CN120237037B - Silicon carbide groove etching method of semiconductor device - Google Patents
Silicon carbide groove etching method of semiconductor deviceInfo
- Publication number
- CN120237037B CN120237037B CN202510708892.9A CN202510708892A CN120237037B CN 120237037 B CN120237037 B CN 120237037B CN 202510708892 A CN202510708892 A CN 202510708892A CN 120237037 B CN120237037 B CN 120237037B
- Authority
- CN
- China
- Prior art keywords
- fitting
- silicon carbide
- discontinuous
- deviation
- film thickness
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L22/00—Testing or measuring during manufacture or treatment; Reliability measurements, i.e. testing of parts without further processing to modify the parts as such; Structural arrangements therefor
- H01L22/10—Measuring as part of the manufacturing process
- H01L22/12—Measuring as part of the manufacturing process for structural parameters, e.g. thickness, line width, refractive index, temperature, warp, bond strength, defects, optical inspection, electrical measurement of structural dimensions, metallurgic measurement of diffusions
-
- G—PHYSICS
- G06—COMPUTING OR CALCULATING; COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F17/00—Digital computing or data processing equipment or methods, specially adapted for specific functions
- G06F17/10—Complex mathematical operations
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
- H01L21/302—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to change their surface-physical characteristics or shape, e.g. etching, polishing, cutting
- H01L21/306—Chemical or electrical treatment, e.g. electrolytic etching
- H01L21/3065—Plasma etching; Reactive-ion etching
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Manufacturing & Machinery (AREA)
- Power Engineering (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Data Mining & Analysis (AREA)
- Computer Hardware Design (AREA)
- Mathematical Physics (AREA)
- Theoretical Computer Science (AREA)
- Databases & Information Systems (AREA)
- Software Systems (AREA)
- General Engineering & Computer Science (AREA)
- Pure & Applied Mathematics (AREA)
- Plasma & Fusion (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- Mathematical Optimization (AREA)
- Mathematical Analysis (AREA)
- Computational Mathematics (AREA)
- Algebra (AREA)
- Testing Or Measuring Of Semiconductors Or The Like (AREA)
Abstract
本申请涉及半导体器件制造技术领域，具体涉及一种半导体器件的碳化硅沟槽刻蚀方法，该方法包括：对碳化硅晶片进行初次采样选取参考点，在参考点的不同方向上选取多个采样点，测量每个方向上各采样点的膜厚度；得到每个方向的左拟合偏差、右拟合偏差；计算每个方向的间断度，将所有方向区分为间断方向和非间断方向；计算各非间断方向的异样度；计算各间断方向对应左侧、右侧的异样度；确定各非间断方向、各间断方向对应左侧和右侧的拟合阶数；计算碳化硅晶片的均匀度，评估碳化硅晶片的涂胶均匀性，对碳化硅晶片沟槽进行刻蚀。本申请可以动态选取拟合阶数，能够准确检测碳化硅晶片的涂胶均匀性，提高碳化硅沟槽刻蚀的精度和质量。
The present application relates to the field of semiconductor device manufacturing technology, and specifically to a method for etching silicon carbide trenches in semiconductor devices. The method comprises: performing initial sampling on a silicon carbide wafer, selecting a reference point, selecting multiple sampling points in different directions from the reference point, and measuring the film thickness of each sampling point in each direction; obtaining a left fitting deviation and a right fitting deviation in each direction; calculating the discontinuity in each direction, dividing all directions into discontinuous directions and non-discontinuous directions; calculating the heterogeneity of each non-discontinuous direction; calculating the heterogeneity of the left and right sides corresponding to each discontinuous direction; determining the fitting order for each non-discontinuous direction and each discontinuous direction corresponding to the left and right sides; calculating the uniformity of the silicon carbide wafer, evaluating the uniformity of the glue coating on the silicon carbide wafer, and etching the silicon carbide wafer trench. The present application can dynamically select the fitting order, accurately detect the uniformity of the glue coating on the silicon carbide wafer, and improve the accuracy and quality of silicon carbide trench etching.
Description
Technical Field
The application relates to the technical field of semiconductor device manufacturing, in particular to a silicon carbide groove etching method of a semiconductor device.
Background
The silicon carbide MOSFET is a power semiconductor device based on silicon carbide materials and is mainly divided into a plane structure and a groove structure, and when the silicon carbide MOSFET with the groove structure is produced, the uniformity of photoresist glue coating directly influences the size and consistency of the shape of the groove, so that the etching precision and quality of the silicon carbide groove are determined. In the photoetching process, the thickness uniformity of the photoresist layer can be ensured by precisely controlling the coating and developing conditions of the photoresist, so that high-precision pattern transfer is realized in the subsequent etching process.
When the traditional technology detects the glued silicon carbide wafer, the fixed point is generally selected on the wafer, and the thicknesses at different positions on the wafer are obtained in a sampling fitting mode, but in the fitting process, the fitting order is selected, so that the phenomenon of fitting the non-sampled area is caused, the glued thickness of the silicon carbide wafer is detected inaccurately, and the problem of uneven etching depth of the silicon carbide groove is caused.
Disclosure of Invention
In order to solve the above technical problems, a method for etching a silicon carbide trench of a semiconductor device is provided to solve the existing problems.
The application provides a silicon carbide groove etching method for a semiconductor device, which comprises the following steps:
performing primary sampling on a silicon carbide wafer, selecting a reference point, selecting a plurality of sampling points in different directions of the reference point, and measuring the film thickness of each sampling point in each direction;
The maximum film thickness of all sampling points in each direction is recorded as a division point, residual error conditions of film thicknesses of all sampling points at the left side and the right side of the division point in each direction are analyzed to respectively obtain left fitting deviation and right fitting deviation of each direction;
Analyzing the difference conditions among extreme values of all film thicknesses in each uninterrupted direction, and calculating the dissimilarity degree of each uninterrupted direction by combining the average level of the left fitting deviation and the right fitting deviation;
analyzing extreme value difference conditions of film thicknesses at the left side and the right side of the dividing point in each discontinuous direction, and respectively combining left fitting deviation and right fitting deviation to calculate dissimilarity degree corresponding to the left side and dissimilarity degree corresponding to the right side of each discontinuous direction;
based on all dissimilarities, determining fitting orders of each uninterrupted direction and fitting orders of the left side and the right side corresponding to each interrupted direction respectively; respectively performing polynomial fitting on the film thickness in each uninterrupted direction and the film thicknesses at the left side and the right side of the dividing point in each interrupted direction to obtain all fitting curves;
And analyzing the difference condition of the maximum and minimum values in all the fitting curves, calculating the uniformity of the silicon carbide wafer, evaluating the gluing uniformity of the silicon carbide wafer, and etching the grooves of the silicon carbide wafer.
Preferably, the primary sampling of the silicon carbide wafer to select the reference point comprises selecting a plurality of sampling positions from different directions of the mass center of the silicon carbide wafer, and recording the sampling position corresponding to the maximum film thickness of all the sampling positions as the reference point.
Preferably, the obtaining the left fitting deviation and the right fitting deviation of each direction respectively comprises performing linear fitting on film thicknesses of all sampling points positioned at the left side and the right side of the dividing point in each direction, calculating root mean square error, and recording the error as the left fitting deviation and the right fitting deviation respectively.
Preferably, the calculating the discontinuity in each direction includes:
for each direction, obtaining the minimum value of the right fitting deviation and the left fitting deviation, and marking the minimum value as the minimum deviation;
the discontinuity is a ratio of the amount of relative difference to the minimum deviation.
Preferably, the dividing all directions into a discontinuous direction and a non-discontinuous direction includes marking the direction in which the discontinuity degree is larger than a preset first threshold value as the discontinuous direction, and conversely marking the direction as the non-discontinuous direction.
Preferably, the calculating the dissimilarity of each uninterrupted direction includes:
obtaining extreme points of film thicknesses of all sampling points in each direction; calculating the product of the sum of the differences of film thicknesses between all adjacent two extreme points in each uninterrupted direction and the number, and recording the product as the overall fluctuation degree;
the dissimilarity of each uninterrupted direction is the product of the average value and the overall waviness.
Preferably, the calculating the dissimilarity degree corresponding to the left side and the dissimilarity degree corresponding to the right side in each discontinuous direction respectively includes:
respectively counting the number of all extreme points in the film thickness of all sampling points at the left side and the right side of the dividing point in the breaking direction, and respectively recording the number as left number and right number;
The product of the sum of the differences of the film thicknesses between all the adjacent extreme points on the left side of the dividing point in the discontinuous direction and the left quantity is recorded as left fluctuation degree;
The dissimilarity degree on the left side is the product of the left fitting deviation and the left fluctuation degree, and the dissimilarity degree on the right side is the product of the right fitting deviation and the right fluctuation degree.
Preferably, the determining the fitting order of each uninterrupted direction and the fitting order of each uninterrupted direction corresponding to the left side and the right side respectively includes:
First, the Fitting order of non-discontinuous directionsThe calculation formula of (2) is as follows: , wherein, Is the firstDegree of dissimilarity in the non-intermittent direction,In order to preset the first value of the first value,In order to preset the second value of the first value,As an exponential function based on natural constants,And correspondingly, aiming at the dissimilarity degree of each break direction corresponding to the left side and the dissimilarity degree of the right side, obtaining fitting orders of each break direction corresponding to the left side and the right side.
Preferably, the calculating uniformity of the silicon carbide wafer includes:
Obtaining the maximum value and the minimum value of each fitting curve, selecting the maximum value of the maximum values of all fitting curves, and marking the maximum value as a global maximum value;
Uniformity of silicon carbide wafer The calculation formula of (2) is as follows: , wherein, As a consequence of the global maximum,Is the global minimum.
Preferably, the step of evaluating the uniformity of the glue coating of the silicon carbide wafer comprises the step of if the uniformity is larger than a preset second threshold value, non-uniform glue coating of the silicon carbide wafer, otherwise, uniform glue coating of the silicon carbide wafer.
The application has at least the following beneficial effects:
The method comprises the steps of sampling a silicon carbide wafer twice, preliminarily selecting a thicker gluing position, taking the position as a reference point, finely sampling the silicon carbide wafer, measuring the film thickness of each sampling point in different directions, secondly, linearly fitting the film thickness of the sampling points at the two sides of the maximum film thickness in each direction, analyzing the variation condition of fitting residual errors, calculating left fitting deviation and right fitting deviation of each direction, calculating fitting numbers of a plurality of fitting functions respectively after considering the variation trend of the two sides of the maximum film thickness, reflecting the influence condition of fluctuation of the film thickness on glue non-uniformity, further analyzing the difference condition between the left fitting deviation and the right fitting deviation, calculating the discontinuity degree of each direction, taking the similarity condition of the variation of the gluing thickness at the two sides of a dividing point in each direction into a plurality of similar conditions, preliminarily reflecting the possibility of glue non-uniformity, dividing all directions into a discontinuous direction and a non-discontinuous direction by the discontinuity degree, further distinguishing whether the film thickness of all sampling points in each direction is subjected to sectional analysis, calculating the fitting numbers of the subsequent fitting functions respectively, calculating the fitting numbers of the non-discontinuous direction and the film thickness of each sampling point in each direction, calculating the corresponding to the discontinuous direction and the film thickness of each point in each direction, and the discontinuous direction, and obtaining the maximum value by analyzing the difference between the discontinuous direction and the discontinuous direction, the method has the advantages that the fitting effect on the film thickness on the silicon carbide wafer can be improved by dynamically selecting the corresponding fitting order for fitting according to the fluctuation conditions in different directions, the phenomenon of fitting excessively in an un-sampled area is prevented, the uniformity of the silicon carbide wafer is calculated, the glue spreading uniformity of the silicon carbide wafer is evaluated, the silicon carbide wafer grooves are etched, the uniformity of the silicon carbide wafer can be detected more accurately, and the accuracy and quality of the silicon carbide groove etching are improved.
Drawings
The following describes a method for etching a silicon carbide trench of a semiconductor device according to the present application in further detail with reference to the accompanying drawings.
Fig. 1 is a step flowchart of a method for etching a silicon carbide trench of a semiconductor device according to an embodiment of the present application;
fig. 2 is a flowchart of steps of a method for obtaining a discontinuity in each direction according to an embodiment of the present application.
Detailed Description
In order to make the objects, technical solutions and advantages of the present application more apparent, the following describes in further detail a method for etching a silicon carbide trench of a semiconductor device according to the present application with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the application.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.
Referring to fig. 1, a flowchart of a method for etching a silicon carbide trench of a semiconductor device according to an embodiment of the application is shown, the method includes the following steps:
Step 1, a reference point is selected by primary sampling on a silicon carbide wafer, a plurality of sampling points are selected in different directions of the reference point, and film thickness of each sampling point in each direction is measured.
A prepared silicon carbide liner is deposited with a mask layer by vapor phase chemical deposition (CVD) technique, the mask layer may be silicon dioxide or silicon nitride, and the mask layer may transfer a pattern defined in a photolithography process from the photoresist onto the substrate. The photoresist is coated by a photoresist coater, so that the patterns on the mask plate can be accurately transferred to the surface of the substrate, the uniformity of the photoresist coating thickness can influence whether the patterns on the mask plate can be accurately transferred to the surface of the substrate or not in the photoresist coating process of the silicon carbide wafer, and further, the difference of etching rates of silicon carbide grooves is caused, local excessive etching, such as device breakdown or underetching, such as incomplete structure and the like, is caused, and secondly, the stress concentration of a silicon carbide epitaxial layer is caused due to uneven thickness, so that the pressure resistance of a semiconductor device is reduced.
Based on the analysis, sampling points are selected for the silicon carbide wafer to measure the glue coating thickness, and the silicon carbide wafer is sampled twice, specifically:
the primary sampling process comprises the steps of obtaining the mass center of a glued silicon carbide wafer, selecting a plurality of sampling positions from different directions of the mass center, and measuring the film thickness of each sampling position through optical film thickness detection equipment;
in this embodiment, in the eight neighborhood direction of the centroid, a sampling position is selected every 2cm, which is used as another implementation manner, and the practitioner can set the sampling position according to the actual situation.
A second sampling process, namely taking a sampling position corresponding to the maximum film thickness in the first sampling process as a reference point, selecting a plurality of sampling points in different directions of the reference point, measuring the film thicknesses of the positions of all the sampling points through optical film thickness detection equipment, and arranging the film thicknesses of all the sampling points in each direction in the second sampling process according to ascending order of the distance between the film thicknesses of all the sampling points and the reference point to obtain the film thicknesses of all the sampling points in each direction;
in this embodiment, in the eight neighborhood direction of the reference point, a sampling point is selected every 2cm, which is used as another implementation manner, and the practitioner can set the sampling point according to the actual situation.
If the maximum film thickness has a plurality of sampling points, the sampling point closest to the mass center is used as a reference point, and secondly, the position of the maximum value of the glue coating thickness can be rapidly and preliminarily determined through primary sampling, and the position area with the thickest glue coating is sampled and measured again so as to perform more refined detection, so that the uniformity of the position area with the thickest glue coating is analyzed.
Thus, the film thickness of the silicon carbide wafer at all sampling points in each direction in the second sampling process was obtained.
And 2, recording the maximum film thickness of all sampling points in each direction as a division point, analyzing residual error conditions of the film thicknesses of all sampling points at the left side and the right side of the division point in each direction to respectively obtain left fitting deviation and right fitting deviation of each direction, and calculating the discontinuity degree of each direction based on the difference conditions of the left fitting deviation and the right fitting deviation.
The step flow chart of the method for acquiring the discontinuity in each direction provided by the embodiment of the application is shown in fig. 2.
Further, the paste thickness on a silicon carbide wafer may exhibit a certain trend variation along a certain direction, which is very important for the subsequent etching process, because the uniformity of the etching depth depends on the uniformity of the paste thickness. When the glue spreading uniformity of the silicon carbide wafer is detected, the glue spreading thickness of the rest non-sampling areas can be evaluated through a sampling fitting process, so that the change trend of the glue spreading thickness of the non-sampling point corresponding areas is analyzed, the glue spreading uniformity of the silicon carbide wafer is reflected, but in the fitting process, the fitting effect is affected by the selection of the fitting order of the polynomial, and the detection accuracy of the glue spreading uniformity is further affected.
Second, when there is a significant trend in the film thickness of the sampling point, the smaller the influence of the fluctuation thereof causing the unevenness of the paste is compared with the influence of the trend, and when there is no significant trend in the film thickness of the sampling point, the influence of the fluctuation thereof causing the unevenness of the paste is significant. Therefore, the change in film thickness in each direction was analyzed, specifically:
taking the maximum value of film thicknesses of all sampling points in each direction as a division point;
Performing linear fitting on the film thickness of the sampling points positioned on the left side of the dividing points in each direction, calculating root mean square error, and recording the root mean square error as left fitting deviation;
Performing linear fitting calculation on the film thickness of the sampling points positioned on the right side of the dividing points in each direction to obtain root mean square error, and marking the root mean square error as right fitting deviation;
in this embodiment, a least square method is used for linear fitting, where the least square method is a known technique and is not described herein.
The calculation process of the root mean square error is a known technique and will not be described in detail, and the smaller the left and right fitting deviation is, the closer the variation trend of the glue coating thickness on the silicon carbide wafer is to the fitting straight line is, and the smaller the fluctuation of the glue coating thickness is, the smaller the influence on the glue coating non-uniformity is.
Secondly, because the thickness of the glue applied on the silicon carbide wafer after the glue application is applied, the distribution state may be different, that is, the uniformity in a certain local area is higher, and the uniformity in the other local area is lower, so that the distribution states of the film thicknesses on the left and right sides of the silicon carbide wafer in a certain direction are also different. Therefore, when estimating the glue thickness of two sides, it is necessary to use different fitting orders to perform the estimation, so that the discontinuity in each direction is calculated based on the right fitting deviation and the left fitting deviation, specifically:
For each direction, obtaining the minimum value of the right fitting deviation and the left fitting deviation;
calculating the difference between the right fitting deviation and the left fitting deviation, and recording the difference as a relative difference quantity;
Taking the ratio of the relative difference to the minimum value as the discontinuity in each direction;
In this embodiment, the absolute value of the difference between the right fitting deviation and the left fitting deviation is calculated and recorded as the relative difference amount.
The smaller the discontinuity, the closer the distribution state of the glue coating thickness of the sampling points at the left side and the right side of the division point on the silicon carbide wafer is, and the more similar the change of the glue coating thickness is, the more accurate and reliable the glue coating thickness of the sampling points at the left side and the right side of the division point is, otherwise, the larger the discontinuity, the more the possibility of uneven glue coating is possibly generated.
Thus, the degree of discontinuity in each direction is obtained.
Step 3, dividing all directions into a discontinuous direction and a non-discontinuous direction, analyzing the difference condition between extreme values of all film thicknesses in each non-discontinuous direction, calculating the dissimilarity degree of each non-discontinuous direction by combining the average level of the left fitting deviation and the right fitting deviation, analyzing the extreme value difference condition of the film thicknesses at the left side and the right side of the dividing point in each discontinuous direction, and calculating the dissimilarity degree of each discontinuous direction corresponding to the left side and the dissimilarity degree of the right side by respectively combining the left fitting deviation and the right fitting deviation.
Further, when the film thickness of the area corresponding to the non-sampling point on the silicon carbide wafer is estimated by adopting curve fitting, the fitting order is selected to have a larger influence on the fitting effect, so that the detection accuracy of the glue spreading uniformity is further influenced, when the film thickness fluctuation of all sampling points in each direction is smaller, the method has the advantages that the glue spreading of the silicon carbide wafer in the direction is uniform, smaller orders can be adopted, otherwise, the larger the fluctuation change is, obvious fluctuation or trend exists, and the more uneven glue spreading of the silicon carbide wafer in the direction is, and larger orders are needed.
Based on the discontinuity, whether film thickness changes of sampling points on two sides of the dividing point in the direction are consistent or not is evaluated, specifically:
The direction in which the discontinuity is larger than a preset first threshold value is marked as a non-discontinuity direction, and otherwise, the direction is marked as a discontinuity direction;
it should be noted that, the preset first threshold value range is In this embodiment, the first threshold value is preset to be 0.05, and as other embodiments, the practitioner can set the value according to the actual situation.
When the discontinuity is smaller than or equal to a preset threshold, it is indicated that the difference of film thickness variation of sampling points at two sides of the division point in the direction is smaller, and the variation trend is similar.
Secondly, calculating the dissimilarity degree of each uninterrupted direction according to the extreme value change difference of the film thickness of different sampling points in each uninterrupted direction, wherein the dissimilarity degree is specifically as follows:
Obtaining extreme points of film thicknesses of all sampling points in each direction;
In the present embodiment, the extreme points are obtained by a first-order difference method.
Counting the number of all extreme points in each uninterrupted direction, calculating the product of the sum of the differences of film thicknesses between all adjacent two extreme points in each uninterrupted direction and the number, and recording the product as the overall fluctuation degree;
In the present embodiment, the cumulative sum of the absolute values of the differences in film thickness between all adjacent two extreme points in each uninterrupted direction is calculated.
Calculating the average value of the right fitting deviation and the left fitting deviation in each uninterrupted direction, and taking the product of the average value and the integral fluctuation degree as the dissimilarity degree of each uninterrupted direction;
It should be noted that, the greater the overall fluctuation degree, the more severe the fluctuation of the glue coating thickness in the corresponding direction, and the greater the dissimilarity degree, in order to improve the fitting effect on the glue coating thickness, the larger the fitting order should be adopted in the corresponding direction.
Secondly, for film thicknesses of different sampling points in the discontinuous direction, since the film thickness variation difference of two sides of the dividing point is large, the sectional analysis should be performed to obtain the dissimilarity degree of two sides of the dividing point respectively, specifically:
counting the number of extreme points of film thicknesses of all sampling points positioned on the left side of the dividing point in the intermittent direction, and recording the number as the left number;
Counting the number of extreme points of film thicknesses of all sampling points positioned on the right side of the dividing point in the intermittent direction, and recording the number as the right number;
recording the product of the sum of the differences of film thicknesses between all adjacent two extreme points positioned on the left side of the dividing point in the intermittent direction and the left number as left fluctuation degree;
recording the product of the sum of the differences of film thicknesses between all adjacent two extreme points on the right side of the dividing point in the intermittent direction and the right number as a right fluctuation degree;
taking the product of the left fitting deviation and the left fluctuation degree as the dissimilarity degree of the left side corresponding to each discontinuous direction;
taking the product of the right fitting deviation and the right fluctuation degree as the dissimilarity degree of the right side corresponding to each discontinuous direction;
the larger the left fluctuation degree or the right fluctuation degree is, the more severe the fluctuation of the glue coating thickness on the corresponding sequence is, and the larger the obtained left dissimilarity degree or the obtained right dissimilarity degree is, the larger fitting order should be adopted in the subsequent fitting.
Thus, the dissimilarity degree corresponding to different directions is obtained.
And 4, respectively determining fitting orders in each non-discontinuous direction and fitting orders corresponding to the left side and the right side in each discontinuous direction based on all dissimilarities, respectively performing polynomial fitting on film thicknesses in each non-discontinuous direction and film thicknesses at the left side and the right side of the dividing point in each discontinuous direction to obtain all fitting curves, analyzing the difference condition of the maximum value and the minimum value in all the fitting curves, calculating uniformity of a silicon carbide wafer, evaluating glue spreading uniformity of the silicon carbide wafer, and etching grooves of the silicon carbide wafer.
Further, the smaller the fluctuation state of the coating thickness is, the larger the fitting order should be set. The glue coating thickness of different areas on the silicon carbide wafer can be accurately estimated through the dynamic fitting order, so that the fitting order of a polynomial fitting function is determined based on the dissimilarity degree of the uninterrupted direction, and specifically comprises the following steps: , wherein, Is the firstThe fitting order of the non-intermittent directions,Is the firstDegree of dissimilarity in the non-intermittent direction,In order to preset the first value of the first value,In order to preset the second value of the first value,As an exponential function based on natural constants,In order to round, the preset first value is larger than the preset second value.
Correspondingly, for each discontinuous direction, fitting orders on the left side and the right side are calculated respectively, specifically: , wherein, Is the firstThe directions of the discontinuities correspond to the fitting orders on the left,Is the firstThe directions of the discontinuities correspond to the fitting orders on the right,Is the firstThe directions of the discontinuities correspond to the degree of dissimilarity on the left side,Is the firstThe directions of the discontinuities correspond to the degree of dissimilarity on the right,In order to preset the first value of the first value,In order to preset the second value of the first value,As an exponential function based on natural constants,In order to round, the preset first value is larger than the preset second value.
In this embodiment, the lowest order of the polynomial fitting function is set to be greater than 1 degree due to the non-linear variation trend of the glue coating thickness, but too high order also results in the over-fitting condition, so that the value range of the fitting order of the polynomial fitting function is set to be withinThus, the first value is presetThe value is 5, and the second value is presetTake a value of 2, as another embodiment, a first value is presetThe value is 4, and a second value is presetThe value is 3, and the implementer can set the value according to the actual situation.
The smaller the fitting order, the smaller the fluctuation state of the glue coating thickness is, and the larger the fitting order, the larger the fluctuation state of the glue coating thickness is.
Further, based on the fitting order, fitting film thicknesses of sampling points in different directions, specifically:
Based on the fitting order, performing polynomial curve fitting on film thicknesses of all sampling points in each uninterrupted direction to obtain fitting curves in each uninterrupted direction;
based on the fitting order of the left side, performing polynomial curve fitting on film thicknesses of all sampling points positioned on the left side of the dividing point in each discontinuous direction, and obtaining a fitting curve of the left side corresponding to each discontinuous direction;
Performing polynomial curve fitting on film thicknesses of all sampling points positioned on the right side of the dividing point in each discontinuous direction based on the fitting order on the right side, and obtaining a fitting curve corresponding to the right side in each discontinuous direction;
Selecting the minimum value of the minimum values of all the fitting curves to be marked as the global minimum value;
the uniformity of the silicon carbide wafer is calculated as: , wherein, For uniformity of the silicon carbide wafer,As a consequence of the global maximum,Is the global minimum.
The larger the difference between the global maximum and the global minimum, the more uneven the coating of the silicon carbide wafer is reflected.
If the uniformity is greater than a preset second threshold, the gluing of the silicon carbide wafer is uneven, otherwise, the gluing of the silicon carbide wafer is even;
It should be noted that, the value range of the preset second threshold value is between 3% and 5%, so in this embodiment, the preset second threshold value is 3%, and as other embodiments, the implementer can set the preset second threshold value according to the actual situation. Therefore, if the uniformity is smaller than or equal to the preset second threshold, the uniformity of the gluing of the silicon carbide wafer is higher, and the silicon carbide wafer can be etched.
And aligning the photoetching mask plate with the silicon carbide wafer with uniform glue coating, and then irradiating the silicon carbide wafer by ultraviolet light through the photoetching mask plate to change the characteristics of the photoresist irradiated on the silicon carbide wafer, wherein the photoresist in the development area can be eliminated. The region of the silicon carbide groove can be effectively determined through the developing machine, so that the etching of the groove region is more accurate.
After the exposure, the mask layer is etched using an etcher that uses a dry etching process, such as Reactive Ion Etching (RIE), and then the photoresist is removed by a photoresist stripper. The patterned mask layer is used as a mask, an Inductively Coupled Plasma (ICP) etching process is adopted to etch the silicon carbide substrate to form a target groove, rough or striped repair is carried out on the side wall of the groove through wet chemical treatment, damage caused in the etching process can be repaired through an annealing process (such as high-temperature hydrogen or argon annealing), and the surface quality and the electrical characteristics are improved. And finally, removing the patterned mask layer by adopting a wet process to complete the whole groove etching process. The reactive ion etching, the inductively coupled plasma, the annealing process, and the wet process are all known techniques, and are not described herein.
It should be understood that, although the steps in the flowchart of fig. 1 are shown in sequence as indicated by the arrows, the steps are not necessarily performed in sequence as indicated by the arrows. The steps are not strictly limited to the order of execution unless explicitly recited herein, and the steps may be executed in other orders. Moreover, at least some of the steps in fig. 1 may include multiple sub-steps or stages that are not necessarily performed at the same time, but may be performed at different times, nor do the order in which the sub-steps or stages are performed necessarily performed in sequence, but may be performed alternately or alternately with at least a portion of other steps or sub-steps of other steps.
The technical features of the above embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.
The above examples merely represent a few embodiments of the present application, which are described in more detail and are not to be construed as limiting the application. It should be noted that, for those skilled in the art, several variations and modifications can be made without departing from the spirit of the present application, and therefore, any simple modification, equivalent variation and modification of the above embodiments according to the technical substance of the present application fall within the protection scope of the technical solution of the present application.
Claims (8)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202510708892.9A CN120237037B (en) | 2025-05-29 | 2025-05-29 | Silicon carbide groove etching method of semiconductor device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202510708892.9A CN120237037B (en) | 2025-05-29 | 2025-05-29 | Silicon carbide groove etching method of semiconductor device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN120237037A CN120237037A (en) | 2025-07-01 |
| CN120237037B true CN120237037B (en) | 2025-09-05 |
Family
ID=96161387
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202510708892.9A Active CN120237037B (en) | 2025-05-29 | 2025-05-29 | Silicon carbide groove etching method of semiconductor device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN120237037B (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102136419A (en) * | 2010-01-27 | 2011-07-27 | 中芯国际集成电路制造(上海)有限公司 | Method for improving uniformity of sidewall angle |
| CN118571774A (en) * | 2024-08-02 | 2024-08-30 | 深圳市冠禹半导体有限公司 | Quick test method, equipment and system for MOSFET device |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6366861B1 (en) * | 1997-04-25 | 2002-04-02 | Applied Materials, Inc. | Method of determining a wafer characteristic using a film thickness monitor |
| US9039907B2 (en) * | 2011-07-20 | 2015-05-26 | Imec | Methods for improving integrated photonic device uniformity |
| CN114485522B (en) * | 2022-04-06 | 2022-08-23 | 天津中环领先材料技术有限公司 | Method for testing surface damage layer thickness of <100> crystal orientation silicon single crystal grinding sheet |
-
2025
- 2025-05-29 CN CN202510708892.9A patent/CN120237037B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102136419A (en) * | 2010-01-27 | 2011-07-27 | 中芯国际集成电路制造(上海)有限公司 | Method for improving uniformity of sidewall angle |
| CN118571774A (en) * | 2024-08-02 | 2024-08-30 | 深圳市冠禹半导体有限公司 | Quick test method, equipment and system for MOSFET device |
Also Published As
| Publication number | Publication date |
|---|---|
| CN120237037A (en) | 2025-07-01 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| TW200403785A (en) | Method for in-situ monitoring of patterned substrate processing using reflectometry | |
| US20030000922A1 (en) | Using scatterometry to develop real time etch image | |
| JPS58110678A (en) | Etching process | |
| KR20160132048A (en) | Charged particle beam device and inspection device | |
| US6268226B1 (en) | Reactive ion etch loading measurement technique | |
| WO2006054459A1 (en) | Exposure condition setting method, substrate processing device, and computer program | |
| CN100587934C (en) | System and method for improving optical critical dimension measurement accuracy | |
| JP2017212439A (en) | Imprint apparatus and imprint method for correcting distortion in imprint system | |
| US7235336B1 (en) | Method for determining photoresist thickness and structure formed using determined photoresist thickness | |
| CN101369551B (en) | Process control for improving wafer uniformity using combined or independent metrics | |
| US5684301A (en) | Monocrystalline test structures, and use for calibrating instruments | |
| US20080165367A1 (en) | Roughness evaluation method and system | |
| TWI744469B (en) | Facilitation of spin-coat planarization over feature topography during substrate fabrication | |
| CN120237037B (en) | Silicon carbide groove etching method of semiconductor device | |
| CN101241309A (en) | Method for calibrating sub-nanometer critical dimension by utilizing spacing offset | |
| US6649426B2 (en) | System and method for active control of spacer deposition | |
| US20070178610A1 (en) | Semiconductor Production Apparatus | |
| JP4480482B2 (en) | Plasma etching processing apparatus control method and trimming amount control system | |
| US7052575B1 (en) | System and method for active control of etch process | |
| CN208806227U (en) | Wafer position detection device and semiconductor processing equipment | |
| Wong et al. | Endpoint prediction for polysilicon plasma etch via optical emission interferometry | |
| CN114861440A (en) | Method for predicting etching opening area, etching mask thickness and etching depth model | |
| JPH08213369A (en) | Manufacture of semiconductor device | |
| US20060285113A1 (en) | Reticle alignment technique | |
| US5043236A (en) | Process for determining the focussing of a photolithographic apparatus |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |