Device and method for improving vapor phase film deposition thickness stability

Abstract

The invention relates to the technical field of semiconductor manufacturing, in particular to a device and method for improving vapor phase thin film deposition thickness stability, the device comprises a temperature monitoring module, a control module and a heating module, and the temperature monitoring module and the heating module are in communication connection with the control module; wherein the heating module is configured to heat reaction raw materials entering the reactor and generate reaction gas; the temperature monitoring module is configured to obtain the real-time temperature of the reaction gas; and the control module is configured to judge whether the real-time temperature reaches a preset temperature or not, if the real-time temperature is lower than the preset temperature, the heating temperature of the heating module is increased, and if the real-time temperature is higher than the preset temperature, the heating temperature of the heating module is reduced. By monitoring the real-time temperature of the reaction gas in the reactor, the heating temperature of the reaction raw materials is precisely regulated and controlled, so that the temperature of the reaction gas is controllable, the deposition rate of the gas-phase film and the stability of the film thickness are ensured, and the performance of the device is improved.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing technology, and in particular to a device and method for improving the thickness stability of vapor phase thin film deposition. Background Art

[0002] As the size of semiconductor devices and materials continues to decrease, and the aspect ratio of the devices continues to increase, the thin films used in semiconductor materials need to be controlled more on an atomic basis, making atomic layer deposition technology gradually becoming a necessity in the field of microelectronic device manufacturing.

[0003] Atomic layer deposition has inherent advantages over traditional processes such as metal organic chemical vapor deposition (MOCVD) and physical vapor deposition (PVD). It makes full use of surface saturation reactions, has natural thickness control and high stability, and is not very sensitive to changes in temperature and reactant flux. The resulting film has both high purity and high density, is both flat and highly conformal, and can achieve good step coverage even for structures with an aspect ratio of up to 100:1. Atomic layer deposition technology also conforms to the industry's trend towards lower thermal budgets. Most processes can be carried out below 400 degrees Celsius, while traditional chemical vapor deposition processes must be completed above 500 degrees Celsius.

[0004] Atomic layer deposition is a process of alternately passing gaseous precursor pulses into the reactor and chemically adsorbing and reacting on the substrate to form a thin film. Various reactants are separated by supplying inert gas (Ar, N2, etc.), a single atomic layer is deposited, and the thickness is controlled by repeated deposition. Chemical adsorption is a thermal activation process, so there is a minimum temperature for atomic layer deposition. In the range greater than the minimum value, to obtain a stable deposition rate, the system must be kept in an appropriate temperature window.

[0005] When the temperature is not high enough, the relationship between the growth rate and temperature shows the following two trends: (1) The rate at which the substrate adsorbs the precursor (or reacts with the precursor) is slow, and the adsorption cannot reach saturation in a short period of time, or the surface reaction is incomplete. As the temperature rises, the reaction rate gradually accelerates, resulting in an increase in the deposition rate. At this time, the growth rate is an increasing function of temperature; (2) The precursor may condense, and a large amount of precursor condenses on the substrate surface. It cannot be purified by inert gas, causing the amount of precursor participating in the reaction to increase greatly. It is difficult for the system to maintain self-limiting characteristics, and the film growth rate distribution is uneven. As the temperature further decreases, the condensation phenomenon becomes more serious. Under the influence of this factor, the deposition rate is a decreasing function of temperature.

[0006] When the temperature is too high, there are also two trends in the relationship between the growth rate and temperature: (1) the functional groups on the substrate surface may break chemical bonds and decompose, resulting in a gas phase reaction similar to the chemical vapor deposition process. The reaction rate is too fast and difficult to control; (2) the film may desorb due to the high temperature, causing the growth rate of the film to decrease with increasing temperature.

[0007] Therefore, no matter the temperature is too high or too low, all possible adverse factors will destroy the self-limitation of atomic layer deposition, and the entire deposition process is no longer expected, and can only be regarded as a process similar to atomic layer deposition, and its deposition rate may increase or decrease with the increase of temperature. This will lead to uncontrollable deposition rate, and ultimately affect the uniformity, purity and thickness control of the film, and then affect the performance of the device. Summary of the invention

[0008] The purpose of the present invention is to provide a device and method for improving the thickness stability of gas phase thin film deposition, which at least solves the problem that the uncontrollable temperature in the existing atomic layer deposition affects the thickness stability of the thin film.

[0009] To achieve the above object, the present invention provides a device for improving the thickness stability of vapor phase thin film deposition, comprising a temperature monitoring module, a control module and a heating module, wherein the temperature monitoring module and the heating module are respectively connected to the control module in communication; wherein,

[0010] The heating module is configured to heat the reaction materials entering the reactor and generate reaction gas;

[0011] The temperature monitoring module is configured to obtain the real-time temperature of the reaction gas and send it to the control module;

[0012] The control module is configured to determine whether the real-time temperature reaches a preset temperature. If the real-time temperature is lower than the preset temperature, the heating temperature of the heating module is increased; if the real-time temperature is higher than the preset temperature, the heating temperature of the heating module is reduced.

[0013] Optionally, when the control module determines that the difference between the real-time temperature and the preset temperature exceeds 0.05° C., the heating temperature of the heating module is adjusted.

[0014] Optionally, the temperature monitoring module includes at least one temperature sensor.

[0015] Optionally, the temperature monitoring module includes a plurality of temperature sensors respectively connected to the control module for communication, and the control module calculates an average value based on the measurement values ​​of the plurality of temperature sensors as the real-time temperature of the reaction gas.

[0016] Optionally, the system further includes a pressure monitoring module communicatively connected to the control module, wherein the pressure monitoring module is configured to obtain the saturated vapor pressure in the reactor and send it to the control module, and the control module corrects the real-time temperature according to the saturated vapor pressure.

[0017] Optionally, the heating module is a heating belt, and the heating belt is wrapped around the outside of the reaction gas delivery pipeline.

[0018] Based on the same inventive concept, the present invention also provides a device for improving the thickness stability of vapor phase thin film deposition, comprising:

[0019] Providing a heating module, wherein the heating module is configured to heat the reaction materials entering the reactor and generate reaction gas;

[0020] Obtaining the real-time temperature of the reaction gas;

[0021] Determine whether the real-time temperature reaches a preset temperature. If the real-time temperature is lower than the preset temperature, increase the heating temperature of the heating module. If the real-time temperature is higher than the preset temperature, reduce the heating temperature of the heating module.

[0022] Optionally, when the difference between the real-time temperature and the preset temperature exceeds 0.05° C., the heating temperature of the heating module is adjusted.

[0023] Optionally, while obtaining the real-time temperature of the reaction gas, the saturated vapor pressure in the reactor is obtained, and the real-time temperature is corrected according to the saturated vapor pressure.

[0024] Based on the same inventive concept, the present invention also provides a vapor phase thin film deposition device, including the device for improving the thickness stability of vapor phase thin film deposition as described above.

[0025] In the device and method for improving the thickness stability of vapor phase thin film deposition provided by the present invention, at least one of the following beneficial effects is achieved:

[0026] 1) By directly monitoring the real-time temperature of the reaction gas in the reactor, the heating temperature of the reaction raw materials can be precisely controlled, so that the temperature of the reaction gas in the reactor can be controlled, thereby ensuring the deposition rate of the gas phase film and the stability of the film thickness, and improving device performance. In addition, for the same production batch of silicon wafers, the stability of the film thickness of the silicon wafers at different times can also be guaranteed.

[0027] 2) While using the temperature monitoring module to obtain the real-time temperature of the reaction gas in the reactor, the pressure monitoring module is used to obtain the saturated vapor pressure in the reactor to correct the real-time temperature, thereby more accurately regulating the heating temperature of the reaction raw materials. This allows the saturated vapor pressure in the reactor to reach the required process pressure in a shorter time, further improving the stability of the thin film deposition thickness. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Those skilled in the art will appreciate that the accompanying drawings are provided for a better understanding of the present invention and do not constitute any limitation on the scope of the present invention.

[0029] Figure 1 A structural block diagram of a device for improving thickness stability of a vapor phase thin film deposition provided by an embodiment of the present invention;

[0030] Figure 2 A step diagram of a device for improving thickness stability of vapor phase thin film deposition provided by one embodiment of the present invention.

[0031] In the attached figure:

[0032] 1- Temperature monitoring module; 2- Control module; 3- Heating module; 4- Pressure monitoring module. DETAILED DESCRIPTION

[0033] In order to make the purpose, advantages and features of the present invention clearer, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the accompanying drawings are in a very simplified form and use non-precise proportions, which are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention. In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, please refer to the accompanying drawings. It should be noted that the structure, proportion, size, etc. illustrated in the drawings of this specification are only used to match the content disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention. Any modification of the structure, change in the proportional relationship or adjustment of the size, under the same or similar conditions as the effects that can be produced by the present invention and the purposes that can be achieved, should still fall within the scope of the technical content disclosed by the present invention.

[0034] As used in the present invention, the singular forms "one", "an", and "the" include plural objects, unless the content clearly indicates otherwise. As used in the present invention, the term "or" is generally used in a sense that includes "and / or", unless the content clearly indicates otherwise. As used in the present invention, the term "several" is generally used in a sense that includes "at least one", unless the content clearly indicates otherwise. As used in the present invention, the term "at least two" is generally used in a sense that includes "two or more", unless the content clearly indicates otherwise. In addition, the terms "first", "second", and "third" are used only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first", "second", and "third" may explicitly or implicitly include one or at least two of the features.

[0035] In the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "fixed" 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 an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] Please refer to Figure 1 The embodiment of the present invention provides a device for improving the thickness stability of vapor phase thin film deposition, comprising a temperature monitoring module 1, a control module 2 and a heating module 3, wherein the temperature monitoring module 1 and the heating module 3 are respectively connected to the control module 2 in communication; wherein,

[0037] The heating module 3 is configured to heat the reaction materials entering the reactor and generate reaction gas;

[0038] The temperature monitoring module 1 is configured to obtain the real-time temperature of the reaction gas in the reactor and send it to the control module 2;

[0039] The control module 2 is configured to determine whether the real-time temperature reaches the preset temperature. If the real-time temperature is lower than the preset temperature, the heating temperature of the heating module 3 is increased; if the real-time temperature is higher than the preset temperature, the heating temperature of the heating module 3 is reduced.

[0040] The present invention directly monitors the real-time temperature of the reaction gas in the reactor to precisely control the heating temperature of the reaction raw materials entering the reactor, thereby making the temperature of the reaction gas in the reactor controllable, thereby ensuring the deposition rate of the atomic layer and the stability of the film thickness, and improving the device performance. In addition, for the same production batch of silicon wafers, the stability of the film thickness of the silicon wafers at different times can also be guaranteed.

[0041] In this embodiment, the reaction raw materials may be solid, liquid or gas, and the present invention does not impose any limitation on this.

[0042] Preferably, when the control module 2 determines that the difference between the real-time temperature and the preset temperature exceeds 0.05°C, the heating temperature of the heating module 3 is adjusted. In other words, the sensitivity of the temperature adjustment of the reaction gas is 0.05°C. When the difference between the real-time temperature and the preset temperature does not exceed 0.05°C, it means that the real-time temperature is very close to the required preset temperature. At this time, there is no need to adjust the heating temperature of the heating module 3. Only when the difference between the real-time temperature and the preset temperature exceeds 0.05°C, can the control module 2 be triggered to adjust the heating temperature of the heating module 3. Of course, the setting of the preset temperature and the control difference between the real-time temperature and the preset temperature can be adjusted according to actual needs, and the present invention does not limit this.

[0043] Optionally, the temperature monitoring module 1 includes at least one temperature sensor. The temperature sensor can obtain the real-time temperature of the reaction gas in the reactor and send it to the control module 2. The present invention does not limit its specific model, and the existing temperature sensor on the market can be used as long as it meets the test requirements.

[0044] As a preferred example of this embodiment, the temperature monitoring module 1 includes a plurality of temperature sensors respectively connected to the control module 2 in communication, and the control module 2 calculates the average value according to the measured values ​​of the plurality of temperature sensors as the real-time temperature of the reaction gas. By respectively collecting the real-time temperature of the reaction gas in the reactor through a plurality of temperature sensors and calculating the average value, the measurement accuracy of the real-time temperature can be improved, thereby achieving more accurate temperature control.

[0045] Further, the system also includes a pressure monitoring module 4 that is connected to the control module 2 in communication. The pressure monitoring module 4 is configured to obtain the saturated vapor pressure in the reactor and send it to the control module 2, and the control module 2 corrects the real-time temperature according to the saturated vapor pressure. It should be understood that the size of the saturated vapor pressure in the reactor will also affect the uniformity of the film deposition thickness, and according to the ideal gas state equation, when the saturated vapor pressure in the reactor is known, the actual temperature of the reaction gas in the reactor can also be calculated. Therefore, while using the temperature monitoring module 1 to obtain the real-time temperature of the reaction gas in the reactor, the saturated vapor pressure in the reactor is also obtained by the pressure monitoring module 4 to correct the obtained real-time temperature, and then the heating temperature of the reaction raw materials is more accurately regulated, so that the saturated vapor pressure in the reactor can reach the required process pressure in a shorter time, and the stability of the film deposition thickness is further improved. The pressure monitoring module 4 can use the existing pressure sensor on the market, and the present invention does not limit its specific model, as long as it meets the test requirements.

[0046] In this embodiment, the heating module 3 is a heating belt, which is wrapped around a delivery pipeline for the reaction gas. The delivery pipeline is connected to the reactor and is used to deliver the reaction gas to the reactor.

[0047] Based on the same inventive concept, an embodiment of the present invention further provides a method for improving the thickness stability of vapor phase thin film deposition, comprising:

[0048] S1. providing a heating module, wherein the heating module is configured to heat the reaction raw materials entering the reactor and generate reaction gas;

[0049] S2, obtaining the real-time temperature of the reaction gas in the reactor;

[0050] S3. Determine whether the real-time temperature reaches the preset temperature. If the real-time temperature is lower than the preset temperature, increase the heating temperature of the heating module. If the real-time temperature is higher than the preset temperature, reduce the heating temperature of the heating module.

[0051] Preferably, when the difference between the real-time temperature and the preset temperature exceeds 0.05° C., the heating temperature of the heating module is adjusted.

[0052] Preferably, while obtaining the real-time temperature of the reaction gas in the reactor, the saturated vapor pressure in the reactor is also obtained, and the real-time temperature is corrected according to the saturated vapor pressure.

[0053] Based on the same inventive concept, an embodiment of the present invention further provides a vapor phase thin film deposition device, including the device for improving the thickness stability of vapor phase thin film deposition as described above.

[0054] In summary, the embodiments of the present invention provide a device and method for improving the stability of the thickness of the vapor phase thin film deposition. By monitoring the real-time temperature of the reaction gas in the reactor, the heating temperature of the reaction raw materials entering the reactor is precisely controlled, so that the temperature of the reaction gas in the reactor is controllable, thereby ensuring the deposition rate of the vapor phase thin film and the stability of the film thickness, and improving the performance of the device. In addition, while using the temperature monitoring module to obtain the real-time temperature of the reaction gas in the reactor, the saturated vapor pressure in the reactor is obtained through the pressure monitoring module to correct the obtained real-time temperature, and then the heating temperature of the reaction raw materials is more accurately controlled, so that the saturated vapor pressure in the reactor can reach the required process pressure in a shorter time, further improving the stability of the film deposition thickness.

[0055] The above description is only a description of the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any changes and modifications made by a person skilled in the art in the field of the present invention based on the above disclosure are within the scope of protection of the present invention. Obviously, a person skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations fall within the scope of the present invention and its equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A device for improving the thickness stability of vapor phase thin film deposition, characterized in that: It includes a temperature monitoring module, a control module and a heating module, wherein the temperature monitoring module and the heating module are respectively connected to the control module in communication; wherein, The heating module is configured to heat the reaction materials entering the reactor and generate reaction gas; The temperature monitoring module is configured to obtain the real-time temperature of the reaction gas and send it to the control module; The control module is configured to determine whether the real-time temperature reaches a preset temperature. If the real-time temperature is lower than the preset temperature, the heating temperature of the heating module is increased; if the real-time temperature is higher than the preset temperature, the heating temperature of the heating module is reduced.

2. The device for improving the thickness stability of vapor phase thin film deposition according to claim 1, characterized in that: When the control module determines that the difference between the real-time temperature and the preset temperature exceeds 0.05° C., the heating temperature of the heating module is adjusted.

3. The device for improving the thickness stability of vapor phase thin film deposition according to claim 1 or 2, characterized in that: The temperature monitoring module includes at least one temperature sensor.

4. The device for improving the thickness stability of vapor phase thin film deposition according to claim 3, characterized in that: The temperature monitoring module includes a plurality of temperature sensors respectively connected to the control module for communication. The control module calculates an average value according to the measured values ​​of the plurality of temperature sensors as the real-time temperature of the reaction gas.

5. The device for improving the thickness stability of vapor phase thin film deposition according to claim 1, characterized in that: The system further comprises a pressure monitoring module in communication with the control module, wherein the pressure monitoring module is configured to obtain the saturated vapor pressure in the reactor and send the obtained pressure to the control module, and the control module corrects the real-time temperature according to the saturated vapor pressure.

6. The device for improving the thickness stability of vapor phase thin film deposition according to claim 1, characterized in that: The heating module is a heating belt, and the heating belt is wrapped outside the conveying pipeline of the reaction gas.

7. A method for improving the thickness stability of a vapor phase thin film deposition, characterized in that: include: Providing a heating module, wherein the heating module is configured to heat the reaction materials entering the reactor and generate reaction gas; Obtaining the real-time temperature of the reaction gas; Determine whether the real-time temperature reaches a preset temperature. If the real-time temperature is lower than the preset temperature, increase the heating temperature of the heating module. If the real-time temperature is higher than the preset temperature, reduce the heating temperature of the heating module.

8. The method for improving thickness stability of vapor phase thin film deposition according to claim 7, characterized in that: When the difference between the real-time temperature and the preset temperature exceeds 0.05° C., the heating temperature of the heating module is adjusted.

9. The method for improving the thickness stability of vapor phase thin film deposition according to claim 7 or 8, characterized in that: When the real-time temperature of the reaction gas is obtained, the saturated vapor pressure in the reactor is obtained, and the real-time temperature is corrected according to the saturated vapor pressure.

10. A vapor phase thin film deposition device, characterized in that: The invention comprises a device for improving thickness stability of vapor phase thin film deposition according to any one of claims 1 to 6.

Images