LU501218B1 - Manufacturing method of piezoresistive acceleration sensor based on silicon carbide material - Google Patents

Abstract

A manufacturing method of piezoresistive acceleration sensor based on silicon carbide material, which adopts the double cantilever beam design, and designs the resistance strips and circuit layout positions with resistance changing with stress to form the Wheatstone Bridge. The sensitive element substrate is silicon carbide, the resistor is doped silicon carbide material, and the surface wiring material is gold. This invention provides the package design of the whole device, including the glass upper cover and the bottom silicon-based package are used as the limit, and the ceramic package. It uses silicon processing technology, the silicon-based inner shell substrate can provide accurate vibration margin and protection limit. Through the gold wire ball bonding process, the input and output signals of the four pads of the sensor chip are led to the four metal pins on the side of the metal shell, and the 50 micron gold wire signal transmission is adopted.

Description

Description 0501218 Manufacturing method of piezoresisiive acceleration sensor based on silicon carbide materiai Technical Neid The invention relates to the technical field of electronic components, in particular to manufacturing method of piezorssisiive acceleration sensor based on silicon carbide material Background Up to now, MEMS acceleration sensors have occupied a considerable proportion in the market and has been commonly used. For example, the MEMS acceleration sensor that is independently developed and manufactured by Qingdac Zhileng Company in China adopts MEMS process flows such as etching and packaging, which achieves bias stability of 0.24 ~ 6, working temperature of -40°C ~ 125°C and measuring range of 2 ~ 50g, and has been successfully used in aerospace vehicles. Moreover, the sensor uses the doped silicon carbide material with excellent high-temperature performance as ithe substrate of the sensitive element, thus realizing the sensor sensitive element with better working performance at high temperature, Ab present, the properties of the most of materials which can be used in MEMS processing will be changed, or will be damaged to fai in high temperature environment, which limits the operating temperature tolerance of MEMS devices. Sensors require extremeiy high performance of sensitive components, so acceleration detection in high temperature environment has always been a challenging factor in the sensor field. Furthermore, in the MEMS processing, the processing and manufacturing methods of silicon carbide materials are also the main problems that imit the development of silicon carbide substrate components.

Summary in order to solve the technical problems in the prior art, the embodiment of the present disclosure provides method and device for predicting the numerical control machining state based on resi-time data and STEF-NC data. This method is LUs01218 accomplished by proposing MEMS acceleration sensor that can work in high temperature environment, aiming at solving the processing difficulties of silicon carbide materials and providing sensor sensitive element that can work normally at high temperature.

in one aspect, the smbodiment of the present disclosure provides a Diexoresistive acceleration sensor based on silicon carbide material, which comprises sensitive element substrate, resistor and surface wiring material, The subsirate of that sensitive element is silicon carbide, the resistor is a component made of silicon carbide material doped by a preset threshold degree, and the surface route material is gold.

In one embodiment, the Diezoresistive acceleration sensor further comprises a glass upper cover, a bottom silicon substrate and a ceramic tube shell, in another embodiment, the blezoresistive acceleration sensor further comprises a silicon-based internal package substrate configured to provide vibration margin and protection limit with preset accuracy.

in one embodiment, the piezoresistive accelsration sensor is based on piezoresistive effect and designed with double cantilever baams.

in another aspect the disclosed embodiment provides a manufacturing method of piezoresisiive accsleration sensor based on silicon carbide material, which comprises the following steps: Etch the epitaxiai laver of SIC wafer by resistance lithography with a front dry etching machine, and form a resistance pattern. Use SiD» to protect the spacer, and eich the window at the preset position to finish the photostching operation of the dielectric hole, Etch the hollowed-out part of the component to a preset depth by front deep groove lithography, and control the thickness of the cantilever beam where the resistor bar is located by the preset depth. Ohmic contact is formed at the SiDa window position of the resistor strip by Hft-off process, Manufacture components into pads by metal wiring lithography method, and form metal interconnection with the ohrmic contact, the back thinning of the metal interconnection part is completed through cleaning operation, front glue leveling operation and front bonding operation 0501218 in turn, then, the processed metal interconnection part sequentially pui through sputtering operation, photosiching operation, developing operation, film hardening operation, bottom film operation, metal corrosion operation and eiching operation to complets the back hole photosiching operation.

in one embodiment, i alse includes: preparing à mask plate of silicon carbide. The preparation of the mask plats of silicon carbide includes the following steps: processing silicon carbide and overly a plurality of mask plates.

in addition, in one embodiment, i should be noted that the metal interconnection cart is thinned on the back side by cleaning operation, front glug leveling operation and front bonding operation in sequence for twice, The mverdion provides a piezoresistive acceleration sensor based on silicon carbide material and a manufacturing method thereof. The core sensitive element of the piezoresistive acceleration sensor is based on pisrorasistive effect, which adopts double cantilever beam design and designs the arrangement position of resistance bars and circeuils whose resistance changes wilh stress ic form a complete Wheatstone bridge. The sensitive slement substrate is sidicon carbide, the resisior is highly doped silicon carbide material, and the surface wiring material is gold. Further, this invention provides the package design scheme of the whole device, including the glass upper cover and the bottom silicon-based package used as the mit, and the package design of the ceramic package. The invention uses silicon processing technology to obtain the high-precision silicon-based inner shell substrate that can provide accurate vibration margin and protection limit, By executing the Gold wire ball bonding process, the input and output signals of the four pads of the sensor chip are led to the four metal pins on the side of the metal shell, and 50 micron gold wires are used for signal transmission Lo ensure the stability of signal transmission and the high temperature safely of the chip.

Brief Description Of The Figures LUs01218 in order to more clearly explain the technical scheme of the embodiment of the present disclosure, the following is a brief introduction to the Figures needed in the description of the embodiment: Fig. 1 is a schematic flow diagram of the steps of a manufacturing method of pieroresisiive acceleration sensor based on silicon carbide material in one embodiment of the present Invention.

Fig. 2(a)-{c) are the top view and schematic circuit design diagram of silicon carbide acceleration sensor in the manufacturing method of piezoresistive acceleration sensor based on silicon carbide material in ons embodiment of the present invention.

Fig. 318 a schematic cross-sectional view of a silicon carbide acceleration sensor in a manufacturing method of à piezoresistive acceleration sensor based on silicon carbide materials in one embodiment of the present invention.

Fig, 4 is a three-dimensional schematic diagram of the bottom silicon-based package in the manufacturing method of a piezoresistive acceigration sensor based on silicon carbide material in one embodiment of the present invention, Fig. 5 is a schematic diagram of a ceramic package scheme in a manufacturing method of a piezoresistive acceleration sensor based on silicon carbide materials in one embodiment of the present invention, Fig. 6 is a schematic diagram of silicon carbide processing mask plats in the manufacturing method of piezoresistive acceleration sensor based on silicon carbide material in one embodiment of the present invention, Fig. 7 is a schematic diagram of silicon carbide machining mask plate engraving in the manufacturing method of piezoresistive acceleration sensor based on silicon carbide material in one embodiment of the present invention.

Fig. 8 is a schematic diagram of the processing flow of silicon carbide in the manufacturing method of piezoresistive acceleration sensor based on silicon carbide material in one embodiment of the present invention,

Fig. S is a schematic diagram of a silicon carbide photoresist plais in a 0501218 manufacturing method of a piezoresistive acceleration sensor based on silicon carbide materials in one embodiment of the present invention.

Fig. 10 is a schematic diagram of silicon carbide resistor processing flow in a manufacturing method of a piezoresistive acceleration sensor based On silicon carbide materials in one embodiment of the present invention, Fig. 11 is a schematic diagram of SEM observation of silicon carbide resistance etching pattern in the manufacturing method of piezoresistive acceleration sensor based on silicon carbide material in one embodiment of the present invention, Fig. 12 is a schematic diagram of an insulating dielectric hole pnotoresist plate in a manufacturing method of a piezoresistive acceleration sensor based on silicon carbide materials in one embodiment of the present invention, Fig. 13 is a schematic diagram of insulating dielectric hole iithography in the manufacturing method of pigzoresistive acceisration sensor based on SIBCON carbides material in one embodiment of the present invention, Fig. 14 is a schematic view of optical microscope observation after stching the insulating dieleciric hole in the manufacturing method of piezoresistive acceleration sensor based on silicon carbide material in one embodiment of the present invention, Fig. 15 is a schematic diagram of a front deep groove etching photoresist plate in a manufacturing method of 2 piesoresisiive acceleration sensor based on silicon carbide materials in ons embodiment of the present invention.

Fig. 16 is a schematic diagram of front deep groove etching in the manufacturing method of piezoresistive acceleration sensor based on silicon carbide material in one embodiment of the present invention.

Fig. 17 is a schematic view of optical microscope observation after etching the front deep groove in the manufacturing method of piezoresistive acceleration sensor based on silicon carbide material in one embodiment of the present invention.

Fig. 18 is a schematic diagram of an ohmic contact photoresist plate in a manufacturing method of a piezoresistive acceleration sensor based on silicon carbide materials in one embodiment of the present invention.

Fig. 19 is a schematic diagram of ohmic contact lithography in the manufacturing 0501218 method of a piezoresistive acceleration sensor based on silicon carbide material in one embodiment of the present invention, Fig. 20 is a schematic diagram of microscopic observation ohmic contact graphic in the manufacturing method of piezoresistive acceleration sensor based on silicon carbide material in one embodiment of the present invention.

Fig. 21 1s a schematic diagram of ohmic contact graphic observed by optical microscope in the manufacturing method of plezoresistive acceleration sensor based on silicon carbide material in one embodiment of the present invention.

Fig 22 is a schematic diagram of SEM observation ohmic contact graphic in the manufacturing method of piezoresistive acceleration sensor based on silicon carbide material in one embodiment of the present invention, Fig. 23 18 a schematic diagram of an optical microscope observing the graphic of metal wiring after lithography in the manufacturing method of 8 piezorssistive acceleration sensor based on silicon carbide material in one embodiment of the present invention.

Fig. 24 is a schematic diagram of an optical microscope observing the graphic of meatal wiring after pesling in a manufacturing method of a piezoresistive acceleration sensor based on silicon carbide material in one embodiment of the present invention.

Fig. 25 18 à simple cross-sectional example diagram of cantilever beam process in the manufacturing method of piezoresistive acceleration sensor based on silicon carbide material in one embodiment of the present invention.

Description of the present invention in the following, the application will be described in further detail with reference to the Figures and embodiments.

in the following introduction, the terms "first" and “second” are for descriptive purposes only, and cannot be understood as indicating or implying relative importance. The following description provides a number of embodiments of the present disclosure, and different embodiments can be repiaced or combined, so this application can alse be considered to include ail possible combinations of the same 0501218 and/or different embodiments described. Therefore, if one embodiment contains features A B, © and another embodiment contains features B, D, then this application should also be regarded as an embodiment containing ons or mors other possible combinations of & 5, ©, D although this embodiment may not be explicitly described inthe following contents.

In order to make the purpose, technical scheme and advantages of the present invention more clear, the piezoresistive acceleration sensor based on silicon carbide material and its manufacturing method will be further described in detail followings through embodiments and Figures, it should be understood that the specific embodiments described here are only used to explain the invention, and are not used to limit the invention, in ons embodiment, a piezoresistive acceleration sensor based on silicon carbide material is disclosed. Specifically, the piezoresistive acceleration sensor includes: sensitive element substrate, resistor and surface wiring material. The substrate of this sensitive element is silicon carbide, the resisior is a component made of silicon carbide material doped by a preset threshold degree, and the surface route material is gold. In addition, à should be noted that the piezoresistive acceleration sensor also includes a glass upper cover, a silicon-based bottom ube shell and a ceramic tube shail.

Furthermore, in one embodiment, the piezorasistive acceleration sensor further comprises a silicon-based internal package substrate configured to provide a vibration margin and protection mits with preset accuracy.

Furthermore, in one embodiment, the piezoresistive acceleration sensor is based on pierorasistive effect and designed with double cantilever beams.

As shown in Fig. 1, is a schematic flow diagram of manufacturing method of piezoresistive acceleration sensor based on Silicon carbide material in one embodirment, which specifically includes the following steps: S101, the epitaxial layer of SIC wafer is eiched by resistance lithography with a front dry stching machine, and a resistance pattern is formed.

S102, protect the spacer with Si0>, and etch the window al the preset position fo 0501218 finish the photosiching operation of the dislectric hole.

S103; Eich the hollowed-oui part of the component to a preset depth by front deep groove lithography, and control the thickness of the cantilever where the resistor bar is located by the preset depth.

S104, ohmic contact is formed at the SiO window position of the resistor strip by the lift-off process.

S105, the components are made into pads by metal wiring lithography, and metal interconnection is formed with the ohmic contact.

5106, the back thinning of the metal interconnection part is completed through cleaning operation, front giue leveling operation and front bonding operation in tum.

S107, the processed metal interconnection part is sequentially put through sputtering operation, photolithography operation, developing operation, film hardening operation, bottom film operation, metal corrosion operation and eiching operation to complete the back hole photolithography operation in addition, in one embodiment, the method further comprises preparing a mask plate of silicon carbide. The preparation of mask plates of silicon carbide includes: processing silicon carbide, and overly a plurality of mask plates.

in addition, in one embodiment, i should be noted that the metal interconnection part is thinned on the back side by cleaning operation, front glue leveling operation and front bonding operation in sequence for twice.

in order to more clearly understand and apply the manufacturing method of Diexoresistive acceleration sensor based on sihoon carbide material proposed in this disclosure, the following embodiments are made. it should be noted that the scope protected by this disciosure is not limited to the following embodiments, With reference to Fig 2-Fig 25, specifically, the core sensitive element of piezoresistive acceleration sensor designed in this disclosure is based on piezoresistive affect, which adopis the design of double cantilever beams, as shown in Fig. Zia){(c), and the resistance bars and circuits with resistance changing with stress are arranged as shown in Fig. 2(8)-{c} form the Whealstone bridge. In addition, as shown in Fig. 3, the substrats of the sensitive element is silicon carbide, the resistor 0501218 strip is finished by heavy N doping of silicon carbide and low P doping of silicon carbide successively, and the wire material is gold.

Further, this disclosure puts forward the package design scheme of the whole device, including the glass upper cover and the bottom silicon-based package used as limiting devices, and the package design of the ceramic package, as shown in Fig à and 5. Use silicon processing technology, the high-precision silicon-based inner shell substrate can provide accurate vibration margin and protection limit Through the gold wire ball bonding process, the input and output signals of the four pads of the sensor chip are led to the four meta! pins on the side of the metal shell, and 50 micron gold wires are used for signal transmission Io ensure the stability of signal transmission and the high temperature safety of the chip.

Furthermore, the invention also discloses manufacturing method of the core sensitive element of the acceleration sensor based on silicon carbide, which includes resistance lithography, dielectric hole Bthography, front desp groove Hihography, shmic contact hthography, metal wiring Hthography, back thinning and back hole lithography with six MASK plus one thinning. First, the mask plais of silicon carbide is prepared as shown in Figure 6 for the preliminary graphic preparation and processing preparation of high-temperature resistant silicon carbide acceleration sensor, then, Fig. 7 is a schematic diagram of six masks after engraving. The processing flow diagram of silicon carbide is shown in Fig, & it is necessary io further explain the machining accuracy: front overlay accuracy is not less than Zum, and the back overly accuracy is not less than Sum. Graphic line width error is not more than 2um. The film deposition thickness is based on the ability to output electrical signals, which can be adjusted with the processing party, and the error is not required. Etching depth error is not more than Zum, verticality is not required, and His as Close as possible to 80. In addition, the requirements for cutting package: the chip can be packaged independently, and the voltage signal can be output at the chip pin.

Specifically, the main goal of resistance lithography is to eich the epitaxial layer of 0501218 SIG material from the front and form a resistance pattern. The photoresisi plate and simple flow chart are shown in Fig 8 11, Specifically, dry eiching machine is used to sich the epitaxial layer of SIC wafer, and the pattern with good shape and meeting the process requirements is obtained, as shown in Fig 11.

The main purpose of the process stage of disiectric lithography is to use SI: to protect the spacer and eich the window at the required position for the subsequent process, The photoresist plate and simple flow chart are shown in Fig 12- Fig. 14, Specifically, SiQ> is etched by normal etching machine, and the pattern meeting the process requirements is obtained, as shown in Fig 14.

The main purpose of the process stage of front deep trench lithography Is Io etch the front of the hollowed out part of the device to a certain depth, and io control the thickness of the cantilever where the resistor strip is located by the depth. The photoresist plate and simple flow chart are shown in Fig 15- Fig. 17. In addition, the main purpose of the Ohmic contact lithography process stage is to form chmic contact in the lift-off process ai the SiOx window position of the resistor strip.

The photoresist plate and simple flow chart are shown in Fig. 18- Fig, 22. Further, the main purpose of the photolithography process stage of the gold tertiary wiring is to make pad and form metal interconnection with ohmic contact, The specific flow chart is shown in Fig. 23- Fig, 24.

Further, the process stages of back thinning mainly include cleaning, front leveling protection and front bonding. Specifically, regarding the cleaning operation, that is, before the process, id is necessary to ensure the cleanliness of the front and back of the material. The front process of SIG wafer has been completed, and the impurity contamination on the left front will cause the front device to be damaged in the subsequent process, and will directly affect the subsequent back exposure process. The back of the wafer is the thinning surface required by this process, and the contamination of larger particles and impurities should be avoided to prevent the subsequent thinning effect from being affected, After NMP soaking, ethanol washing and deionized water washing, SIC was cleaned Ensure the cleanliness of the 0501218 material Regarding the front-side leveling protection, that is, before the bonding process, it is necessary to perform leveling protection on the front-side devices of SIC wafer When using low-temperature wax (melting point is about 85) for bonding, photoresist with moderate viscosity can be simply used as leveling adhesive, Prevent floc contamination when spinning the front surface of SIC wafer. After glue leveling, the glue leveling table should be cleaned in time fo prevent contamination. At the same time, the comers on the back of the wafer should be Cleaned to ensure the uniformity of gluse leveling. After the glue leveling, the SIC wafer is placed on the hot stage for baking, and after cooling, the thickness of 5 points in the plane is measured by the thickness tester. The next bonding process can be continued if the thickness difference of à points on the front is less than 10um.

Regarding the front bonding, that is, the sapphire holder whose uniformity accords with the process is selected, and the SiC wafer is bonded with the sapphire holder by using high-temperature wax. Afler bonding, S-point in-plane thickness measurement is carried out by thickness tester. if the thickness measurement difference of 5 points on the front is less than 10um, the next process can be continued. Continue to bond the back of the sapphire holder with the special glass holder, and then measure the thickness of the front of the wafer again after bonding. Generally speaking, this step has little influence on the uniformity of bonding of the previous wafer, and the measured vaiue this time should be basically consistent with the previous one.

in addition, it should be noted that the manufacturing method of piezoresistive acceisration sensor based on silicon carbide material proposed in this disciosure includes: resistance lithography, dielsctrc hole lithography, front deep groove Hthography, ohmic contact lithography, metal wiring lithography, back thinning and back hole lithography with sic MASK plus one thinning.

Specifically, the back thinning refers to placing the SIC wafer Io be thinned face up on the fiture, and after confirming that the back glass holder is vacuum-absorbead,

selecting appropriate grinding liquid and using the thinning machine to start wafer 0501218 thinning. After many tests and adiusiments, this process ensures that the back of SIC water is thinned, and the wafer structure is intact without obvious scratches. it lays a solid foundation for the development of subsequent back hols etching process.

Furthermore, the back hole Hthography process stages include sputtering, lithography, development, film hardening, primer Alm, metal corrosion and etching. Specifically, with regard to the spullering process, that is, through the ressarch on deep groove etching of SIC in the front part of this processing process, the deep groove siching experience is mainly used in the back elcting of SIC in this process, and the process is appropriately adiusted in combination with the characteristics of back etching to achieve the expected effect In this process, metal is still selected as the mask for SIC etching. According to the SiC/ metal stching selectivity ratio which has been investigated in the previous process, KS-400 is used for sputtering to obtain the mask needed for this back etching.

in addition, regarding the photolithography process, that is, consistent with the front deep groove etching process, the metal mask is patterned by photolithography process. Leveling glue: spin a uniform layer of photoresist on the SiC wafer with sputierad metal Uniike the front etching process, the wafer in this process is a quarter size 4-inch wafer, and after bonding, thinning and sputtering process, it is siili fixed on the sapphire holder, and its internal stress has changed io some exient In the process of leveling glue, extra care should be taken, and the centering should be strictly accurate, 50 as to prevent cracks and falling off during the high-speed rotation of leveling gluse. Pre-baking: the SIC wafer with uniform photoresist is placed on a hot plate for baking. Exposure: mask aligner is used fo expose SIC wafer, and the process parameters are the same as that of front desp groove etching. Contact exposure should reduce the pressure of photoresist plate on wafer to prevent crushing wafer. In addition, this process is double-sided exposure, and the alignment mark is on the SiC water on the back side of the sapphire holder, Through the transparent sapphire holder, the multilayer structure of high-temperature wax can be observed. This requires the front-end process to ensure the full cleaning of the front surface of SIC wafer before bonding. Impurities will block the alignment marks, resulting in difficulties 0501218 in alignment and abnormal exposure.

Further, regarding the development process, that is, using developper to develop the exposed SIC, the process parameters are the same as that of desp french etching on the front side. Hf should be noted that the thinned SIC wafer is fragile, and the operation should be paid attention to prevent debris. Especially when purging the water with nitrogen, the pressure of nitrogen gun should be properly controlled, In addition, regarding the film hardening process, that is, after the photoresist pattern is transferred, the SIC wafer is placed on a hot plate for film hardening, and the process parameters are the same as the front deep groove efching. Compared with the front deep groove etching, the metal mask used in the back siching is thicker, and the etching time is 1.5 times that of the front efching, which is more likely to cause lateral drilling. Therefore, the film hardening time can be appropriately increased, or the film hardening can be carried out by oven baking. In addition, regarding the primer film process, that is, using Trvmax, the SIC wafer is subjected to the primer film process, and the process parameters are the same as the front deep groove etching, Furthermore, regarding the process of metal etching, that is, after the completion of the photolithography process, we conduct a wel etching process on the metal mask of SIG wafer, and the process parameters are basically the same as those of the front deep groove stitching. In addition, regarding the etching process, that is, using S dry giching machine to eich SIC, the elching menu is the same as that of front deep groove etching. After many experiments, the back etching of this process is carried out by using the front deep groove siching process menu, The deep groove hole patiern can be stably obtained. Different from the front deep groove eiching process, the back eiching needs to accurately judge and control the etching end point. The giching process is shown in Fig 25, As shown in Fig 25, after the front desp groove stching and the back hole etching, the device forms a zigzag structure, and the middle part is supported by only two cantilever beams. The thickness of cantilever beam structure is determined by the etching depth on the front and the etching depth on the back. How to control the back etching depth is very important for this process.

Reducing the etching rate near the end of stitching can contra! the thickness of 0501218 cantilever beam more accurately.

To sum up, the manufacturing method of piezoresistive acceleration sensor based on silicon carbide material proposed in this disclosure can detect the vibration situation and movement acceleration data of the measured oblect in real time, and the silicon carbide substrate sensitive element can withstand extremely high temperature, and the measuring range is large. It can realize the complete processing process of silicon carbide substrats material, reasonably solve the processing difficulties such as etching, ohmic contact, wire bonding and so on, and provide accurate process information for the processing and manufacturing of piezoresistive silicon carbide-based acceleration sensors.

The invention provides piezoresistive acceleration sensor based on silicon carbide material and its manufacturing method thereof. The core sensitive element of the piezoresistive acceleration sensor is based on piexoresistive effect, which adopts double cantilever beam design, and designs the arrangement position of resistance Gars and circuits whose resistance changes with stress to form a complete Huitong bridge, The sensitive element substrate is silicon carbide, the resisior is doped silicon carbide material, and the surface wining material is gold. Further, the package design scheme of the whole device is put forward, including the glass upper cover and the bottom silicon-based package used as the limit, and the package design of the ceramic package. Using silicon processing technology, the high-precision silicon-based inner shell substrate can provide accurate vibration margin and protection limit Through the gold wire ball bonding process, the input and output signals of the four pads of the sensor chip are led to the four metal pins on the side of the metal shell, and 50 micron gold wires are used for signal transmission Io ensure the stability of signal transmission and the high temperature safety of the chip.

The embodiment of that invention also provide a computer-readable storage Medium on which à computer program IS store, which is executed by the processor in Fig1.

The embodiment of the invention aise provides 3 computer program product 0501218 containing instructions. This computer program product, when run on a computer, causes the computer io perform the above-mentioned method of Fig. 1.

it can be understood by those skilled in the art that ail or part of the processes in the above-mentioned methods can be completed by instructing related hardware through computer programs, which can be stored in a compuler-readabls storage medium and, when execuisd, can include the processes of the above-mentionad methods, The storage medium can be a magnetic disk, an optical disk, a Read-Only Memory (ROM) or a Random AccessMemory (RAM).

The shove-mentionad embodiments only express several embodiments of the present invention, and their descriptions are more specific and detailed, but they cannot be undersiood as limiting the patent scope of the present invention, it should be pointed out that for ordinary technicians in this field, without departing from the concept of the present invention, several changes and improvements can be made, which are within the scope of protection of the present invention, Therefore, the scope of protection of the patent of the present invention shouid be subject to the appended claims.

The basic principles of this disclosure have been described above in connection with specific embodiments, but it should be pointed out thal the advantages, advantages and effects mentioned in this disclosure are only embodiments rather than limitations, and they cannot be considered as necessary for each embodiment of this disclosure. in addition, the specific details of the above disclosure are only for the purpose of example and understanding, not imitation, The above details do not mit the disclosure to be realized with the above specific details.

The block diagrams of devices, devices, equipment and systems involved in the disclosure of this invention are only exemplary embodiments and do not intend Io require or imply that they must be connected, arranged and configured in the way shown in the block diagrams. As those skilled in the art will realize, theses devices, devices, equipment and systems can be connected, arranged and configured in any way. Words such as "including", “containing”, “having” and so on are open words,

which mean ‘including but not limited to” and can be used interchangeably with them. 0501218 As used herein, the words "or" and "and" refer to the words "and/or" and can be used interchangeably with them, unless the context clearly indicaiss otherwise. As used herein, the word "such as” refers to the phrase "such as but not limited Io” and can be used interchangeably with rt in addition, as used herein, "or" used in the enumeration of items beginning with ‘at least one” indicates a separate enumeration, for example, the enumeration of at least one of A, Bor ©" means Aor Bor ©, or AB or AC or BG, or ABC (ie. a and b and c). Furthermore, the word “exemplary” does not mean that the described example is preferred or better than other embodiments.

The above description has been given for the purpose of illustration and description, Furthermore, this description is not intended to limit the embodiments of the present disclosure io the forms disclosed herein. Although many example aspects and embodiments have been discussed above, those skilled in the art will recognize some variations, modifications, changes, additions and subcombinations thersof.

Claims (1)

Claims LU501218

1. Manufacturing method of piezoresisiive acceleration sensor based on silicon carbide material, which comprises the following steps: etching the epitaxial layer of SIC wafer by resistance lithography with a front dry etching machine, and forming a resistance pattern, use SiOx io protect the spacer, and eich the window at the press position to finish the pholoetching operation of the disiectric hole, etchino the hollowed-out part of the component to a preset depth by front deep groove hihography, and controlling the thickness of the cantilever beam where the resistor bar is located by the preset depth, ohmic contact is formed at the SiO window position of the resistor strip by Hoff process, manufacturing components Into pads by metal wiring lithography method, and forming metal interconnection with the ohmic contact, the back thinning of the metal interconnection part is completed through cleaning operation, front glue leveling operation and front bonding operation in sequence, next, the processed metal interconnection part is sequentially put through sputtering operation, photostching operation, developing operation, film hardening operation, bottom film operation, metal corrosion operation and etching operation ic complete back hole photcetcting operation, the manufacturing method also includes preparing mask plate of sicon carbide, and cleaning operation and two times of cleaning operation, front glue leveling operation and front bonding operation are executed in sequence to complete the back thinning of the metal interconnection part.