Silicon carbide wafer thickness measurement control device and measurement method

Abstract

The invention belongs to the field of measurement technology, specifically relates to thickness measurement, and in particular to a silicon carbide wafer thickness measurement control device and a measurement method, comprising: a cover plate, a support plate and a detection mechanism; the cover plate is located above the support plate; at least one bearing mechanism is arranged on the top surface of the support plate, and the bearing mechanism is suitable for bearing the silicon carbide wafer; the detection mechanism comprises: a first distance measuring module and a second distance measuring module arranged on the bottom surface of the cover plate; the control module is configured to obtain the thickness of the silicon carbide wafer according to the distance between the first distance measuring module and the silicon carbide wafer with a surface covered with diamond liquid and the distance between the second distance measuring module and the bearing mechanism with a surface covered with diamond liquid during the grinding process, thereby realizing accurate detection of the thickness of the silicon carbide wafer during the grinding process, and avoiding the silicon carbide wafer being scrapped due to grinding too thin.

Description

Technical Field

[0001] The present invention belongs to the field of measurement technology, and specifically relates to thickness measurement, and in particular to a silicon carbide wafer thickness measurement control device and a measurement method. Background Art

[0002] Silicon carbide wafers need to be ground during the production process so that the thickness of the silicon carbide wafers meets the requirements. When grinding silicon carbide wafers, the relevant technology uses manual estimation of the grinding removal amount to calculate the thickness of the silicon carbide wafer, which will lead to inaccurate thickness calculation, resulting in the silicon carbide wafer being too thin and being scrapped or requiring rework.

[0003] Therefore, due to the technical problem that the thickness of the silicon carbide wafer cannot be accurately detected during the grinding process, it is necessary to design a new silicon carbide wafer thickness measurement control device and measurement method.

[0004] It should be noted that the above information disclosed in this background technology section is only used to understand the background technology of the present application concept, and therefore, the above description is not considered to constitute information of the prior art. Summary of the invention

[0005] The embodiments of the present disclosure at least provide a silicon carbide wafer thickness measurement control device and a measurement method.

[0006] In a first aspect, an embodiment of the present disclosure provides a silicon carbide wafer thickness measurement control device, comprising:

[0007] Cover plate, support plate and detection mechanism;

[0008] The cover plate is located above the support plate;

[0009] At least one bearing mechanism is disposed on the top surface of the support plate, and the bearing mechanism is suitable for bearing the silicon carbide wafer;

[0010] The detection mechanism comprises: a first distance measuring module and a second distance measuring module arranged on the bottom surface of the cover plate;

[0011] The first distance measuring module and the second distance measuring module are both electrically connected to the control module;

[0012] The first distance measuring module is arranged closer to the center of the cover plate than the second distance measuring module;

[0013] The first distance measuring module is suitable for detecting the distance between the first distance measuring module and the silicon carbide wafer whose surface is covered with diamond liquid;

[0014] The second distance measuring module is suitable for detecting the distance between the second distance measuring module and the supporting mechanism whose surface is covered with diamond liquid;

[0015] The control module is configured to obtain the thickness of the silicon carbide wafer according to the distance between the first distance measuring module and the silicon carbide wafer with the surface covered with diamond liquid and the distance between the second distance measuring module and the supporting mechanism with the surface covered with diamond liquid during the grinding process.

[0016] In an optional embodiment, the control module is configured to obtain the thickness of the silicon carbide wafer according to the distance between the first distance measuring module and the silicon carbide wafer with the surface covered with diamond liquid and the distance between the second distance measuring module and the supporting mechanism with the surface covered with diamond liquid during the grinding process, that is,

[0017] The thickness of the silicon carbide wafer = (the distance between the second distance measuring module and the supporting mechanism with the surface covered with diamond liquid - the distance between the first distance measuring module and the silicon carbide wafer with the surface covered with diamond liquid) + the thickness of the supporting mechanism;

[0018] Wherein, the thickness of the bearing mechanism is preset in the control module;

[0019] The cover plate is connected to a first driving mechanism, the first driving mechanism is suitable for driving the cover plate to rise and fall and rotate, and the first driving mechanism is connected to a control module;

[0020] When the thickness of the silicon carbide wafer reaches a preset standard value, the control module controls the first driving mechanism to stop.

[0021] In an optional embodiment, the bearing mechanism includes: a planetary wheel;

[0022] The support plate is circular, and a driving gear is arranged on the top surface thereof, and the driving gear is arranged concentrically with the support plate;

[0023] After the cover plate descends, the driving gear is connected to the cover plate, and the first driving mechanism rotates along with the cover plate;

[0024] A gear ring is arranged on the top surface of the support plate;

[0025] The planetary wheel is arranged on the top surface of the support plate, and the planetary wheel is located between the driving gear and the gear ring;

[0026] The planetary wheel is meshed with the driving gear, and the planetary wheel is meshed with the gear ring;

[0027] The planetary wheel is provided with a plurality of through holes, in which silicon carbide wafers are placed;

[0028] The thickness of the planetary wheel is smaller than the thickness of the gear ring, and the silicon carbide wafer is higher than the top surface of the gear ring;

[0029] The distance between the second distance measuring module and the supporting mechanism whose surface is covered with diamond liquid is the distance between the second distance measuring module and the planetary wheel whose surface is covered with diamond liquid.

[0030] In an optional embodiment, the silicon carbide wafer thickness measurement and control device further includes: a liquid spraying mechanism;

[0031] The liquid spraying mechanism passes through the cover plate;

[0032] The liquid outlet at the bottom of the liquid spraying mechanism is located above the driving gear;

[0033] The liquid spraying mechanism is suitable for disposing diamond liquid, and then the diamond liquid is sprayed between the cover plate and the supporting plate.

[0034] In an optional embodiment, the liquid spraying mechanism includes: a configuration box, a connecting pipe and a sleeve;

[0035] The bottom surface of the sleeve is sealed, and the top surface is open;

[0036] The configuration box is arranged above the cover plate;

[0037] The connecting pipe is vertically arranged, and the top end of the connecting pipe is connected with the bottom surface of the configuration box;

[0038] The bottom of the connecting pipe is inserted into the sleeve;

[0039] The sleeve passes through the driving gear, and the driving gear is rotatably connected to the outer wall of the sleeve;

[0040] The side wall of the sleeve is provided with a plurality of liquid outlets at equal intervals in the circumferential direction;

[0041] The lowest point of the connecting pipe is higher than the liquid outlet;

[0042] The liquid outlet is higher than the top surface of the driving gear;

[0043] The configuration box is provided with a concentration sensor electrically connected to the control module, and the concentration sensor is suitable for detecting the concentration of the diamond liquid in the configuration box;

[0044] The diamond liquid in the configuration box enters the sleeve through the connecting pipe, and then is sprayed between the cover plate and the support plate through the liquid outlet.

[0045] In an optional embodiment, a second driving mechanism is connected to the connecting pipe, and the second driving mechanism is electrically connected to the control module;

[0046] The second driving mechanism is suitable for driving the connecting pipe to rise and fall, so as to adjust the length of the connecting pipe extending into the configuration box and the length of the connecting pipe extending into the sleeve;

[0047] A first liquid inlet pipe, a second liquid inlet pipe and a feed pipe are arranged on the top surface of the configuration box;

[0048] The first liquid inlet pipe, the second liquid inlet pipe and the feed pipe are all connected to the interior of the configuration box;

[0049] The second liquid inlet pipe is located above the connecting pipe;

[0050] Grinding liquid is input into the configuration box through the first liquid inlet pipe, and corundum is input into the configuration box through the feed pipe to prepare diamond liquid in the configuration box. The diamond liquid enters the sleeve through the connecting pipe and is then sprayed between the cover plate and the support plate through the liquid outlet to grind the silicon carbide wafer.

[0051] In an optional embodiment, the control module is configured to control the second driving mechanism to drive the connecting pipe to rise according to the grinding speed of the silicon carbide wafer, that is,

[0052] The control module makes a judgment based on the speed of change of the thickness of the silicon carbide wafer. When the thickness of the silicon carbide wafer exceeds the preset change speed, it is judged that the silicon carbide wafer is ground too fast and the concentration of diamond sand in the diamond liquid is too high. At this time, the control module controls the solenoid valve in the connecting pipe to close, and then controls the second driving mechanism to drive the connecting pipe to rise so that the top of the connecting pipe contacts the second liquid inlet pipe, opens the solenoid valve, and inputs grinding liquid into the connecting pipe through the second liquid inlet pipe to reduce the concentration of the diamond liquid in the connecting pipe.

[0053] In an optional embodiment, when the control module determines that the silicon carbide wafer is ground too fast, after the top of the connecting pipe contacts the second liquid inlet pipe, the control module controls the water pump to extract the diamond liquid in the configuration box, and the water pump is connected to the inside of the configuration box through a pipeline;

[0054] After the diamond liquid in the configuration box is extracted, the control module obtains the residual amount of diamond sand in the configuration box;

[0055] T=T1+T2+T3;

[0056] T1=C1×ρ×A1;

[0057] T2 = C2 × ρ × A2;

[0058] T3 = C3 × ρ × A3;

[0059] Among them, T is the total amount of corundum residue; ρ is the density of corundum; T1 is the amount of corundum residue on the bottom surface of the configuration box; C1 is the deposition coefficient of the bottom surface of the configuration box; A1 is the area of ​​the bottom surface of the configuration box; T2 is the amount of corundum residue on the inner wall of the configuration box; C2 is the deposition coefficient of the inner wall of the configuration box; A2 is the area of ​​the inner wall of the configuration box; T3 is the amount of corundum residue on the top surface of the configuration box; C3 is the deposition coefficient of the top surface of the configuration box; A3 is the area of ​​the top surface of the configuration box.

[0060] In an optional embodiment, after obtaining the residual amount of corundum, the control module configures diamond liquid in the configuration box according to the residual amount of corundum and the preset concentration of diamond liquid. At this time, polishing liquid is input into the configuration box through the first liquid inlet pipe, and corundum is input into the configuration box through the feed pipe.

[0061] In a second aspect, the present disclosure also provides a measurement method using the above-mentioned silicon carbide wafer thickness measurement control device, comprising:

[0062] The first distance measuring module is suitable for detecting the distance between the first distance measuring module and the silicon carbide wafer whose surface is covered with diamond liquid;

[0063] The second distance measuring module is suitable for detecting the distance between the second distance measuring module and the supporting mechanism whose surface is covered with diamond liquid;

[0064] The control module is configured to obtain the thickness of the silicon carbide wafer according to the distance between the first distance measuring module and the silicon carbide wafer with the surface covered with diamond liquid and the distance between the second distance measuring module and the supporting mechanism with the surface covered with diamond liquid during the grinding process.

[0065] The invention has the beneficial effect that the silicon carbide wafer thickness measurement control device comprises: a cover plate, a support plate and a detection mechanism; the cover plate is located above the support plate; at least one bearing mechanism is arranged on the top surface of the support plate, and the bearing mechanism is suitable for bearing the silicon carbide wafer; the detection mechanism comprises: a first distance measuring module and a second distance measuring module arranged on the bottom surface of the cover plate; the first distance measuring module and the second distance measuring module are both electrically connected to the control module; the first distance measuring module is arranged closer to the center of the cover plate than the second distance measuring module; the first distance measuring module is suitable for detecting the distance between the first distance measuring module and the silicon carbide wafer with the surface covered with diamond liquid; the second distance measuring module is suitable for detecting the distance between the first distance measuring module and the silicon carbide wafer with the surface covered with diamond liquid and the distance between the second distance measuring module and the bearing mechanism with the surface covered with diamond liquid during the grinding process, thereby realizing the accurate detection of the thickness of the silicon carbide wafer during the grinding process, avoiding the silicon carbide wafer from being scrapped due to grinding too thin, and avoiding the silicon carbide wafer from being too thick and requiring rework.

[0066] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention are realized and obtained by the structures particularly pointed out in the description, claims and drawings.

[0067] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, this article specifically cites preferred embodiments and provides detailed descriptions as follows in conjunction with the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0068] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0069] Figure 1 A schematic diagram of the structure of a silicon carbide wafer thickness measurement control device provided in an embodiment of the present disclosure;

[0070] Figure 2 A schematic diagram of the internal structure of a silicon carbide wafer thickness measurement control device provided in an embodiment of the present disclosure;

[0071] Figure 3 A cross-sectional view of a silicon carbide wafer thickness measurement control device provided in an embodiment of the present disclosure;

[0072] Figure 4 A detection schematic diagram of a detection mechanism provided in an embodiment of the present disclosure;

[0073] Figure 5 A principle block diagram of a silicon carbide wafer thickness measurement control device provided in an embodiment of the present disclosure.

[0074] In the figure:

[0075] 1 cover plate, 11 first driving mechanism;

[0076] 2 support plate, 21 driving gear, 22 gear ring;

[0077] 3 detection mechanism, 31 first distance measuring module, 32 second distance measuring module;

[0078] 4 bearing mechanism, 41 planetary wheel, 42 through hole;

[0079] 5 liquid spraying mechanism, 51 configuration box, 52 connecting pipe, 53 sleeve, 54 liquid outlet, 55 first liquid inlet pipe, 56 second liquid inlet pipe, 57 feed pipe, 58 solenoid valve;

[0080] 6 Silicon carbide wafers. DETAILED DESCRIPTION

[0081] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0082] In this article, when it is mentioned that the first component is located on the second component, this may mean that the first component may be directly formed on the second component, or the third component may be interposed between the first component and the second component. In addition, in the drawings, in order to effectively describe the technical content, the thickness of the components may be exaggerated or reduced.

[0083] As used herein, the phrases "in one embodiment," "according to one embodiment," "in some embodiments," and the like generally refer to the fact that the particular feature, structure, or characteristic following the phrase may be included in at least one embodiment of the present disclosure. Therefore, a particular feature, structure, or characteristic may be included in more than one embodiment of the present disclosure, so that these phrases do not necessarily refer to the same embodiment. As used herein, the terms "example," "exemplary," and the like are used to "serve as an example, instance, or illustration." Any implementation, aspect, or design described herein as "example" or "exemplary" is not necessarily to be construed as preferred or superior to other implementations, aspects, or designs. On the contrary, the use of the terms "example," "exemplary," and the like is intended to present concepts in a concrete manner.

[0084] Some embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0085] like Figure 1 , Figure 4 and Figure 5 As shown, at least one disclosed embodiment provides a silicon carbide wafer thickness measurement control device, comprising: a cover plate 1, a support plate 2 and a detection mechanism 3; the cover plate 1 is located above the support plate 2; the bottom surface of the cover plate 1 and the top surface of the support plate 2 are both grinding surfaces, so as to grind both the top and bottom surfaces of the silicon carbide wafer 6; at least one supporting mechanism 4 is arranged on the top surface of the support plate 2, and the supporting mechanism 4 is suitable for carrying the silicon carbide wafer 6; the detection mechanism 3 comprises: a first distance measuring module 31 and a second distance measuring module 32 arranged on the bottom surface of the cover plate 1; the first distance measuring module 31 and the second distance measuring module 32 are both electrically connected to the control module; the first distance measuring module 31 is arranged closer to the center of the cover plate 1 than the second distance measuring module 32; the first distance measuring module 31 is suitable for detecting the distance between it and the silicon carbide wafer 6 whose surface is covered with diamond liquid, that is, Figure 4 h1; the second distance measuring module 32 is suitable for detecting the distance between the surface of the carrier mechanism 4 covered with diamond liquid, ie Figure 4h2; The control module is configured to obtain the thickness of the silicon carbide wafer 6 according to the distance between the first distance measuring module 31 and the silicon carbide wafer 6 with the surface covered with diamond liquid and the distance between the second distance measuring module 32 and the supporting mechanism 4 with the surface covered with diamond liquid during the grinding process, thereby realizing the accurate detection of the thickness of the silicon carbide wafer 6 during the grinding process, avoiding the silicon carbide wafer 6 being scrapped due to grinding too thin, and avoiding the silicon carbide wafer 6 being too thick and requiring rework. The distance measuring module can be, but is not limited to, a laser interferometer.

[0086] In an optional embodiment, the control module is configured to obtain the thickness of the silicon carbide wafer 6 according to the distance between the first distance measuring module 31 and the silicon carbide wafer 6 with the surface covered with diamond liquid and the distance between the second distance measuring module 32 and the supporting mechanism 4 with the surface covered with diamond liquid during the grinding process, that is,

[0087] The thickness of the silicon carbide wafer = (the distance between the second distance measuring module 32 and the supporting mechanism 4 whose surface is covered with diamond liquid - the distance between the first distance measuring module 31 and the silicon carbide wafer 6 whose surface is covered with diamond liquid) + the thickness of the supporting mechanism 4;

[0088] Among them, the thickness of the supporting mechanism 4 is preset in the control module; the cover plate 1 is connected to a first driving mechanism 11, the first driving mechanism 11 is suitable for driving the cover plate 1 to rise and fall and rotate, and the first driving mechanism 11 is connected to the control module; when the thickness of the silicon carbide wafer 6 reaches the preset standard value, the control module controls the first driving mechanism 11 to stop; during the grinding process of the silicon carbide wafer 6, its thickness is detected in real time to ensure that the thickness of the silicon carbide wafer 6 can accurately reach the standard value after grinding, to ensure the quality of the silicon carbide wafer 6, to avoid the silicon carbide wafer 6 being scrapped due to being too thin, and to avoid the silicon carbide wafer 6 being unable to be ground to the preset thickness, to ensure the efficiency and effect of grinding.

[0089] like Figure 2As shown, in an optional embodiment, the supporting mechanism 4 includes: a planetary wheel 41; the supporting disk 2 is circular, and a driving gear 21 is arranged on its top surface, and the driving gear 21 is arranged concentrically with the supporting disk 2; the driving gear 21 is rotatably connected to the supporting disk 2; the bottom surface of the supporting disk 2 can be connected to a motor mechanism, and the supporting disk 2 is driven to rotate by the motor mechanism, and the rotation speed of the supporting disk 2 may be different from the rotation speed of the cover plate 1; after the cover plate 1 descends, the driving gear 21 is connected to the cover plate 1, and the first driving mechanism 11 rotates with the cover plate 1; a gear ring 22 is arranged on the top surface of the supporting disk 2; the planetary wheel 41 is arranged on the top surface of the supporting disk 2, and the planetary wheel 41 is located between the driving gear 21 and the gear ring 22; the planetary wheel 41 is meshed with the driving gear 21, and the planetary wheel 41 is meshed with the gear ring 22 ; The planetary wheel 41 is provided with a plurality of through holes 42, in which silicon carbide wafers 6 are placed; the thickness of the planetary wheel 41 is less than the thickness of the gear ring 22, and the silicon carbide wafer 6 is higher than the top surface of the gear ring 22; the distance between the second distance measuring module 32 and the supporting mechanism 4 whose surface is covered with diamond liquid is the distance between the second distance measuring module 32 and the planetary wheel 41 whose surface is covered with diamond liquid; a plurality of grooves may be provided on the top surface of the driving gear 21, and a plurality of plugs may be provided on the bottom surface of the cover plate 1, and the plugs may be inserted into the grooves during the descending process of the cover plate 1, at which time, when the cover plate 1 rotates, the driving gear 21 may be driven to rotate, and the rotation of the driving gear 21 may drive the planetary wheel 41 to rotate and revolve around the driving gear 21; the gear ring 22 may be fixed to an external mechanism so that the gear ring 22 does not rotate with the support plate 2; the rotation and revolution of the planetary wheel 41 may drive the silicon carbide wafer 6 therein to rotate.

[0090] In an optional embodiment, the silicon carbide wafer thickness measurement and control device also includes: a liquid spraying mechanism 5; the liquid spraying mechanism 5 passes through the cover plate 1; the liquid outlet 54 at the bottom of the liquid spraying mechanism 5 is located above the driving gear 21; the liquid spraying mechanism 5 is suitable for configuring diamond liquid, and then the diamond liquid is sprayed between the cover plate 1 and the support plate 2; the silicon carbide wafer 6 can be ground by the diamond liquid.

[0091] like Figure 3As shown, in an optional embodiment, the liquid spraying mechanism 5 includes: a configuration box 51, a connecting pipe 52 and a sleeve 53; the bottom surface of the sleeve 53 is sealed and the top surface is open; the configuration box 51 is arranged above the cover plate 1; the connecting pipe 52 is arranged vertically, and the top end of the connecting pipe 52 is connected to the bottom surface of the configuration box 51; the bottom of the connecting pipe 52 is inserted into the sleeve 53; the sleeve 53 passes through the driving gear 21, and the driving gear 21 is rotatably connected to the outer wall of the sleeve 53 so that the sleeve 53 will not rotate with the driving gear 21; the sleeve A plurality of liquid outlets 54 are equidistantly provided on the side wall of the configuration box 53; the lowest point of the connecting pipe 52 is higher than the liquid outlet 54; the liquid outlet 54 is higher than the top surface of the driving gear 21 to ensure that the diamond liquid can be smoothly sprayed between the cover plate 1 and the support plate 2; a concentration sensor electrically connected to the control module is provided in the configuration box 51, and the concentration sensor is suitable for detecting the concentration of the diamond liquid in the configuration box 51; the diamond liquid in the configuration box 51 enters the sleeve 53 through the connecting pipe 52, and then is sprayed between the cover plate 1 and the support plate 2 through the liquid outlet 54; the diamond liquid can be configured in the configuration box 51.

[0092] In an optional embodiment, a second driving mechanism is connected to the connecting pipe 52, and the second driving mechanism is electrically connected to the control module; the second driving mechanism is suitable for driving the connecting pipe 52 to rise and fall, so as to adjust the length of the connecting pipe 52 extending into the configuration box 51, and the length of the connecting pipe 52 extending into the sleeve 53; a first liquid inlet pipe 55, a second liquid inlet pipe 56 and a feed pipe 57 are arranged on the top surface of the configuration box 51; the first liquid inlet pipe 55, the second liquid inlet pipe 56 and the feed pipe 57 are all connected to the inside of the configuration box 51; the second liquid inlet pipe 56 is located above the connecting pipe 52; polishing liquid is input into the configuration box 51 through the first liquid inlet pipe 55 , diamond sand is input into the configuration box 51 through the feed pipe 57 to prepare diamond liquid in the configuration box 51, the diamond liquid enters the sleeve 53 through the connecting pipe 52, and then is sprayed between the cover plate 1 and the support plate 2 through the liquid outlet 54 to grind the silicon carbide wafer 6; during the grinding process, the top surface of the connecting pipe 52 is first flush with the inner bottom surface of the configuration box 51, at this time, the diamond liquid in the configuration box 51 enters the sleeve 53 through the connecting pipe 52, and then is sprayed out through the liquid outlet 54, when the concentration of the diamond liquid is too high, the connecting pipe 52 will rise and contact the second liquid inlet pipe 56, so that the grinding liquid in the second liquid inlet pipe 56 can dilute the diamond liquid in the connecting pipe 52.

[0093] In an optional embodiment, during the grinding process of the silicon carbide wafer 6, due to the excessive concentration of the diamond liquid, that is, the content of corundum in the diamond liquid is too high, the grinding speed of the silicon carbide wafer 6 is too fast. Even if the thickness of the silicon carbide wafer 6 is detected in real time, it is easy for the silicon carbide wafer 6 to be ground too thin and scrapped due to the reaction time of the control during the grinding process. Therefore, when the grinding speed of the silicon carbide wafer 6 is too fast, the concentration of the diamond liquid needs to be reduced. In the related art, it is necessary to shut down the entire grinding equipment and then prepare a new low-concentration diamond liquid before restarting the equipment for grinding, which will lead to a decrease in grinding efficiency. In addition, shutting down and restarting the equipment during the grinding process will cause the surface quality of the silicon carbide wafer 6 to decrease, and even cause problems such as edge collapse and cracks. The control module is configured to control the second drive mechanism to drive the connecting pipe 52 to rise according to the grinding speed of the silicon carbide wafer 6, that is, the control module makes a judgment based on the speed of change of the thickness of the silicon carbide wafer 6. When the thickness of the silicon carbide wafer 6 is When the preset change speed is exceeded, it is determined that the silicon carbide wafer 6 is ground too fast and the diamond concentration in the diamond liquid is too high. At this time, the control module controls the electromagnetic valve 58 in the connecting pipe 52 to be closed, and then controls the second driving mechanism to drive the connecting pipe 52 to rise, so that the top of the connecting pipe 52 contacts the second liquid inlet pipe 56, opens the electromagnetic valve 58, and inputs the grinding liquid into the connecting pipe 52 through the second liquid inlet pipe 56 to reduce the concentration of the diamond liquid in the connecting pipe 52, and there is no need to shut down the grinding equipment. When the concentration of the diamond liquid is too high, the diamond liquid in the connecting pipe 52 is diluted to a diamond liquid that meets the preset concentration, and the silicon carbide wafer 6 is kept in the grinding process by the diluted diamond liquid. At the same time, the original high-concentration diamond liquid is extracted from the configuration box 51, and a new diamond liquid that meets the concentration requirement is configured. In the process of configuring the new diamond liquid, the diluted diamond liquid in the connecting pipe 52 is used to ensure that the grinding equipment is always grinding the silicon carbide wafer 6, thereby avoiding equipment shutdown and ensuring grinding efficiency.

[0094] In an optional embodiment, when the control module determines that the silicon carbide wafer 6 is ground too fast, after the top of the connecting pipe 52 contacts the second liquid inlet pipe 56, the control module controls the water pump to extract the diamond liquid in the configuration box 51, and the water pump is connected to the inside of the configuration box 51 through a pipeline; after the diamond liquid in the configuration box 51 is extracted, the control module obtains the residual amount of diamond sand in the configuration box 51;

[0095] T=T1+T2+T3;

[0096] T1=C1×ρ×A1;

[0097] T2 = C2 × ρ × A2;

[0098] T3 = C3 × ρ × A3;

[0099] Wherein, T is the total residual amount of corundum, in grams; ρ is the density of corundum, in g / cm³; T1 is the residual amount of corundum on the bottom surface of the configuration box 51, in grams; C1 is the sedimentation coefficient of the bottom surface of the configuration box 51, in cm; A1 is the area of ​​the bottom surface of the configuration box 51, in cm 2 ; T2 is the residual amount of corundum on the inner wall of the configuration box 51, in grams; C2 is the deposition coefficient of the inner wall of the configuration box 51, in cm; A2 is the area of ​​the inner wall of the configuration box 51, in cm 2 ; T3 is the amount of corundum residue on the top surface of the configuration box 51, in grams; C3 is the deposition coefficient on the top surface of the configuration box 51, in cm; A3 is the area of ​​the top surface of the configuration box 51, in cm 2 ; T1>T2>T3, that is, the residual amount on the bottom surface of the configuration box 51 is greater than the residual amount on the inner wall, which is greater than the residual amount on the inner top surface; specifically, T1 can be 0.01, T2 can be 0.008, and T3 can be 0.005.

[0100] In an optional embodiment, after obtaining the residual amount of corundum, the control module configures diamond liquid in the configuration box 51 according to the residual amount of corundum and the preset concentration of diamond liquid. At this time, polishing liquid is input into the configuration box 51 through the first liquid inlet pipe 55, and corundum is input into the configuration box 51 through the feed pipe 57.

[0101] At least one other disclosed embodiment further provides a measurement method using the above-mentioned silicon carbide wafer thickness measurement control device, comprising: the first distance measuring module 31 is suitable for detecting the distance between it and the silicon carbide wafer 6 whose surface is covered with diamond liquid; the second distance measuring module 32 is suitable for detecting the distance between it and the supporting mechanism 4 whose surface is covered with diamond liquid; the control module is configured to obtain the thickness of the silicon carbide wafer 6 according to the distance between the first distance measuring module 31 and the silicon carbide wafer 6 whose surface is covered with diamond liquid and the distance between the second distance measuring module 32 and the supporting mechanism 4 whose surface is covered with diamond liquid during the grinding process.

[0102] In summary, the present silicon carbide wafer thickness measurement and control device comprises: a cover plate 1, a support plate 2 and a detection mechanism 3; the cover plate 1 is located above the support plate 2; at least one bearing mechanism 4 is arranged on the top surface of the support plate 2, and the bearing mechanism 4 is suitable for bearing the silicon carbide wafer 6; the detection mechanism 3 comprises: a first distance measuring module 31 and a second distance measuring module 32 arranged on the bottom surface of the cover plate 1; the first distance measuring module 31 and the second distance measuring module 32 are both electrically connected to the control module; the first distance measuring module 31 is arranged closer to the center of the cover plate 1 than the second distance measuring module 32; the first distance measuring module 31 The control module is suitable for detecting the distance between the first distance measuring module 31 and the silicon carbide wafer 6 with the surface covered with diamond liquid; the second distance measuring module 32 is suitable for detecting the distance between the first distance measuring module 31 and the silicon carbide wafer 6 with the surface covered with diamond liquid and the distance between the second distance measuring module 32 and the supporting mechanism 4 with the surface covered with diamond liquid during the grinding process to obtain the thickness of the silicon carbide wafer 6, thereby realizing the accurate detection of the thickness of the silicon carbide wafer 6 during the grinding process, avoiding the silicon carbide wafer 6 being scrapped due to being ground too thin, and also avoiding the silicon carbide wafer 6 being too thick and requiring rework.

[0103] In the description of the embodiments of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0104] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. is based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, terms such as "first", "second" and other numerical terms do not imply an order or sequence when used in this document unless explicitly indicated above. Therefore, without departing from the teachings of the example embodiments, the first element, component, region, layer or section discussed above may be referred to as a second element, component, region, layer or section.

[0105] Spatially relative terms, such as "inside", "outside", "below", "below", "down", "above", "on", etc., may be used herein to facilitate description of the relationship of one element or feature to another element or feature as illustrated in the figure. In addition to the orientation depicted in the figure, spatially relative terms may be intended to cover different orientations of the device in use or operation. For example, if the device in the figure is turned over, the elements described as "below" or "below" other elements or features will be oriented to be "above" other elements or features. Therefore, the example term "below" can cover the orientation above and below. The device can be oriented in other ways (rotated 90 degrees or in other orientations), and the spatially relative descriptors used herein are interpreted accordingly.

[0106] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A silicon carbide wafer thickness measurement control device, characterized in that: include: A cover plate (1), a support plate (2) and a detection mechanism (3); The cover plate (1) is located above the support plate (2); At least one bearing mechanism (4) is arranged on the top surface of the support plate (2), and the bearing mechanism (4) is suitable for bearing a silicon carbide wafer (6); The detection mechanism (3) comprises: a first distance measuring module (31) and a second distance measuring module (32) arranged on the bottom surface of the cover plate (1); The first distance measuring module (31) and the second distance measuring module (32) are both electrically connected to the control module; The first distance measuring module (31) is arranged closer to the center of the cover plate (1) than the second distance measuring module (32); The first distance measuring module (31) is suitable for detecting the distance between itself and a silicon carbide wafer (6) whose surface is covered with diamond liquid; The second distance measuring module (32) is suitable for detecting the distance between itself and the supporting mechanism (4) whose surface is covered with diamond liquid; The control module is configured to obtain the thickness of the silicon carbide wafer (6) according to the distance between the first distance measuring module (31) and the silicon carbide wafer (6) whose surface is covered with diamond liquid and the distance between the second distance measuring module (32) and the supporting mechanism (4) whose surface is covered with diamond liquid during the grinding process; The support plate (2) is circular, and a driving gear (21) is provided on its top surface; The silicon carbide wafer thickness measurement and control device further comprises: a liquid spraying mechanism (5); The liquid spraying mechanism (5) passes through the cover plate (1); The liquid outlet (54) at the bottom of the liquid spraying mechanism (5) is located above the driving gear (21); The liquid spraying mechanism (5) is suitable for disposing diamond liquid, and then spraying the diamond liquid between the cover plate (1) and the support plate (2); The liquid spraying mechanism (5) comprises: a configuration box (51), a connecting pipe (52) and a sleeve (53); The bottom surface of the sleeve (53) is sealed, and the top surface is open; The configuration box (51) is arranged above the cover plate (1); The connecting pipe (52) is arranged vertically, and the top end of the connecting pipe (52) is connected to the inner bottom surface of the configuration box (51); The bottom of the connecting pipe (52) is inserted into the sleeve (53); The sleeve (53) passes through the driving gear (21), and the driving gear (21) is rotatably connected to the outer wall of the sleeve (53); A plurality of liquid outlets (54) are equidistantly formed on the side wall of the sleeve (53); The lowest point of the connecting pipe (52) is higher than the liquid outlet (54); The liquid outlet (54) is higher than the top surface of the driving gear (21); A concentration sensor electrically connected to the control module is provided in the configuration box (51), and the concentration sensor is suitable for detecting the concentration of the diamond liquid in the configuration box (51); The diamond liquid in the configuration box (51) enters the sleeve (53) through the connecting pipe (52), and then is sprayed between the cover plate (1) and the support plate (2) through the liquid outlet (54); The connecting pipe (52) is connected to a second driving mechanism, and the second driving mechanism is electrically connected to the control module; The second driving mechanism is suitable for driving the connecting pipe (52) to rise and fall, so as to adjust the length of the connecting pipe (52) extending into the configuration box (51) and the length of the connecting pipe (52) extending into the sleeve (53); A first liquid inlet pipe (55), a second liquid inlet pipe (56) and a feed pipe (57) are provided on the top surface of the configuration box (51); The first liquid inlet pipe (55), the second liquid inlet pipe (56) and the feed pipe (57) are all in communication with the interior of the configuration box (51); The second liquid inlet pipe (56) is located above the connecting pipe (52); Grinding liquid is fed into the configuration box (51) through a first liquid inlet pipe (55), diamond grit is fed into the configuration box (51) through a feed pipe (57), so as to prepare diamond liquid in the configuration box (51), the diamond liquid enters the sleeve (53) through a connecting pipe (52), and then is sprayed between the cover plate (1) and the support plate (2) through a liquid outlet (54), so as to grind the silicon carbide wafer (6); The control module is configured to control the second driving mechanism to drive the connecting pipe (52) to rise according to the grinding speed of the silicon carbide wafer (6), that is, The control module makes a judgment based on the speed of change of the thickness of the silicon carbide wafer (6). When the thickness of the silicon carbide wafer (6) exceeds a preset speed of change, it is judged that the silicon carbide wafer (6) is ground too fast and the concentration of diamond grit in the diamond liquid is too high. At this time, the control module controls the electromagnetic valve (58) in the connecting pipe (52) to close, and then controls the second driving mechanism to drive the connecting pipe (52) to rise so that the top of the connecting pipe (52) contacts the second liquid inlet pipe (56), opens the electromagnetic valve (58), and inputs grinding liquid into the connecting pipe (52) through the second liquid inlet pipe (56), so as to reduce the concentration of the diamond liquid in the connecting pipe (52).

2. The silicon carbide wafer thickness measurement control device according to claim 1, characterized in that: The control module is configured to obtain the thickness of the silicon carbide wafer (6) according to the distance between the first distance measuring module (31) and the silicon carbide wafer (6) whose surface is covered with diamond liquid and the distance between the second distance measuring module (32) and the supporting mechanism (4) whose surface is covered with diamond liquid during the grinding process, that is, The thickness of the silicon carbide wafer = (the distance between the second distance measuring module (32) and the supporting mechanism (4) whose surface is covered with diamond liquid - the distance between the first distance measuring module (31) and the silicon carbide wafer (6) whose surface is covered with diamond liquid) + the thickness of the supporting mechanism; Wherein, the thickness of the bearing mechanism (4) is preset in the control module; The cover plate (1) is connected to a first driving mechanism (11), the first driving mechanism (11) being suitable for driving the cover plate (1) to rise and fall and rotate, and the first driving mechanism (11) being connected to a control module; When the thickness of the silicon carbide wafer (6) reaches a preset standard value, the control module controls the first driving mechanism (11) to stop.

3. The silicon carbide wafer thickness measurement control device according to claim 2, characterized in that: The bearing mechanism (4) comprises: a planetary wheel (41); The support plate (2) is circular, and a driving gear (21) is arranged on the top surface thereof, and the driving gear (21) is arranged concentrically with the support plate (2); After the cover plate (1) descends, the driving gear (21) is connected to the cover plate (1), and the first driving mechanism (11) rotates along with the cover plate (1); A toothed ring (22) is provided on the top surface of the support plate (2); The planetary wheel (41) is arranged on the top surface of the support plate (2), and the planetary wheel (41) is located between the driving gear (21) and the gear ring (22); The planetary wheel (41) meshes with the driving gear (21), and the planetary wheel (41) meshes with the gear ring (22); The planetary wheel (41) is provided with a plurality of through holes (42), and silicon carbide wafers (6) are placed in the through holes (42); The thickness of the planetary wheel (41) is less than the thickness of the gear ring (22), and the silicon carbide wafer (6) is higher than the top surface of the gear ring (22); The distance between the second distance measuring module (32) and the supporting mechanism (4) whose surface is covered with diamond liquid is the distance between the second distance measuring module (32) and the planetary wheel (41) whose surface is covered with diamond liquid.

4. The silicon carbide wafer thickness measurement control device according to claim 1, wherein: When the control module determines that the silicon carbide wafer (6) is ground too fast, after the top of the connecting pipe (52) contacts the second liquid inlet pipe (56), the control module controls the water pump to extract the diamond liquid from the configuration box (51), and the water pump is connected to the inside of the configuration box (51) through a pipeline; After the diamond liquid in the configuration box (51) is extracted, the control module obtains the residual amount of diamond sand in the configuration box (51); T=T1+T2+T3; T1=C1*ρ*A1; T2=C2*ρ*A2; T3=C3*ρ*A3; Wherein, T is the total amount of corundum remaining; ρ is the density of corundum; T1 is the amount of corundum remaining on the inner bottom surface of the configuration box (51); C1 is the deposition coefficient of the inner bottom surface of the configuration box (51); A1 is the area of ​​the inner bottom surface of the configuration box (51); T2 is the amount of corundum remaining on the inner side wall of the configuration box (51); C2 is the deposition coefficient of the inner side wall of the configuration box (51); A2 is the area of ​​the inner side wall of the configuration box (51); T3 is the amount of corundum remaining on the inner top surface of the configuration box (51); C3 is the deposition coefficient of the inner top surface of the configuration box (51); A3 is the area of ​​the inner top surface of the configuration box (51).

5. The silicon carbide wafer thickness measurement control device according to claim 4, characterized in that: After obtaining the residual amount of corundum, the control module configures diamond liquid in the configuration box (51) according to the residual amount of corundum and the preset concentration of diamond liquid. At this time, polishing liquid is input into the configuration box (51) through the first liquid inlet pipe (55), and corundum is input into the configuration box (51) through the feed pipe (57).

6. A measurement method using the silicon carbide wafer thickness measurement control device as claimed in claim 1, characterized in that: include: The first distance measuring module (31) is suitable for detecting the distance between itself and a silicon carbide wafer (6) whose surface is covered with diamond liquid; The second distance measuring module (32) is suitable for detecting the distance between itself and the supporting mechanism (4) whose surface is covered with diamond liquid; The control module is configured to obtain the thickness of the silicon carbide wafer (6) according to the distance between the first distance measuring module (31) and the silicon carbide wafer (6) whose surface is covered with diamond liquid and the distance between the second distance measuring module (32) and the supporting mechanism (4) whose surface is covered with diamond liquid during the grinding process.

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