Method and device for measuring thickness of silicon wafer

Abstract

The invention provides a method and device for measuring the thickness of a silicon wafer, and belongs to the technical field of semiconductor manufacturing. The method comprises the steps that material attributes of a silicon wafer are analyzed, a target attribute value is obtained, and the target attribute value is used for indicating component information of the silicon wafer; under the condition that the target attribute value is greater than or equal to a preset threshold value, measuring the silicon wafer through a capacitance measurer to obtain a first thickness corresponding to the silicon wafer; and under the condition that the target attribute value is smaller than a preset threshold value, measuring the silicon wafer through an infrared measurer to obtain a second thickness corresponding to the silicon wafer. According to the invention, the accuracy of measuring the thickness of the silicon wafer can be effectively improved.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing technology, and in particular to a method and device for measuring the thickness of a silicon wafer. Background Art

[0002] During the semiconductor manufacturing process, silicon wafer thickness measurements are often required at multiple stages to ensure a smooth production process. Conventional silicon wafer thickness measurements typically use a single method, failing to account for variations in wafer thickness across different stages. This results in poor wafer thickness measurement accuracy. Summary of the Invention

[0003] In order to solve the above technical problems, the present invention provides a method and device for measuring the thickness of a silicon wafer, which can effectively improve the accuracy of thickness measurement of a silicon wafer.

[0004] In order to achieve the above objectives, the technical solution adopted in the embodiment of the present invention is:

[0005] In a first aspect, the present invention provides a method for measuring the thickness of a silicon wafer, the method comprising:

[0006] Analyzing the material properties of the silicon wafer to obtain a target property value, wherein the target property value is used to indicate the content of impurities in the silicon wafer;

[0007] When the target attribute value is greater than or equal to a preset threshold, measuring the silicon wafer using a capacitance measuring device to obtain a first thickness corresponding to the silicon wafer;

[0008] When the target property value is less than a preset threshold, the silicon wafer is measured by an infrared measuring device to obtain a second thickness corresponding to the silicon wafer.

[0009] In some embodiments, the capacitance measuring device includes a first probe and a second probe arranged opposite to each other, and when the target property value is greater than or equal to a preset threshold, measuring the silicon wafer using the capacitance measuring device to obtain a first thickness corresponding to the silicon wafer includes:

[0010] When the target attribute value is greater than or equal to a preset threshold, the silicon wafer is placed between the first probe and the second probe for measurement to obtain a first measurement value and a second measurement value, respectively. The first measurement value is the distance between the first surface of the silicon wafer and the first probe, and the second measurement value is the distance between the second surface of the silicon wafer and the second probe. The first probe and the second probe are capacitive thickness measurement probes.

[0011] The first measurement value and the second measurement value are calculated to obtain a first thickness corresponding to the silicon wafer.

[0012] In some embodiments, the first probe includes a first capacitance sensor and a second capacitance sensor connected in parallel, and the second probe includes a third capacitance sensor and a fourth capacitance sensor connected in parallel;

[0013] Wherein, the first capacitance sensor, the second capacitance sensor, the third capacitance sensor and the fourth capacitance sensor all include a temperature compensation circuit;

[0014] The first capacitance sensor and the second capacitance sensor are used to measure the capacitance of the silicon wafer according to temperature compensation to obtain the first measurement value, and the third capacitance sensor and the fourth capacitance sensor are used to measure the capacitance of the silicon wafer according to temperature compensation to obtain the second measurement value.

[0015] In some embodiments, the measuring range of the first probe and the second probe is greater than or equal to 100 Ω·cm.

[0016] In some embodiments, the infrared measuring device includes an infrared probe for emitting infrared laser light and a receiver for receiving reflected laser light, the infrared probe and the receiver being disposed above the silicon wafer. When the target property value is less than a preset threshold, the infrared measuring device is used to measure the silicon wafer to obtain the corresponding second thickness of the silicon wafer, including:

[0017] When the target attribute value is greater than or equal to a preset threshold, the infrared probe emits the infrared laser to the first surface of the silicon wafer, and obtains a first reflected laser and a second reflected laser based on the receiver, where the first reflected laser is the laser reflected by the first surface of the silicon wafer, and the second reflected laser is the laser reflected by the second surface of the silicon wafer;

[0018] The first reflected laser light and the second reflected laser light are calculated to obtain a second thickness corresponding to the silicon wafer.

[0019] In some embodiments, the angle between the infrared laser and the first surface of the silicon wafer is in a range of 15 degrees to 30 degrees.

[0020] In some embodiments, the material properties of the silicon wafer include doping level and / or resistance data, where the doping level is used to indicate the content of impurities in the silicon wafer, and the resistance data is used to indicate the resistance value of the silicon wafer.

[0021] In a second aspect, the present invention provides a device for measuring the thickness of a silicon wafer, the device comprising:

[0022] an analysis module, configured to analyze material properties of the silicon wafer to obtain a target property value, wherein the target property value is used to indicate composition information of the silicon wafer;

[0023] a first measuring module, configured to measure the silicon wafer using a capacitance measuring device to obtain a first thickness corresponding to the silicon wafer when the target attribute value is greater than or equal to a preset threshold;

[0024] The second measurement module is configured to measure the silicon wafer using an infrared measuring device to obtain a second thickness corresponding to the silicon wafer when the target property value is less than a preset threshold.

[0025] In a third aspect, the present invention further provides an electronic device comprising a processor, a memory, and a computer program stored in the memory and executable on the processor, wherein the computer program, when executed by the processor, implements the steps of the method described in the first aspect above.

[0026] In a fourth aspect, the present invention further provides a computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the steps in the method described in the first aspect are implemented.

[0027] In a fifth aspect, the present invention further provides a computer program product comprising computer instructions, which, when executed by a processor, implement the steps of the method described in the first aspect above.

[0028] The beneficial effects of the present invention are:

[0029] In this embodiment, the material properties of a silicon wafer are analyzed to obtain a target property value, which indicates the composition information of the silicon wafer. When the target property value is greater than or equal to a preset threshold, the silicon wafer is measured using a capacitance meter to obtain a first thickness corresponding to the silicon wafer. When the target property value is less than the preset threshold, the silicon wafer is measured using an infrared meter to obtain a second thickness corresponding to the silicon wafer. The technical solution of the present invention allows the composition information of the silicon wafer to be analyzed before thickness measurement to obtain a target property value corresponding to the composition information. Based on the comparison of the target property value with the preset threshold, it is determined whether to use a capacitance meter or an infrared meter to measure the silicon wafer. This allows the selection of the appropriate thickness measurement method for silicon wafers with different property values, effectively improving the accuracy of thickness measurement of silicon wafers. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solution of the present invention, the following is a brief introduction to the drawings required for the description of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0031] Figure 1 This is a flow chart of a method for measuring the thickness of a silicon wafer provided in an embodiment of the present invention;

[0032] Figure 2 This is one of the structural diagrams of the capacitance measuring device in an embodiment of the present invention;

[0033] Figure 3 This is the second structural diagram of the capacitance measuring device in an embodiment of the present invention;

[0034] Figure 4 This is the third structural diagram of the capacitance measuring device according to the embodiment of the present invention;

[0035] Figure 5 1 is a measurement diagram of an infrared measuring device in an embodiment of the present invention.

[0036] Figure 6 Schematic diagram of the structure of the infrared measuring device and the capacitance measuring device in an embodiment of the present invention;

[0037] Figure 7 1 is a structural diagram of a silicon wafer thickness measuring device provided in an embodiment of the present invention;

[0038] Figure 8 It is a structural diagram of an electronic device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0039] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the described embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field are within the scope of protection of the present invention.

[0040] The present invention provides a method and device for measuring the thickness of a silicon wafer, which can effectively improve the accuracy of measuring the thickness of the silicon wafer.

[0041] The embodiment of the present invention provides a method for measuring the thickness of a silicon wafer, such as Figure 1 Shown, including:

[0042] Step 101: Analyze the material properties of the silicon wafer to obtain a target property value, where the target property value is used to indicate the content of impurities in the silicon wafer.

[0043] In this embodiment, in order to reduce the influence of temperature and silicon wafer doping on silicon wafer thickness measurement, before measuring the thickness of the silicon wafer, it is necessary to analyze the composition information of the silicon wafer to obtain a target attribute value, where the target attribute value is a representative value of the composition information in the silicon wafer.

[0044] In some embodiments, the material properties of the silicon wafer include doping level and / or resistance data, where the doping level is used to indicate the content of impurities in the silicon wafer, and the resistance data is used to indicate the resistance value of the silicon wafer.

[0045] Specifically, in this embodiment, the material properties of the silicon wafer include doping level and / or resistance data, wherein the doping level includes the content of impurities in the silicon wafer, and the resistance data includes the resistance value of the silicon wafer. By analyzing the doping level and / or resistance data, the corresponding composition information of the silicon wafer can be accurately determined, thereby facilitating the selection of an appropriate thickness measurement method to measure the silicon wafer.

[0046] It should be noted that capacitance measurement is not very effective for silicon wafers with low doping levels, while infrared measurement is ineffective for highly doped and rough-surfaced silicon wafers. Furthermore, capacitance measurement is less effective for measuring high resistance values. Therefore, before measuring the thickness of the silicon wafer in this embodiment, the material properties of the silicon wafer must be analyzed. Specifically, the properties of the silicon wafer can be analyzed using any of the following methods: resistivity measurement, Hall effect measurement, and thermal analysis, among others. The analysis method is not specifically limited in this embodiment.

[0047] Step 102: When the target attribute value is greater than or equal to a preset threshold, measure the silicon wafer using a capacitance measuring device to obtain a first thickness corresponding to the silicon wafer.

[0048] In this embodiment, since the capacitance meter and the infrared meter have different requirements for property values, the measurement effects of the capacitance meter and the infrared meter are comprehensively considered to determine a preset threshold. When the target property value is greater than or equal to the preset threshold, the effect of using the capacitance meter to detect the thickness of the silicon wafer is better. Therefore, the silicon wafer is measured by the capacitance meter to obtain the first thickness corresponding to the silicon wafer.

[0049] It's important to note that a capacitance meter is a device used to measure silicon wafer thickness using the capacitance thickness method. A capacitance meter is an instrument that uses the principle of capacitance to measure material thickness. The basic measurement principle is based on the relationship between changes in capacitance and material thickness, allowing the thickness of the silicon wafer to be calculated.

[0050] Step 103 : When the target attribute value is less than a preset threshold, the silicon wafer is measured by an infrared measuring device to obtain a second thickness corresponding to the silicon wafer.

[0051] In this embodiment, when the target attribute value is less than the preset threshold, the effect of using an infrared measuring device to detect the thickness of the silicon wafer is better. Therefore, the silicon wafer is measured by the infrared measuring device to obtain the second thickness corresponding to the silicon wafer. For example, the impurities in the silicon wafer may be phosphorus (P), boron (B) and oxygen (O). When the impurity is P, the preset threshold may be set to 10^13 to 10^16 atoms / cm 3 When the impurity is B, the preset threshold can be set to 10^13 to 10^16 atoms / cm 3 When the impurity is O, the preset threshold can be set to 10^17 to 10^18 atoms / cm 3 It should be noted that an infrared gauge is a device used to measure silicon wafer thickness using the infrared thickness measurement method. This method utilizes the principle of infrared radiation to measure material thickness. Its basic measurement principle relies on the absorption characteristics of infrared light and is suitable for non-contact measurement of the thickness of various materials, thereby determining the thickness of silicon wafers.

[0052] In this embodiment, the material properties of a silicon wafer are analyzed to obtain a target property value, which indicates the composition information of the silicon wafer. When the target property value is greater than or equal to a preset threshold, the silicon wafer is measured using a capacitance meter to obtain a first thickness corresponding to the silicon wafer. When the target property value is less than the preset threshold, the silicon wafer is measured using an infrared meter to obtain a second thickness corresponding to the silicon wafer. The technical solution of the present invention allows the composition information of the silicon wafer to be analyzed before thickness measurement to obtain a target property value corresponding to the composition information. Based on the comparison of the target property value with the preset threshold, it is determined whether to use a capacitance meter or an infrared meter to measure the silicon wafer. This allows the selection of the appropriate thickness measurement method for silicon wafers with different property values, effectively improving the accuracy of thickness measurement of silicon wafers.

[0053] In some embodiments, the capacitance measuring device includes a first probe and a second probe arranged opposite to each other, and when the target property value is greater than or equal to a preset threshold, measuring the silicon wafer using the capacitance measuring device to obtain a first thickness corresponding to the silicon wafer includes:

[0054] When the target attribute value is greater than or equal to a preset threshold, the silicon wafer is placed between the first probe and the second probe for measurement to obtain a first measurement value and a second measurement value, respectively. The first measurement value is the distance between the first surface of the silicon wafer and the first probe, and the second measurement value is the distance between the second surface of the silicon wafer and the second probe. The first probe and the second probe are capacitive thickness measurement probes.

[0055] The first measurement value and the second measurement value are calculated to obtain a first thickness corresponding to the silicon wafer.

[0056] In this embodiment, if Figure 2 As shown, Figure 2 This is a schematic diagram of a capacitance meter. The capacitance meter includes a first probe (probe A) and a second probe (probe B) positioned opposite each other. The capacitance meter measures distance by evaluating the capacitive reactance of a flat plate capacitor. The formula for capacitive reactance, Xc, is:

[0057]

[0058] Substituting the capacitance formula C = εA / d into the capacitive reactance formula, we get:

[0059] That is, Xc∝d

[0060] Using this principle, Probe A can measure the distance from the front of the wafer to the probe, while Probe B can measure the distance from the back of the wafer to the probe. (See A and B in the figure.) The distance between the upper and lower probes is determined during calibration, so the substrate thickness can be determined. Specifically, the first probe measures the distance between the first surface of the silicon wafer and the first probe to obtain a first measurement value, while the second probe measures the distance between the second surface of the silicon wafer and the second probe to obtain a second measurement value. The first thickness of the silicon wafer is then calculated based on the first and second measurement values.

[0061] In some embodiments, the first probe includes a first capacitance sensor and a second capacitance sensor connected in parallel, and the second probe includes a third capacitance sensor and a fourth capacitance sensor connected in parallel;

[0062] Wherein, the first capacitance sensor, the second capacitance sensor, the third capacitance sensor and the fourth capacitance sensor all include a temperature compensation circuit;

[0063] The first capacitance sensor and the second capacitance sensor are used to measure the capacitance of the silicon wafer according to temperature compensation to obtain the first measurement value, and the third capacitance sensor and the fourth capacitance sensor are used to measure the capacitance of the silicon wafer according to temperature compensation to obtain the second measurement value.

[0064] In this embodiment, temperature affects the capacitance measurement device, specifically the dielectric constant of the medium. The dielectric constant of many materials changes with temperature. For example, in ceramic materials, as temperature rises, the internal crystal structure may undergo slight changes, resulting in a decrease in the dielectric constant. For a parallel plate capacitor, the capacitance value C = εS / d (where ε is the dielectric constant, S is the plate area, and d is the plate spacing, i.e., the thickness being measured). When the dielectric constant ε changes with temperature, the capacitance value will change accordingly, assuming other conditions remain unchanged. In some polymer materials, the movement of the molecular chains intensifies as temperature rises, causing the dielectric constant to decrease. If the temperature-induced dielectric constant change is not taken into account when measuring the thickness of a film made of such materials using the capacitance method, measurement errors will result. Plate expansion and contraction: Temperature changes can cause the physical dimensions of the capacitor plates to change. Generally speaking, objects expand when heated and contract when cooled. If the plates are made of metal, they will expand when the temperature rises. Assuming the plate spacing is d, d will decrease as the plates expand. According to the capacitance formula C=εS / d, when the dielectric constant ε and the plate area S remain unchanged, the capacitance value C will increase. This change in capacitance due to changes in the plate size will interfere with the accurate measurement of thickness. Impact on accuracy: increased nonlinear error (the combined effect of the above factors caused by temperature is often not a simple linear relationship. For example, in the measurement of a composite structure, the responses of different material layers to temperature are not synchronized. One layer of material has a larger thermal expansion coefficient and the other layer has a smaller one. This will cause the relationship between capacitance and thickness to deviate from the ideal linear model during temperature changes, thereby increasing the nonlinear error of the measurement.) and reduced stability (as the temperature fluctuates, the capacitance value continues to change, making the stability of the measurement system worse. If the ambient temperature is difficult to accurately control during the industrial production process, then the equipment for thickness measurement by capacitance method needs to be calibrated frequently, otherwise the reliability of the measurement results will be greatly reduced).

[0065] Therefore, it is necessary to improve the capacitance measurement method, such as Figure 3 As shown, Figure 3 This is the second structural diagram of a capacitance measuring device. Two capacitance sensors are installed in the first and second probes, respectively. Each capacitance sensor includes a temperature compensation circuit that compensates for the sensor's temperature based on the temperature, ensuring a stable temperature environment. A constant temperature control device, such as a sealed box, can also be installed to protect the sensors and keep them within a suitable temperature range.

[0066] Thus, the thickness of the silicon wafer can be determined by Figure 3 Calculated in this way, T w =G total-(A+B).

[0067] Among them, T w is the thickness of the silicon wafer, G total The total distance between the first probe and the second probe arranged opposite to each other is: A is the distance between the first probe and the first surface of the silicon wafer; B is the distance between the second probe and the second surface of the silicon wafer.

[0068] In some embodiments, the measuring range of the first probe and the second probe is greater than or equal to 100 Ω·cm.

[0069] In this embodiment, if Figure 4 As shown, Figure 4 This is the third structural diagram of a capacitance meter. The measurement range of the first and second probes can be expanded. Specifically, in the prior art, the measurement range of the probes is generally 1 Ω·cm to 100 Ω·cm. In this application, however, the measurement range can be set to 100 Ω·cm or above, for example, 150 Ω·cm or 180 Ω·cm. This increased range reduces the impact of temperature on the probes.

[0070] In some embodiments, the infrared measuring device includes an infrared probe for emitting infrared laser light and a receiver for receiving reflected laser light, the infrared probe and the receiver being disposed above the silicon wafer. When the target property value is less than a preset threshold, the infrared measuring device is used to measure the silicon wafer to obtain the corresponding second thickness of the silicon wafer, including:

[0071] When the target attribute value is greater than or equal to a preset threshold, the infrared probe emits the infrared laser to the first surface of the silicon wafer, and obtains a first reflected laser and a second reflected laser through the receiver, where the first reflected laser is the laser reflected by the first surface of the silicon wafer, and the second reflected laser is the laser reflected by the second surface of the silicon wafer;

[0072] The first reflected laser light and the second reflected laser light are calculated to obtain a second thickness corresponding to the silicon wafer.

[0073] In this embodiment, the infrared measuring device can be an infrared laser thickness gauge. As a non-contact measuring instrument, the infrared laser thickness gauge is very suitable for silicon wafer thickness testing due to its high precision and high efficiency. It emits infrared laser to the surface of the object. The same light source will emit when passing through the upper and lower surfaces. When two beams of light with the same properties have an optical path difference and are superimposed, interference will occur, and a spectrum containing layer thickness information can be obtained. By calculating the Fourier transform of the reflection spectrum, the FT spectrum can be obtained. For example, the thickness corresponding to the highest peak is the substrate thickness, such as Figure 5 As shown, Figure 5 Schematic diagram of the measurement of the infrared measuring device in this embodiment.

[0074] Specifically, the infrared measuring instrument includes an infrared probe for emitting infrared laser and a receiver for receiving reflected laser. Figure 6 As shown, Figure 6 This is a schematic diagram of the infrared measuring device and capacitance measuring device in this embodiment. The infrared probe and receiver are positioned above the silicon wafer. When the target property value is less than a preset threshold, the infrared measuring device measures the silicon wafer to obtain the corresponding second thickness. When the target property value is greater than or equal to the preset threshold, the capacitance measuring device measures the silicon wafer to obtain the corresponding first thickness. This allows for the ability to switch thickness measurement modes based on demand, effectively minimizing the impact of temperature on capacitance measurement and enabling testing of silicon wafers of various doping types.

[0075] In some embodiments, the angle between the infrared laser and the first surface of the silicon wafer is in a range of 15 degrees to 30 degrees.

[0076] In this embodiment, the angle between the infrared laser and the first surface of the silicon wafer is in the range of 15 degrees to 30 degrees, while in the prior art, during the measurement process, the angle between the infrared laser and the silicon wafer is 90 degrees. The setting method in this application can effectively avoid the problem of poor surface flatness of the silicon wafer.

[0077] Specifically, setting the angle between the infrared laser and the first surface of the silicon wafer within a range of 15 to 30 degrees helps reduce reflection losses of the laser beam at the interface while increasing the coherence of the transmitted light within the silicon wafer. This also increases the optical path length of the light within the silicon wafer, making the phase difference between the transmitted and reflected light more pronounced, facilitating the formation of measurable interference fringes, resulting in better measurement results.

[0078] Through the technical solution of the present invention, before measuring the thickness of the silicon wafer, the component information in the silicon wafer can be analyzed to obtain the target attribute value corresponding to the component information in the silicon wafer. Then, based on the comparison between the target attribute value and the preset threshold, it is determined whether to use a capacitance measuring device or an infrared measuring device to measure the silicon wafer. This realizes the selection of the appropriate thickness measurement method for silicon wafers with different attribute values, and effectively improves the accuracy of the thickness measurement of the silicon wafer.

[0079] The embodiment of the present invention also provides a device for measuring the thickness of a silicon wafer, such as Figure 7 Shown, including:

[0080] An analysis module 710 is configured to analyze material properties of the silicon wafer to obtain a target property value, wherein the target property value is used to indicate composition information of the silicon wafer;

[0081] A first measurement module 720 is configured to measure the silicon wafer using a capacitance measuring device to obtain a first thickness corresponding to the silicon wafer when the target attribute value is greater than or equal to a preset threshold;

[0082] The second measurement module 730 is configured to measure the silicon wafer using an infrared measuring device to obtain a second thickness corresponding to the silicon wafer when the target property value is less than a preset threshold.

[0083] In some embodiments, the capacitance measurer includes a first probe and a second probe disposed opposite to each other, and the first measurement module 720 includes:

[0084] a measurement submodule, configured to, when the target attribute value is greater than or equal to a preset threshold, place the silicon wafer between the first probe and the second probe for measurement, to obtain a first measurement value and a second measurement value, respectively, wherein the first measurement value is the distance between the first surface of the silicon wafer and the first probe, and the second measurement value is the distance between the second surface of the silicon wafer and the second probe, and the first probe and the second probe are capacitive thickness measurement probes;

[0085] The first calculation submodule is configured to calculate the first measurement value and the second measurement value to obtain a first thickness corresponding to the silicon wafer.

[0086] In some embodiments, the first probe includes a first capacitance sensor and a second capacitance sensor connected in parallel, and the second probe includes a third capacitance sensor and a fourth capacitance sensor connected in parallel;

[0087] Wherein, the first capacitance sensor, the second capacitance sensor, the third capacitance sensor and the fourth capacitance sensor all include a temperature compensation circuit;

[0088] The first capacitance sensor and the second capacitance sensor are used to measure the capacitance of the silicon wafer according to temperature compensation to obtain the first measurement value, and the third capacitance sensor and the fourth capacitance sensor are used to measure the capacitance of the silicon wafer according to temperature compensation to obtain the second measurement value.

[0089] In some embodiments, the measuring range of the first probe and the second probe is greater than or equal to 100Ω / mm.

[0090] In some embodiments, the infrared measuring device includes an infrared probe for emitting infrared laser and a receiver for receiving reflected laser, and the second measuring module 730 includes:

[0091] a receiving submodule, configured to, when the target attribute value is greater than or equal to a preset threshold, cause the infrared probe to emit the infrared laser light toward the first surface of the silicon wafer, and obtain, based on the receiver, a first reflected laser light and a second reflected laser light, wherein the first reflected laser light is the laser light reflected from the first surface of the silicon wafer, and the second reflected laser light is the laser light reflected from the second surface of the silicon wafer;

[0092] The second calculation submodule is configured to calculate the first reflected laser light and the second reflected laser light to obtain a second thickness corresponding to the silicon wafer.

[0093] In some embodiments, the angle between the infrared laser and the first surface of the silicon wafer is in a range of 15 degrees to 30 degrees.

[0094] Through the technical solution of the present invention, before measuring the thickness of the silicon wafer, the component information in the silicon wafer can be analyzed to obtain the target attribute value corresponding to the component information in the silicon wafer. Then, based on the comparison between the target attribute value and the preset threshold, it is determined whether to use a capacitance measuring device or an infrared measuring device to measure the silicon wafer. This realizes the selection of the appropriate thickness measurement method for silicon wafers with different attribute values, and effectively improves the accuracy of the thickness measurement of the silicon wafer.

[0095] The embodiment of the present invention also provides an electronic device. Figure 8 , the electronic device may include a processor 801, a memory 802, and a program 8021 stored in the memory 802 and executable on the processor 801.

[0096] When the program 8021 is executed by the processor 801, it can achieve Figure 1 Any steps in the corresponding method embodiments can achieve the same technical effects and will not be described again here to avoid repetition.

[0097] An embodiment of the present invention further provides a computer-readable storage medium storing a computer program. When executed by a processor, the computer program implements the various steps of the aforementioned silicon wafer thickness measurement method embodiment and achieves the same technical effects. To avoid repetition, the details are not described here. The computer-readable storage medium may be, for example, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0098] An embodiment of the present invention further provides a computer program product, which is stored in a storage medium. The computer program product is executed by at least one processor to implement the various processes of the above-mentioned silicon wafer thickness measurement method embodiment and can achieve the same technical effect. To avoid repetition, it will not be described here.

[0099] It should be noted that, in this document, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or apparatus comprising the element.

[0100] Through the description of the above embodiments, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus the necessary general hardware platform, and of course can also be implemented by hardware, but in many cases the former is a better embodiment. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk), and includes a number of instructions for enabling a terminal (which can be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in each embodiment of the present invention.

[0101] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the present invention and the claims, all of which are protected by the present invention.

[0102] Through the description of the above embodiments, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus the necessary general hardware platform, and of course can also be implemented by hardware, but in many cases the former is a better embodiment. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk), and includes a number of instructions for enabling a terminal (which can be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in each embodiment of the present invention.

[0103] In the various method embodiments of the present disclosure, the serial numbers of the steps cannot be used to limit the order of the steps. For ordinary technicians in this field, without paying any creative work, changes to the order of the steps are also within the scope of protection of the present disclosure.

[0104] It should be noted that the various embodiments in this specification are described in a progressive manner. Similar parts between the various embodiments can be referred to in conjunction with each other. Each embodiment focuses on the differences from other embodiments. In particular, since the embodiments are generally similar to the product embodiments, the description is relatively simple. For relevant parts, refer to the partial description of the product embodiments.

[0105] The above is a preferred embodiment of the present disclosure. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles described in the present disclosure. These improvements and modifications should also be regarded as the scope of protection of the present disclosure.

Claims

1. A method for measuring the thickness of a silicon wafer, characterized in that: The method comprises: Analyzing the material properties of the silicon wafer to obtain a target property value, wherein the target property value is used to indicate the composition information of the silicon wafer; When the target attribute value is greater than or equal to a preset threshold, measuring the silicon wafer using a capacitance measuring device to obtain a first thickness corresponding to the silicon wafer; When the target property value is less than a preset threshold, the silicon wafer is measured by an infrared measuring device to obtain a second thickness corresponding to the silicon wafer.

2. The method according to claim 1, characterized in that The capacitance measuring device includes a first probe and a second probe arranged opposite to each other. When the target attribute value is greater than or equal to a preset threshold, the capacitance measuring device measures the silicon wafer to obtain a first thickness corresponding to the silicon wafer, including: When the target attribute value is greater than or equal to a preset threshold, the silicon wafer is placed between the first probe and the second probe for measurement to obtain a first measurement value and a second measurement value, respectively. The first measurement value is the distance between the first surface of the silicon wafer and the first probe, and the second measurement value is the distance between the second surface of the silicon wafer and the second probe. The first probe and the second probe are capacitive thickness measurement probes. The first measurement value and the second measurement value are calculated to obtain a first thickness corresponding to the silicon wafer.

3. The method according to claim 2, characterized in that The first probe includes a first capacitance sensor and a second capacitance sensor connected in parallel, and the second probe includes a third capacitance sensor and a fourth capacitance sensor connected in parallel; Wherein, the first capacitance sensor, the second capacitance sensor, the third capacitance sensor and the fourth capacitance sensor all include a temperature compensation circuit; The first capacitance sensor and the second capacitance sensor are used to measure the capacitance of the silicon wafer according to temperature compensation to obtain the first measurement value, and the third capacitance sensor and the fourth capacitance sensor are used to measure the capacitance of the silicon wafer according to temperature compensation to obtain the second measurement value.

4. The method according to any one of claims 2 or 3, characterized in that The measuring range of the first probe and the second probe is greater than or equal to 100Ω·cm.

5. The method according to claim 1, wherein The infrared measuring device includes an infrared probe for emitting infrared laser light and a receiver for receiving reflected laser light, wherein the infrared probe and the receiver are disposed above the silicon wafer. When the target attribute value is less than a preset threshold, the infrared measuring device measures the silicon wafer to obtain a second thickness corresponding to the silicon wafer, including: When the target attribute value is greater than or equal to a preset threshold, the infrared probe emits the infrared laser to the first surface of the silicon wafer, and obtains a first reflected laser and a second reflected laser based on the receiver, where the first reflected laser is the laser reflected by the first surface of the silicon wafer, and the second reflected laser is the laser reflected by the second surface of the silicon wafer; The first reflected laser light and the second reflected laser light are calculated to obtain a second thickness corresponding to the silicon wafer.

6. The method according to claim 5, characterized in that The included angle between the infrared laser and the first surface of the silicon wafer is in the range of 15 degrees to 30 degrees.

7. The method according to claim 1, characterized in that The material properties of the silicon wafer include doping level and / or resistance data, wherein the doping level is used to indicate the content of impurities in the silicon wafer, and the resistance data is used to indicate the resistance value of the silicon wafer.

8. A device for measuring the thickness of a silicon wafer, characterized in that: The device comprises: an analysis module, configured to analyze material properties of the silicon wafer to obtain a target property value, wherein the target property value is used to indicate composition information of the silicon wafer; a first measuring module, configured to measure the silicon wafer using a capacitance measuring device to obtain a first thickness corresponding to the silicon wafer when the target attribute value is greater than or equal to a preset threshold; The second measurement module is configured to measure the silicon wafer using an infrared measuring device to obtain a second thickness corresponding to the silicon wafer when the target property value is less than a preset threshold.

9. An electronic device, characterized in that: include: A processor, a memory, and a program stored in the memory and executable on the processor, wherein the program, when executed by the processor, implements the steps of the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, which implements the steps of the method according to any one of claims 1 to 7 when executed by a processor.

11. A computer program product, characterized in that The method comprises computer instructions, which, when executed by a processor, implement the steps of the method according to any one of claims 1 to 7.

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