Gas detection method and device applied to semiconductor manufacturing

Abstract

The invention provides a gas detection method and device applied to semiconductor manufacturing, in the invention, a gas mixing system is designed, various gases can be mixed through the gas mixing system, and due to the fact that different gases can generate heat effects on corresponding gases after being irradiated by infrared rays with corresponding frequencies, the different gases can generate heat effects on the corresponding gases, so that the gas detection efficiency is improved. According to the principle, the mixed gas which is not irradiated by the infrared light rays is shot, and then the mixed gas is irradiated by the infrared light rays with different frequencies, so that comparison images before and after the irradiation of the phosphine gas can be respectively obtained; according to the present invention, the positions of the phosphine and the hydrogen in the mixed gas in the image can be distinguished through the comparison and the comparison image before and after the hydrogen irradiation, such that the mixing ratio of the mixed gas can be determined, and the mixing ratio of the mixed gas can be detected in real time so as to provide the support for the subsequent control so as to easily improve the yield.

Description

Technical Field

[0001] The present application relates to the field of semiconductor manufacturing technology, and in particular, to a gas detection method and device used in semiconductor manufacturing. Background Art

[0002] In CVD (Chemical Vapor Deposition) equipment, the mixed gas commonly used is a mixed gas of phosphine and hydrogen, wherein hydrogen exists as a gas to dilute phosphine. When performing the chemical vapor deposition process, the proportion of phosphine in the mixed gas needs to meet certain requirements before normal operation. Too high or too low a proportion of phosphine in the mixed gas will affect the yield. In the prior art, a flow control valve is usually used to control the mixing ratio of phosphine and hydrogen. Such a mixing method cannot achieve precise control, and when the mixing ratio cannot meet the requirements, it cannot be determined in time, resulting in a reduction in the yield. Summary of the invention

[0003] In view of this, an embodiment of the present application provides a gas detection method and device applied in semiconductor manufacturing to improve the yield rate in the semiconductor manufacturing process.

[0004] In a first aspect, an embodiment of the present application provides a gas detection method used in semiconductor manufacturing, the gas detection method is used to detect whether the ratio of phosphine gas and hydrogen gas in a gas mixing tank that provides mixed gas for chemical vapor deposition equipment meets the requirements, the gas mixing tank is provided with a first filter that allows infrared wavelengths within a preset range of the absorption peak of phosphine gas to infrared light to pass through, a second filter that allows infrared wavelengths within a preset range of the absorption peak of hydrogen gas to infrared light to pass through, a first infrared light source blocked by the first filter, a second infrared light source blocked by the second filter, and a temperature sensor, two infrared cameras are provided outside the gas mixing tank, the two infrared cameras are provided on the same side of the gas mixing tank, and are arranged horizontally adjacent, a positioning object is provided on the gas mixing tank, and the gas detection method includes: Controlling the two infrared cameras to simultaneously photograph the gas mixing tank according to a preset cycle to obtain a first infrared image photographed by the first infrared camera and a second infrared image photographed by the second infrared camera, and controlling the temperature sensor to collect the current temperature in the gas mixing tank; Controlling the first infrared light source to emit infrared light to obtain a third infrared image captured by the first infrared camera, and controlling the second infrared light source to emit infrared light at a preset time interval to obtain a fourth infrared image captured by the second infrared camera; Taking the gray value corresponding to the temperature as a threshold, performing binarization processing on the first to fourth infrared images respectively to obtain a first binary image corresponding to the first infrared image, a second binary image corresponding to the second infrared image, a third binary image corresponding to the third infrared image, and a fourth binary image corresponding to the fourth infrared image; The first binary image and the third binary image are compared respectively, and for the second binary image and the fourth binary image, a first region in the third binary image having a different pixel value from that in the first binary image is marked by a first mark to obtain a first marked image, and a second region in the fourth binary image having a different pixel value from that in the second binary image is marked by a second mark to obtain a second marked image; Taking the position of the positioning object in the marking image as a cutting reference, the first marking image and the second marking image are cut respectively to obtain a third marking image and a fourth marking image with the same length from the positioning object and the same size; According to the number of first marks in the third mark image and the number of second marks in the fourth mark image, it is determined whether the gas mixing ratio in the gas mixing tank meets the requirements.

[0005] Optionally, determining whether the gas mixing ratio in the gas mixing tank meets the requirement according to the number of first marks in the third mark image and the number of second marks in the fourth mark image includes: calculating a ratio of the number of first marks in the third marked image to the number of second marks in the fourth marked image; When the ratio is within a first preset ratio range, it is determined that the gas mixing ratio in the gas mixing tank meets the requirement; When the ratio exceeds the first preset ratio range, it is determined that the gas mixing ratio in the gas mixing tank does not meet the requirement.

[0006] Optionally, when the ratio exceeds the first preset ratio range, the method further includes: When the ratio exceeds the first preset ratio range and does not fall into the second preset ratio range, the flow rate of the hydrogen gas is controlled according to the ratio.

[0007] Optionally, when the ratio exceeds the first preset ratio range, the method further includes: When the ratio falls into the second preset ratio range, the hydrogen supply cylinder is controlled to stop supplying the hydrogen gas, the phosphine supply cylinder is controlled to stop supplying the phosphine gas, and the gas mixing tank is controlled to stop providing the mixed gas to the chemical vapor deposition equipment.

[0008] Optionally, the method further comprises: Calculating a first distance between any two pixels in the third marked image corresponding to the first mark, and calculating a second distance between any two pixels in the fourth marked image corresponding to the second mark; Calculating a mean square error of a distance set consisting of the first distance and the second distance; When the mean square error is less than or equal to a preset mean square error, it is determined that the gas in the gas mixing tank is uniformly mixed; When the mean square error is greater than the preset mean square error, it is determined that the gas in the gas mixing tank is not mixed uniformly.

[0009] Optionally, when the mean square error is greater than the preset mean square error, the method further includes: The disturbance device in the gas mixing tank is controlled to perform disturbance.

[0010] Optionally, a first delivery pipeline is provided between a phosphine supply cylinder for providing the phosphine gas and the gas mixing tank, and between a hydrogen supply cylinder for providing the hydrogen gas, and a second delivery pipeline is provided between the gas mixing tank and the chemical vapor deposition equipment; One end of the first delivery pipeline and the second delivery pipeline are respectively connected to the exhaust pipeline, and the other end is connected to the purge pipeline.

[0011] In a second aspect, an embodiment of the present application provides a gas detection device used in semiconductor manufacturing, wherein the gas detection device is used to detect whether the ratio of phosphine gas and hydrogen gas in a gas mixing tank that provides mixed gas for chemical vapor deposition equipment meets the requirements, and the gas mixing tank is provided with a first filter that allows infrared wavelengths within a preset range of the absorption peak of phosphine gas to infrared light to pass through, a second filter that allows infrared wavelengths within a preset range of the absorption peak of hydrogen gas to infrared light to pass through, a first infrared light source blocked by the first filter, a second infrared light source blocked by the second filter, and a temperature sensor, two infrared cameras are provided outside the gas mixing tank, the two infrared cameras are provided on the same side of the gas mixing tank, and are arranged horizontally adjacent to each other, a positioning object is provided on the gas mixing tank, and the gas detection device includes: A first shooting unit is used to control the two infrared cameras to simultaneously shoot the gas mixing tank according to a preset cycle, obtain a first infrared image taken by the first infrared camera and a second infrared image taken by the second infrared camera, and control the temperature sensor to collect the current temperature in the gas mixing tank; a second shooting unit, configured to control the first infrared light source to emit infrared light to obtain a third infrared image captured by the first infrared camera, and to control the second infrared light source to emit infrared light at a preset time interval to obtain a fourth infrared image captured by the second infrared camera; A processing unit, configured to perform binarization processing on the first to fourth infrared images respectively with the gray value corresponding to the temperature as a threshold value, so as to obtain a first binary image corresponding to the first infrared image, a second binary image corresponding to the second infrared image, a third binary image corresponding to the third infrared image, and a fourth binary image corresponding to the fourth infrared image; a marking unit, configured to compare the first binary image and the third binary image respectively, and to perform a first marking on a first region in the third binary image having a different pixel value from that in the first binary image, to obtain a first marked image, and to perform a second marking on a second region in the fourth binary image having a different pixel value from that in the second binary image, to obtain a second marked image, for the second binary image and the fourth binary image; a cutting unit, configured to cut the first marking image and the second marking image respectively based on the position of the positioning object in the marking image as a cutting reference, so as to obtain a third marking image and a fourth marking image with the same length from the positioning object and the same size; A judging unit is used to determine whether the gas mixing ratio in the gas mixing tank meets the requirements according to the number of first marks in the third mark image and the number of second marks in the fourth mark image.

[0012] Optionally, the judging unit is used to determine whether the gas mixing ratio in the gas mixing tank meets the requirement according to the number of first marks in the third mark image and the number of second marks in the fourth mark image, comprising: calculating a ratio of the number of first marks in the third marked image to the number of second marks in the fourth marked image; When the ratio is within a first preset ratio range, it is determined that the gas mixing ratio in the gas mixing tank meets the requirement; When the ratio exceeds the first preset ratio range, it is determined that the gas mixing ratio in the gas mixing tank does not meet the requirement.

[0013] Optionally, the gas detection device further includes A control unit is used to control the flow rate of the hydrogen gas according to the ratio when the ratio exceeds the first preset ratio range and does not fall into the second preset ratio range.

[0014] The technical solution provided by the embodiments of the present application may have the following beneficial effects: In the present application, a gas mixing system is designed, through which multiple gases can be mixed. Since different gases can produce a thermal effect on the corresponding gas after being irradiated with infrared light of corresponding frequencies, the temperature of the gas molecules changes. According to this principle, the mixed gas before being irradiated with infrared light is first photographed, and then the mixed gas is successively irradiated with infrared light of different frequencies. In this way, the comparison images before and after the irradiation of phosphine gas and the comparison images before and after the irradiation of hydrogen can be obtained respectively. The positions of phosphine and hydrogen in the mixed gas in the image can be distinguished by comparison, and then the mixing ratio of the mixed gas can be determined. The mixing ratio of the mixed gas can be detected in real time in the above manner to provide support for subsequent control, thereby helping to improve the yield rate.

[0015] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 A schematic diagram of a flow chart of a gas detection method applied in semiconductor manufacturing provided in an embodiment of the present application; Figure 2 A schematic diagram of the structure of a gas mixing system provided in an embodiment of the present application; Figure 3 A schematic diagram of the structure of a gas detection device used in semiconductor manufacturing provided in an embodiment of the present application. DETAILED DESCRIPTION

[0018] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0019] When infrared light irradiates a mixed gas, part of the infrared light will be absorbed by the gas molecules, and part will be reflected or scattered. This interaction between radiation and matter will cause changes in the intensity of the infrared light. In addition, when infrared light irradiates a mixed gas, it will also produce a certain thermal effect. Although this thermal effect is relatively small, it is enough to cause a slight change in the temperature of the gas molecules, thereby changing the intensity of the infrared radiation emitted outward. Infrared imaging equipment captures these radiation changes caused by infrared light irradiation (including direct reflection, scattering, and radiation changes caused by thermal effects) and converts them into electrical signals for processing, ultimately forming a visible infrared image.

[0020] Based on the above principle, two identical infrared light sources are prepared and blocked by two shading sheets respectively. One shading sheet only allows the infrared light corresponding to the absorption peak of phosphine to pass through, and the other only allows the infrared light corresponding to the absorption peak of hydrogen to pass through. The two light sources irradiate the mixed gas successively, so that different gases can produce thermal effects successively, so that the infrared imaging equipment can capture the corresponding gas location and area, and then determine the mixing ratio of the mixed gas.

[0021] Figure 1 A flow chart of a gas detection method used in semiconductor manufacturing provided in an embodiment of the present application, the gas detection method is used to detect whether the ratio of phosphine gas and hydrogen gas in a gas mixing tank that provides mixed gas for chemical vapor deposition equipment meets the requirements, the gas mixing tank is provided with a first filter that allows infrared wavelengths within a preset range from the absorption peak of phosphine gas to infrared light to pass, a second filter that allows infrared wavelengths within a preset range from the absorption peak of hydrogen gas to infrared light to pass, a first infrared light source blocked by the first filter, a second infrared light source blocked by the second filter, and a temperature sensor, two infrared cameras are provided outside the gas mixing tank, the two infrared cameras are provided on the same side of the gas mixing tank, and are arranged horizontally adjacent to each other, and a positioning object is provided on the gas mixing tank, such as Figure 1As shown, the gas detection method comprises the following steps: Step 101, controlling the two infrared cameras to simultaneously photograph the gas mixing tank according to a preset cycle, obtaining a first infrared image photographed by the first infrared camera and a second infrared image photographed by the second infrared camera, and controlling the temperature sensor to collect the current temperature in the gas mixing tank.

[0022] Step 102: Control the first infrared light source to emit infrared light to obtain a third infrared image taken by the first infrared camera, and control the second infrared light source to emit infrared light at a preset time interval to obtain a fourth infrared image taken by the second infrared camera.

[0023] Step 103: Taking the grayscale value corresponding to the temperature as a threshold, binarize the first infrared image to the fourth infrared image respectively to obtain a first binary image corresponding to the first infrared image, a second binary image corresponding to the second infrared image, a third binary image corresponding to the third infrared image, and a fourth binary image corresponding to the fourth infrared image.

[0024] Step 104: respectively compare the first binary image and the third binary image, and for the second binary image and the fourth binary image, perform a first marking on a first region (i.e., each pixel point) in the third binary image having a different pixel value from that in the first binary image to obtain a first marked image, and perform a second marking on a second region (i.e., each pixel point) in the fourth binary image having a different pixel value from that in the second binary image to obtain a second marked image.

[0025] Step 105 : Taking the position of the positioning object in the marking image as a cutting reference, the first marking image and the second marking image are cut respectively to obtain a third marking image and a fourth marking image with the same length from the positioning object and the same size.

[0026] Step 106: Determine whether the gas mixing ratio in the gas mixing tank meets the requirements according to the number of first marks in the third mark image and the number of second marks in the fourth mark image.

[0027] Specifically, Figure 2 A schematic diagram of a gas mixing system provided in an embodiment of the present application is shown in FIG. Figure 2 As shown, the gas mixing system includes a phosphine supply gas cylinder and a hydrogen supply gas cylinder, the phosphine supply gas cylinder and the hydrogen supply gas cylinder are respectively connected to the gas mixing tank through different first delivery pipelines, and the gas mixing tank is provided with two sets of infrared generators ( Figure 2 not shown) and a temperature sensor ( Figure 2), any one set of infrared generators includes an infrared light source ( Figure 2 Not shown) and filters ( Figure 2 ), wherein the first filter is a filter that allows infrared light in a first wavelength range to pass through, and the second filter is a filter that allows infrared light in a second wavelength range to pass through, the first wavelength range includes wavelengths within a preset range from the absorption peak of phosphine to infrared light, and the second wavelength range includes wavelengths within a preset range from the absorption peak of hydrogen to infrared light, and the infrared light emitted by the infrared light source is irradiated to the inside of the gas mixing tank through the filter, and two infrared cameras are arranged outside the gas mixing tank, the two infrared cameras are arranged on the same side of the gas mixing tank, and are arranged horizontally adjacent to each other, the shooting parameters of the two infrared cameras are the same, and the two infrared cameras and the temperature sensor are connected to the processor ( Figure 2 The gas mixing tank is provided with a positioning object, and the gas mixing tank connects the mixed gas with the chemical vapor deposition equipment through a second delivery pipeline. The first delivery pipeline and the second delivery pipeline are both provided with a manual diaphragm valve, a pneumatic diaphragm valve, a flow control valve and a one-way valve.

[0028] The phosphine gas supply cylinder is used to provide phosphine gas, and the hydrogen gas supply cylinder is used to provide hydrogen gas. The hydrogen gas is used to adjust the concentration of phosphine gas, that is, the mixing ratio of phosphine in the total gas. The first delivery pipeline and the second delivery pipeline are both provided with a manual diaphragm valve, a pneumatic diaphragm valve, a flow control valve and a one-way valve, wherein the manual diaphragm valve allows the user to control the switch of the diaphragm valve manually, and the pneumatic diaphragm valve allows the user to control the switch of the diaphragm valve by electrical control. The flow control valve is used to adjust the flow of gas in the pipeline, and the one-way valve can only allow the gas to flow in one direction. The gas mixing tank is provided with a disturbance device for disturbing the gas so that the phosphine gas and the hydrogen gas are mixed. Two sets of infrared generators and a temperature sensor are also provided in the gas mixing tank. Each set of infrared generators includes an infrared light source and a filter. The infrared light source is used to emit infrared light to irradiate the mixed gas, and the filter is used to filter the infrared light so that infrared light of a specific frequency can irradiate to the mixed gas, wherein the wavelength allowed to be emitted by the first filter is a wavelength within a preset range from the absorption peak of phosphine, for example, when the absorption peak of the phosphine gas is between 200 and 300 nanometers, the wavelength range allowed to be emitted by the first filter may be 180 to 320 nanometers, and the wavelength allowed to be emitted by the second filter is a wavelength within a preset range from the absorption peak of hydrogen, for example, when the absorption peak of hydrogen is between 1900 and 3000 nanometers, the wavelength range allowed to be emitted by the second filter may be 1800 to 3100 nanometers, when the infrared light passes through the first filter, the temperature of the phosphine gas increases due to the absorption of the infrared light, while the temperature of the hydrogen gas remains unchanged, when the infrared light passes through the second filter, the temperature of the hydrogen gas increases due to the absorption of the infrared light, while the temperature of the phosphine gas remains unchanged, and through the change in temperature, the position and area (i.e., pixel point) occupied by the phosphine gas and the hydrogen gas can be determined from the infrared image, and then the mixing ratio of the phosphine in the mixed gas can be determined. In order to obtain infrared images, it is also necessary to set up infrared cameras on the same side outside the gas mixing tank and set them horizontally adjacent to each other. The shooting parameters of the two infrared cameras are the same, which can ensure that the two infrared cameras can capture the same area, thus laying the foundation for subsequent comparison.

[0029] In the process of the gas mixing system providing mixed gas for chemical vapor deposition equipment, in order to be able to determine in real time whether the ratio of the mixed gas meets the requirements, two infrared cameras can be controlled to simultaneously shoot the gas mixing tank according to a preset cycle, so as to obtain a first infrared image taken by the first infrared camera and a second infrared image taken by the second infrared camera, and the temperature sensor is controlled to collect the current temperature in the gas mixing tank, so that the phosphine gas and the hydrogen gas have a common temperature comparison basis when compared subsequently, and then the grayscale value corresponding to the temperature obtained by the temperature sensor is used as the threshold.

[0030] Within a preset time after obtaining the first infrared image and the second infrared image, the first infrared emitter is first controlled to emit infrared light to obtain a third infrared image capable of determining the location and area of ​​the phosphine gas, and then the second infrared emitter is controlled to emit infrared light to obtain a fourth infrared image capable of determining the location and area of ​​the hydrogen gas. After obtaining the above four infrared images, the first to fourth infrared images are binarized respectively. For example, after obtaining the first to fourth infrared images, the pixel value corresponding to each pixel point in each infrared image can be determined. Since it is an infrared image, the size of the pixel value and the temperature are directly corresponding. At this time, the first to fourth infrared images can be converted into grayscale images, and then the grayscale value corresponding to the temperature obtained by the temperature sensor is used as a threshold to binarize the first to fourth infrared images, that is, the position greater than the grayscale value corresponding to the temperature is determined as 255, and the position less than the grayscale value corresponding to the temperature is determined as 0, thereby obtaining the first to fourth binary images.

[0031] Then, the two binary images corresponding to the same camera are compared respectively to mark the changed pixels, so as to determine the pixels corresponding to the location of the phosphine gas in the third binary image and the pixels corresponding to the location of the hydrogen gas in the fourth binary image.

[0032] Then, taking the locating object on the gas mixing tank as the cutting reference, the third marking image and the fourth marking image with the same length from the locating object and the same size are obtained from the area included in the first marking image and the second marking image. Since the number of marks can represent the amount of corresponding gas, it is possible to determine whether the gas mixing ratio in the gas mixing tank meets the requirements based on the number of first marks in the third marking image and the number of second marks in the fourth marking image.

[0033] In the present application, a gas mixing system is designed, through which multiple gases can be mixed. Since different gases can produce a thermal effect on the corresponding gas after being irradiated with infrared light of corresponding frequencies, the temperature of the gas molecules changes. According to this principle, the mixed gas before being irradiated with infrared light is first photographed, and then the mixed gas is successively irradiated with infrared light of different frequencies. In this way, the comparison images before and after the irradiation of phosphine gas and the comparison images before and after the irradiation of hydrogen can be obtained respectively. The positions of phosphine and hydrogen in the mixed gas in the image can be distinguished by comparison, and then the mixing ratio of the mixed gas can be determined. The mixing ratio of the mixed gas can be detected in real time in the above manner to provide support for subsequent control, thereby helping to improve the yield rate.

[0034] It should be noted that when performing infrared imaging, the pixel values ​​corresponding to the pixels after imaging at different temperatures are different, that is, there is a conversion relationship between temperature and pixel value. The pixel values ​​corresponding to different temperatures can be determined based on the conversion relationship. After the temperature is obtained through the temperature sensor, the pixel value corresponding to the temperature can be determined through the conversion relationship. Then, the grayscale conversion relationship when performing grayscale processing on the infrared image can be used to convert the pixel value into the corresponding grayscale value, thereby obtaining the grayscale value corresponding to the above-mentioned temperature.

[0035] In a feasible implementation, when executing step 106, the ratio of the number of first marks in the third mark image to the number of second marks in the fourth mark image can be calculated; when the ratio is within a first preset ratio range, it is determined that the gas mixing ratio in the gas mixing tank meets the requirements; when the ratio exceeds the first preset ratio range, it is determined that the gas mixing ratio in the gas mixing tank does not meet the requirements.

[0036] Specifically, each pixel of the third marked image and the fourth marked image is marked and belongs to the same area, so the number of marked pixels in the two marked images can be compared, and the obtained ratio can represent the mixing ratio of phosphine gas and hydrogen gas, thereby determining whether the gas mixing ratio in the gas mixing tank meets the requirements.

[0037] It should be noted that the specific mixing ratio can be set according to specific process requirements and is not specifically limited here.

[0038] In a feasible implementation manner, when the ratio exceeds the first preset ratio range, the method further includes: When the ratio exceeds the first preset ratio range and does not fall into the second preset ratio range, the flow rate of the hydrogen gas is controlled according to the ratio.

[0039] Specifically, when the ratio exceeds the first preset ratio range, when it does not fall into the second preset ratio range, it indicates that the ratio of the mixed gas is deviated, but within the controllable range. At this time, the ratio can be used to determine whether to increase or decrease the flow rate of hydrogen. When controlling the flow rate of hydrogen gas, it can be achieved by controlling the size of the flow control valve so that the ratio of the mixed gas falls within the first preset ratio range.

[0040] In a feasible implementation manner, when the ratio exceeds the first preset ratio range, the method further includes: When the ratio falls into the second preset ratio range, the hydrogen supply cylinder is controlled to stop supplying the hydrogen gas, the phosphine supply cylinder is controlled to stop supplying the phosphine gas, and the gas mixing tank is controlled to stop providing the mixed gas to the chemical vapor deposition equipment.

[0041] Specifically, when the ratio falls into the second preset ratio range, it means that the ratio of the mixed gas is not within the controllable range, which will seriously affect the yield of the semiconductor. In order to avoid serious accidents, it is necessary to control the hydrogen supply cylinder and the phosphine supply cylinder to stop supplying gas, and control the gas mixing tank to stop providing mixed gas to the chemical vapor deposition equipment. Specifically, the pneumatic diaphragm valves on the first delivery pipeline and the second delivery pipeline can be closed to troubleshoot the problem.

[0042] It should be noted that the specific first preset ratio range and the second preset ratio range can be set according to actual needs and are not specifically limited here.

[0043] In a feasible embodiment, in order to determine whether the mixed gas is evenly mixed, the first distance between any two pixels corresponding to the first mark in the third mark image can be calculated, and the second distance between any two pixels corresponding to the second mark in the fourth mark image can be calculated; then the mean square error of the distance set formed by the first distance and the second distance is calculated; when the mean square error is less than or equal to the preset mean square error, it is determined that the gas in the gas mixing tank is evenly mixed; when the mean square error is greater than the preset mean square error, it is determined that the gas in the gas mixing tank is unevenly mixed.

[0044] In a feasible embodiment, when the mean square error is greater than the preset mean square error, the disturbance device in the gas mixing tank is controlled to perform disturbance so as to make the mixed gas uniformly mixed.

[0045] It should be noted that the specific disturbance device and disturbance mode can be set according to the actual mixed gas and are not specifically limited here.

[0046] In one possible embodiment, Figure 2 As shown, a first delivery pipeline is respectively arranged between the phosphine supply cylinder for providing the phosphine gas and the gas mixing tank, and between the hydrogen supply cylinder for providing the hydrogen gas, and a second delivery pipeline is arranged between the gas mixing tank and the chemical vapor deposition equipment; one end of each of the first delivery pipeline and the second delivery pipeline is respectively connected to an exhaust pipeline ( Figure 2 The other end is connected to the purge pipeline ( Figure 2 is connected (not shown).

[0047] Specifically, one end of the first delivery pipeline and the second delivery pipeline are respectively connected to the exhaust pipeline, and the other end is connected to the purge pipeline. When the pipeline needs to be inspected, the gas delivery can be closed by the pneumatic diaphragm valve, and then the gas in the first delivery pipeline and the second delivery pipeline can be discharged through the purge pipeline and the exhaust pipeline.

[0048] Figure 3 A schematic structural diagram of a gas detection device used in semiconductor manufacturing provided in an embodiment of the present application, the gas detection device is used to detect whether the ratio of phosphine gas and hydrogen gas in a gas mixing tank that provides mixed gas for chemical vapor deposition equipment meets the requirements, the gas mixing tank is provided with a first filter that allows infrared wavelengths within a preset range from the absorption peak of phosphine gas to infrared light to pass, a second filter that allows infrared wavelengths within a preset range from the absorption peak of hydrogen gas to infrared light to pass, a first infrared light source blocked by the first filter, a second infrared light source blocked by the second filter, and a temperature sensor, two infrared cameras are provided outside the gas mixing tank, the two infrared cameras are provided on the same side of the gas mixing tank, and are arranged horizontally adjacent to each other, and a positioning object is provided on the gas mixing tank, such as Figure 3 As shown, the gas detection device comprises: The first shooting unit 31 is used to control the two infrared cameras to simultaneously shoot the gas mixing tank according to a preset cycle, obtain a first infrared image taken by the first infrared camera and a second infrared image taken by the second infrared camera, and control the temperature sensor to collect the current temperature in the gas mixing tank; The second shooting unit 32 is used to control the first infrared light source to emit infrared light to obtain a third infrared image captured by the first infrared camera, and to control the second infrared light source to emit infrared light at a preset time interval to obtain a fourth infrared image captured by the second infrared camera; A processing unit 33 is used to perform binarization processing on the first to fourth infrared images respectively with the gray value corresponding to the temperature as a threshold value, so as to obtain a first binary image corresponding to the first infrared image, a second binary image corresponding to the second infrared image, a third binary image corresponding to the third infrared image, and a fourth binary image corresponding to the fourth infrared image; a marking unit 34, configured to compare the first binary image and the third binary image respectively, and for the second binary image and the fourth binary image, to perform a first marking on a first region in the third binary image having a different pixel value from that in the first binary image to obtain a first marked image, and to perform a second marking on a second region in the fourth binary image having a different pixel value from that in the second binary image to obtain a second marked image; A cutting unit 35 is used to cut the first marking image and the second marking image respectively based on the position of the positioning object in the marking image as a cutting reference, so as to obtain a third marking image and a fourth marking image with the same length from the positioning object and the same size; The judging unit 36 ​​is used to determine whether the gas mixing ratio in the gas mixing tank meets the requirement according to the number of the first marks in the third mark image and the number of the second marks in the fourth mark image.

[0049] In a feasible implementation manner, the judgment unit is used to determine whether the gas mixing ratio in the gas mixing tank meets the requirements according to the number of first marks in the third mark image and the number of second marks in the fourth mark image, including: calculating a ratio of the number of first marks in the third marked image to the number of second marks in the fourth marked image; When the ratio is within a first preset ratio range, it is determined that the gas mixing ratio in the gas mixing tank meets the requirement; When the ratio exceeds the first preset ratio range, it is determined that the gas mixing ratio in the gas mixing tank does not meet the requirement.

[0050] In a feasible embodiment, the gas detection device further includes: A control unit is used to control the flow rate of the hydrogen gas according to the ratio when the ratio exceeds the first preset ratio range and does not fall into the second preset ratio range.

[0051] In a feasible embodiment, the control unit is further used for: When the ratio falls into the second preset ratio range, the hydrogen supply cylinder is controlled to stop supplying the hydrogen gas, the phosphine supply cylinder is controlled to stop supplying the phosphine gas, and the gas mixing tank is controlled to stop providing the mixed gas to the chemical vapor deposition equipment.

[0052] In a feasible embodiment, the gas detection device further includes: A first calculating unit, configured to calculate a first distance between any two pixels in the third marked image corresponding to the first mark, and to calculate a second distance between any two pixels in the fourth marked image corresponding to the second mark; A second calculation unit, configured to calculate a mean square error of a distance set consisting of the first distance and the second distance; When the mean square error is less than or equal to a preset mean square error, it is determined that the gas in the gas mixing tank is uniformly mixed; When the mean square error is greater than the preset mean square error, it is determined that the gas in the gas mixing tank is not mixed uniformly.

[0053] In a feasible embodiment, the gas detection device further includes: The disturbance unit is used to control the disturbance device in the gas mixing tank to perform disturbance when the mean square error is greater than the preset mean square error.

[0054] In a feasible embodiment, a first delivery pipeline is respectively provided between the phosphine supply cylinder providing the phosphine gas and the gas mixing tank, and between the hydrogen supply cylinder providing the hydrogen gas, and a second delivery pipeline is provided between the gas mixing tank and the chemical vapor deposition equipment; one end of the first delivery pipeline and the second delivery pipeline are respectively connected to the exhaust pipeline, and the other end is connected to the purge pipeline.

[0055] about Figure 3 The principles of the related content shown can be referred to Figure 1-Figure 2 The explanation of the relevant content will not be repeated in detail here.

[0056] In the embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some communication interfaces, and the indirect coupling or communication connection of the devices or units can be electrical, mechanical or other forms.

[0057] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0058] In addition, each functional unit in the embodiments provided in the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0059] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions to enable a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, and other media that can store program codes.

[0060] It should be noted that similar numbers and letters represent similar items in the following figures. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description and are not to be understood as indicating or implying relative importance.

[0061] Finally, it should be noted that the above-described embodiments are only specific implementation methods of the present application, which are used to illustrate the technical solutions of the present application, rather than to limit them. The protection scope of the present application is not limited thereto. Although the present application is described in detail with reference to the above-mentioned embodiments, ordinary technicians in the field should understand that any technician familiar with the technical field can still modify the technical solutions recorded in the above-mentioned embodiments within the technical scope disclosed in the present application, or can easily think of changes, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application. They should all be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A gas detection method used in semiconductor manufacturing, characterized in that: The gas detection method is used to detect whether the ratio of phosphine gas and hydrogen gas in a gas mixing tank that provides mixed gas for chemical vapor deposition equipment meets the requirements. The gas mixing tank is provided with a first filter that allows infrared wavelengths within a preset range of the absorption peak of phosphine gas to infrared light to pass through, a second filter that allows infrared wavelengths within a preset range of the absorption peak of hydrogen gas to infrared light to pass through, a first infrared light source blocked by the first filter, a second infrared light source blocked by the second filter, and a temperature sensor. Two infrared cameras are provided outside the gas mixing tank, and the two infrared cameras are provided on the same side of the gas mixing tank and are arranged adjacent to each other horizontally. A positioning object is provided on the gas mixing tank. The gas detection method includes: Controlling the two infrared cameras to simultaneously photograph the gas mixing tank according to a preset cycle to obtain a first infrared image photographed by the first infrared camera and a second infrared image photographed by the second infrared camera, and controlling the temperature sensor to collect the current temperature in the gas mixing tank; Controlling the first infrared light source to emit infrared light to obtain a third infrared image captured by the first infrared camera, and controlling the second infrared light source to emit infrared light at a preset time interval to obtain a fourth infrared image captured by the second infrared camera; Taking the gray value corresponding to the temperature as a threshold, performing binarization processing on the first to fourth infrared images respectively to obtain a first binary image corresponding to the first infrared image, a second binary image corresponding to the second infrared image, a third binary image corresponding to the third infrared image, and a fourth binary image corresponding to the fourth infrared image; The first binary image and the third binary image are compared respectively, and for the second binary image and the fourth binary image, a first region in the third binary image having a different pixel value from that in the first binary image is marked by a first mark to obtain a first marked image, and a second region in the fourth binary image having a different pixel value from that in the second binary image is marked by a second mark to obtain a second marked image; Taking the position of the positioning object in the marking image as a cutting reference, the first marking image and the second marking image are cut respectively to obtain a third marking image and a fourth marking image with the same length from the positioning object and the same size; According to the number of first marks in the third mark image and the number of second marks in the fourth mark image, it is determined whether the gas mixing ratio in the gas mixing tank meets the requirements.

2. The gas detection method according to claim 1, characterized in that: The determining, according to the number of first marks in the third mark image and the number of second marks in the fourth mark image, whether the gas mixing ratio in the gas mixing tank meets the requirement includes: calculating a ratio of the number of first marks in the third marked image to the number of second marks in the fourth marked image; When the ratio is within a first preset ratio range, it is determined that the gas mixing ratio in the gas mixing tank meets the requirement; When the ratio exceeds the first preset ratio range, it is determined that the gas mixing ratio in the gas mixing tank does not meet the requirement.

3. The gas detection method according to claim 2, characterized in that: When the ratio exceeds the first preset ratio range, the method further includes: When the ratio exceeds the first preset ratio range and does not fall into the second preset ratio range, the flow rate of the hydrogen gas is controlled according to the ratio.

4. The gas detection method according to claim 3, characterized in that: When the ratio exceeds the first preset ratio range, the method further includes: When the ratio falls into the second preset ratio range, the hydrogen supply cylinder is controlled to stop supplying the hydrogen gas, the phosphine supply cylinder is controlled to stop supplying the phosphine gas, and the gas mixing tank is controlled to stop providing the mixed gas to the chemical vapor deposition equipment.

5. The gas detection method according to claim 1, characterized in that: The method further comprises: Calculating a first distance between any two pixels in the third marked image corresponding to the first mark, and calculating a second distance between any two pixels in the fourth marked image corresponding to the second mark; Calculate the mean square error of a distance set consisting of the first distance and the second distance; When the mean square error is less than or equal to a preset mean square error, it is determined that the gas in the gas mixing tank is uniformly mixed; When the mean square error is greater than the preset mean square error, it is determined that the gas in the gas mixing tank is not mixed uniformly.

6. The gas detection method according to claim 5, characterized in that: When the mean square error is greater than the preset mean square error, the method further includes: The disturbance device in the gas mixing tank is controlled to perform disturbance.

7. The gas detection method according to claim 1, characterized in that: A first delivery pipeline is respectively provided between the phosphine supply cylinder for providing the phosphine gas and the gas mixing tank, and between the hydrogen supply cylinder for providing the hydrogen gas, and a second delivery pipeline is provided between the gas mixing tank and the chemical vapor deposition equipment; One end of the first delivery pipeline and the second delivery pipeline are both communicated with the exhaust pipeline respectively, and the other end thereof are both communicated with the purge pipeline.

8. A gas detection device used in semiconductor manufacturing, characterized in that: The gas detection device is used to detect whether the ratio of phosphine gas and hydrogen gas in a gas mixing tank that provides mixed gas for chemical vapor deposition equipment meets the requirements. The gas mixing tank is provided with a first filter that allows infrared wavelengths within a preset range of the absorption peak of phosphine gas to infrared light to pass through, a second filter that allows infrared wavelengths within a preset range of the absorption peak of hydrogen gas to infrared light to pass through, a first infrared light source blocked by the first filter, a second infrared light source blocked by the second filter, and a temperature sensor. Two infrared cameras are provided outside the gas mixing tank. The two infrared cameras are provided on the same side of the gas mixing tank and are arranged adjacent to each other horizontally. A positioning object is provided on the gas mixing tank. The gas detection device includes: A first shooting unit is used to control the two infrared cameras to simultaneously shoot the gas mixing tank according to a preset cycle, obtain a first infrared image taken by the first infrared camera and a second infrared image taken by the second infrared camera, and control the temperature sensor to collect the current temperature in the gas mixing tank; a second shooting unit, configured to control the first infrared light source to emit infrared light to obtain a third infrared image captured by the first infrared camera, and to control the second infrared light source to emit infrared light at a preset time interval to obtain a fourth infrared image captured by the second infrared camera; A processing unit, configured to perform binarization processing on the first to fourth infrared images respectively with the gray value corresponding to the temperature as a threshold value, so as to obtain a first binary image corresponding to the first infrared image, a second binary image corresponding to the second infrared image, a third binary image corresponding to the third infrared image, and a fourth binary image corresponding to the fourth infrared image; a marking unit, configured to compare the first binary image and the third binary image respectively, and to perform a first marking on a first region in the third binary image having a different pixel value from that in the first binary image, to obtain a first marked image, and to perform a second marking on a second region in the fourth binary image having a different pixel value from that in the second binary image, to obtain a second marked image, for the second binary image and the fourth binary image; a cutting unit, configured to cut the first marking image and the second marking image respectively based on the position of the positioning object in the marking image as a cutting reference, so as to obtain a third marking image and a fourth marking image with the same length from the positioning object and the same size; A judging unit is used to determine whether the gas mixing ratio in the gas mixing tank meets the requirements according to the number of first marks in the third mark image and the number of second marks in the fourth mark image.

9. The gas detection device according to claim 8, characterized in that: The judging unit is used to determine whether the gas mixing ratio in the gas mixing tank meets the requirement according to the number of the first marks in the third mark image and the number of the second marks in the fourth mark image, including: calculating a ratio of the number of first marks in the third marked image to the number of second marks in the fourth marked image; When the ratio is within a first preset ratio range, it is determined that the gas mixing ratio in the gas mixing tank meets the requirement; When the ratio exceeds the first preset ratio range, it is determined that the gas mixing ratio in the gas mixing tank does not meet the requirement.

10. The gas detection device according to claim 9, characterized in that: The gas detection device further comprises: A control unit is used to control the flow rate of the hydrogen gas according to the ratio when the ratio exceeds the first preset ratio range and does not fall into the second preset ratio range.

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