRIPTION

[0027] 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.

[0028] 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.

[0029] 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.

[0030] 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.

[0031] As mentioned above, in the semiconductor field, the thin film deposition and conformality (step coverage) of semiconductor devices before and after thin film etching are crucial for the processing of semiconductor devices. The current prior art in this field uses a high-frequency plasma generator (>60 MHz plasma generator) to control the conformality of the thin film wet etching rate (WER), and the matching process pressure range is limited to 4-7 Torr, which has process limitations, and the method is expensive, increasing the manufacturing cost.

[0032] In order to overcome the above-mentioned defects of the prior art, the present invention provides a thin film deposition device for a semiconductor device and a thin film deposition method for a semiconductor device, which can realize a wide range of controllable process parameters (such as pressure / energy), improve the wet etching conformality and step coverage of the thin film, and reduce the processing cost of the semiconductor device.

[0033] In some non-limiting embodiments, the thin film deposition method for the semiconductor device provided in the third aspect of the present invention can be implemented via the thin film deposition device for the semiconductor device provided in the first aspect of the present invention. The thin film deposition device for the semiconductor device can be configured in the semiconductor device provided in the second aspect of the present invention to implement the thin film deposition method for the semiconductor device provided in the third aspect of the present invention. The semiconductor device is configured with a memory and a processor. The memory includes but is not limited to the computer-readable storage medium provided in the fourth aspect of the present invention, on which computer instructions are stored. The processor is connected to the memory and is configured to execute the computer instructions stored on the memory to implement the thin film deposition method for the semiconductor device provided in the third aspect of the present invention.

[0034] First, please refer to Figure 1 . Figure 1 A schematic diagram of a thin film deposition apparatus for a semiconductor device provided according to some embodiments of the present invention is shown.

[0035] like Figure 1As shown, the thin film deposition device for semiconductor devices provided by the first aspect of the present invention may include a reaction chamber 11, a radio frequency generator 12, an adjustable capacitor 13 and a controller (not shown). Here, the controller may be configured as follows: first, the controller may determine the target energy density of the thin film deposition of the semiconductor device. Afterwards, the controller may adjust the capacitance value of the adjustable capacitor 13 according to the target energy density and the radio frequency frequency of the radio frequency generator, so that the deposition power and the deposition pressure in the reaction chamber 11 match the target energy density. After determining the target energy density, the controller may also thin film deposit the semiconductor device based on the process conditions of the target energy density. In this way, the present invention can realize a wide range of controllable process parameters (such as pressure / energy); can improve the wet etching conformality of the thin film (i.e., step coverage); support the use of low-power radio frequency generators, and can reduce processing costs.

[0036] Furthermore, in some embodiments of the present invention, the controller may also determine the target energy density for etching the semiconductor device according to the top conformality and / or sidewall conformality and bottom conformality required by the semiconductor device. In this way, the present invention can flexibly select the target energy density for thin film deposition according to the top conformality and / or sidewall conformality and / or bottom conformality required by the semiconductor device, thereby improving the etching selectivity of the SiN film. Here, the calculation method of conformality is to divide the film thickness of each part by the top film thickness.

[0037] Furthermore, in some embodiments of the present invention, when the sidewall conformality and bottom conformality required by the semiconductor device are both greater than a preset threshold, the controller may determine the target energy density to be 48-80 kW·s·Torr.

[0038] Optionally, the preset thresholds may be 90% for the side wall shape retention and 78% for the bottom shape retention.

[0039] Furthermore, in some embodiments of the present invention, the processor can adjust the capacitance of the adjustable capacitor according to the target energy density, the RF frequency of the RF generator below 60 MHz, and the preset RF time to expand the process window of the deposition power and the deposition pressure. In this way, the present invention can further expand the process window of deposition power and deposition pressure by using a low-power RF generator in conjunction with the adjustable capacitor.

[0040] Furthermore, in some embodiments of the present invention, the RF frequency of the RF generator may be 27 MHz, the process window of the deposition power may be 600-2500 W, and the process window of the deposition pressure may be 6-20 Torr.

[0041] Furthermore, in some embodiments of the present invention, the thin film deposition device may further include an AC filter 14. The filter may adjust the 27 MHz radio frequency emitted by the RF generator to 13.5 MHz. The controller may also be configured to adjust the frequency of the radio frequency via the AC filter according to the target energy density.

[0042] Furthermore, in some embodiments of the present invention, after the above-mentioned semiconductor device is subjected to thin film deposition, the above-mentioned method can also perform wet etching on the semiconductor device on which the above-mentioned thin film is deposited to obtain a thin film with the required top conformality and / or sidewall conformality and / or bottom conformality.

[0043] Please refer to Figure 2 , Figure 2 A schematic diagram of film formation using a four-step cycle method according to some embodiments of the present invention is shown.

[0044] Specifically, if Figure 2 As shown, the above-mentioned four-step cyclic deposition method of thin film can first introduce a precursor, which includes but is not limited to a halogen silane-silicon source and a Purge gas-N source, and perform pressure control. After the precursor is introduced, the method can purge the above-mentioned precursor, stop introducing the halogen silane-silicon source, and continue to introduce the Purge gas-N source and perform pressure control. After the precursor purge is completed, the method can turn on the radio frequency, continuously generate radio frequency plasma, continuously introduce the Purge gas-N source and perform pressure control. After the radio frequency plasma is introduced, the method can perform radio frequency purge, continuously introduce the Purge gas-N source and perform pressure control.

[0045] In other embodiments of the present invention, the above-mentioned thin film deposition may first supply the first gas within a first time period, and chemically adsorb onto the substrate when the first gas is supplied into the reaction space. Afterwards, the above-mentioned method may stop the supply of the first gas within a second time period, and supply a flushing gas into the reaction space to exhaust the remaining first gas in the reaction space from the reactor. Thereafter, the above-mentioned method supplies the second gas into the reaction space, and the thin film layer is formed when the second gas chemically reacts with the first gas chemically adsorbed onto the substrate. Plasma is supplied within the second time period so that the thin film layer can be formed at a set temperature. In other words, the chemical reaction can be carried out at a target temperature. After supplying plasma, the above-mentioned method may stop the supply of the second gas, and supply a flushing gas again so that the remaining second gas is removed from the reactor. In this way, the method can complete the thin film deposition on the substrate.

[0046] Furthermore, in some embodiments of the present invention, the semiconductor device may include a thin film deposition device for the semiconductor device to complete thin film deposition of the semiconductor device. The principle of the thin film deposition device has been described in detail and will not be further elaborated here.

[0047] The working principle of the thin film deposition device of the above-mentioned semiconductor device will be described below in conjunction with some embodiments of the thin film deposition method of semiconductor devices. Those skilled in the art can understand that the embodiments of the thin film deposition method of these semiconductor devices 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 thin film deposition device of the semiconductor device. Similarly, the thin film deposition device of the semiconductor device is also only a non-limiting implementation method provided by the present invention, and does not constitute a limitation on the execution subject of each step in the thin film deposition method of these semiconductor devices.

[0048] Please refer to Figure 1 as well as Figure 3 . Figure 3 A schematic flow chart of a thin film deposition method for a semiconductor device provided according to some embodiments of the present invention is shown.

[0049] like Figure 1 as well as Figure 3 As shown, the thin film deposition method of the semiconductor device can first determine the target energy density of thin film deposition of the semiconductor device. After determining the target energy density, the method can adjust the capacitance value of the adjustable capacitor according to the target energy density and the RF frequency of the RF generator so that the deposition power, RF time and deposition pressure in the reaction chamber match the target energy density. Thereafter, the thin film deposition method can perform thin film deposition on the semiconductor device based on the process conditions of the target energy density.

[0050] Please refer to Figure 4 as well as Figure 5 . Figure 4 A schematic diagram of process control logic provided according to some embodiments of the present invention is shown. Figure 5 Schematic diagrams of etching the sidewall, top and bottom at different energy densities provided according to some embodiments of the present invention are shown.

[0051] like Figure 4 As shown, the thin film deposition device of the semiconductor device can use a 27 MHz RF generator to achieve a wide range of energy density (power × RF time × pressure), so that the film can obtain excellent wet etching conformality within a wide process window. Figure 5As shown, the thin film deposition method of the semiconductor device can control the energy density of the cavity so that the energy density is between 48000 and 80000. In this energy density range, the SiN film has excellent wet etching conformality.

[0052] Please refer to Figure 6A to Figure 6C as well as Figure 7A to Figure 7C , Fig. 6A A schematic cross-sectional view of a silicon nitride film after etching is shown, which is a deposited film under different powers, radio frequency times and pressures, ie, under moderate energy density, according to some embodiments of the present invention. Figure 6B A schematic cross-sectional view of a silicon nitride film after etching is shown, which is a deposited film under different powers, radio frequency times and pressures, ie, under moderate energy density, according to some embodiments of the present invention. Figure 6C A schematic cross-sectional view of a silicon nitride film after etching is shown, which is a deposited film under different powers, radio frequency times and pressures, ie, under moderate energy density, according to some embodiments of the present invention. Fig. 7A A schematic cross-sectional view of a silicon nitride film after etching is shown, which is a deposited film under different powers, radio frequency times and pressures, that is, under too low energy density, according to some embodiments of the present invention. Figure 7B A schematic cross-sectional view of a silicon nitride film after etching is shown, which is a deposited film under different powers, radio frequency times and pressures, that is, under too low energy density, according to some embodiments of the present invention. Figure 7C A schematic cross-sectional view of a silicon nitride film after etching is shown under different powers, radio frequency times and pressures, that is, under an excessively high energy density, according to some embodiments of the present invention.

[0053] like Fig. 6A As shown in the figure, when the power is 800W, the RF time is 5s, the pressure is 12Torr, the energy density is 48000, the DHF is 100:1, and the wet etching is 5min, the side wall conformality is 97% and the bottom conformality is 79%. Figure 6B As shown in the figure, when the power is 2500W, the RF time is 2s, the pressure is 12Torr, the energy density is 60000, the DHF is 100:1, and the wet etching is 5min, the side wall conformality is 93% and the bottom conformality is 81%. Figure 6C As shown in the figure, when the power is 2000W, the RF time is 2s, the pressure is 20Torr, the energy density is 80000, the DHF is 100:1, and the wet etching is 5min, the side wall conformality is 95% and the bottom conformality is 84%. Fig. 7A As shown in the figure, when the power is 800W, the RF time is 2s, the pressure is 10Torr, the energy density is 16000, the DHF is 100:1, and the wet etching is 5min, the side wall conformality is 43% and the bottom conformality is 53%. Figure 7BAs shown in the figure, when the power is 800W, the RF time is 2s, the pressure is 12Torr, the energy density is 19200, the DHF is 100:1, and the wet etching is 5min, the side wall conformality is 67% and the bottom conformality is 91%. Figure 7C As shown in the figure, when the power is 800W, the RF time is 10s, the pressure is 12Torr, the energy density is 96000, the DHF is 100:1, and the wet etching is 5min, the side wall conformality is 149% and the bottom conformality is 145%. When the energy density is too high or too low (energy density <48000 or energy density> When the energy density is moderate (energy density>48000 and energy density<80000), the WER conformality of the thin film deposition is good.

[0054] Compared with the prior art in this field, the present invention can achieve a wide range of controllable process parameters (such as pressure / energy). On this basis, by adjusting the process and controlling the energy density, the etching selectivity of the silicon nitride film can be improved, the wet etching conformality of the film can be improved, and the step coverage of the SiN film after etching can be greatly improved, so that the SiN film can still maintain a step coverage of more than 80% after wet etching, which provides a possibility for further application of SiN film.

[0055] 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.

[0056] 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 thin film deposition device for a semiconductor device, characterized in that: The invention comprises a reaction chamber, a radio frequency generator, an adjustable capacitor and a controller, wherein the controller is configured as follows: Determining a target energy density for thin film deposition on the semiconductor device, wherein the target energy density is the product of a preset deposition power, a preset radio frequency time, and a preset deposition pressure in the reaction chamber; According to the target energy density and the RF frequency of the RF generator, adjusting the capacitance value of the adjustable capacitor so that the deposition power, the RF time and the deposition pressure in the reaction chamber match the target energy density; and Based on the process conditions of the target energy density, thin film deposition is performed on the semiconductor device.

2. The thin film deposition device according to claim 1, characterized in that: The step of determining a target energy density for thin film deposition on the semiconductor device comprises: According to the top conformality and / or sidewall conformality and / or bottom conformality required by the semiconductor device, a target energy density for thin film deposition on the semiconductor device is determined.

3. The thin film deposition device according to claim 2, characterized in that: The step of determining a target energy density for thin film deposition on the semiconductor device according to top conformality and / or sidewall conformality and / or bottom conformality required by the semiconductor device comprises: In response to the sidewall conformality and bottom conformality required by the semiconductor device being greater than a preset threshold, the target energy density is determined to be 48-80 kW·s·Torr.

4. The thin film deposition device according to claim 1, characterized in that: The step of adjusting the capacitance value of the adjustable capacitor according to the target energy density and the radio frequency frequency of the radio frequency generator comprises: According to the target energy density and the radio frequency of the radio frequency generator below 60 MHz, the capacitance value of the adjustable capacitor is adjusted to expand the process window of the deposition power and the deposition pressure.

5. The thin film deposition device according to claim 4, characterized in that: The radio frequency of the radio frequency generator is 27 MHz, the process window of the deposition power is 600-2500 W, and the process window of the deposition pressure is 6-20 Torr.

6. The thin film deposition device according to claim 4, characterized in that: It also includes an AC filter for adjusting the 27 MHz radio frequency emitted by the radio frequency generator to 13.5 MHz. The controller is further configured to: According to the target energy density, the frequency of the radio frequency is adjusted via the AC filter.

7. The thin film deposition device according to claim 2, characterized in that: After performing thin film deposition on the semiconductor device, the thin film deposition apparatus is further configured to: The semiconductor device on which the thin film is deposited is wet-etched to obtain a thin film having the required top conformality, sidewall conformality, and / or bottom conformality.

8. A semiconductor device, characterized in that: The semiconductor device is obtained by thin film deposition using a thin film deposition apparatus for a semiconductor device as claimed in any one of claims 1 to 7.

9. A method for thin film deposition of a semiconductor device, characterized in that: The following steps are involved: Determining a target energy density for thin film deposition of the semiconductor device; According to the target energy density and the radio frequency of the radio frequency generator, adjusting the capacitance value of the adjustable capacitor so that the deposition power, the radio frequency time and the deposition pressure in the reaction chamber match the target energy density; as well as Based on the process conditions of the target energy density, thin film deposition is performed on the semiconductor device.

10. A computer-readable storage medium having computer instructions stored thereon, characterized in that: When the computer instructions are processed and executed, the thin film deposition method for a semiconductor device as claimed in claim 9 is implemented.

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