CN109132994A

CN109132994A - MEMS electrode microbridge forming method

Info

Publication number: CN109132994A
Application number: CN201810757203.3A
Authority: CN
Inventors: 刘善善; 朱黎敏; 朱兴旺
Original assignee: Shanghai Huahong Grace Semiconductor Manufacturing Corp
Current assignee: Shanghai Huahong Grace Semiconductor Manufacturing Corp
Priority date: 2018-07-11
Filing date: 2018-07-11
Publication date: 2019-01-04

Abstract

The invention discloses a kind of MEMS electrode microbridge forming methods, include the following steps: step 1, prepare a silicon substrate, band sacrificial layer amorphous silicon membrane is formed on the silicon substrate, covers SiO2 on the amorphous silicon membrane；Step 2 is formed by formation contact electrode layer amorphous silicon film on silicon wafer in step 1；Step 3 sequentially forms electrode layer TiN and surface SiO2 on the contact electrode layer amorphous silicon film, and graphical；The surface SiO2 that step 4, etch step 3 are formed, exposes electrode layer TiN；Step 5, wet etching electrode layer TiN form figure.The present invention can completely form MEMS electrode micro-bridge structure.

Description

MEMS electrode microbridge forming method

Technical field

The present invention relates to semiconductor integrated circuit fields, frequent more particularly to a kind of MEMS (MEMS) sensor The MEMS electrode forming method used.

Background technique

Amorphous silicon is the allotropic form of silicon, can be deposited in the form of a film on various substrates, is various electronics Using the certain unique functions of offer.Amorphous silicon is used in the MEMS (MEMS) and Nano electro-mechanical system of large-scale production (NEMS), solar battery, microcrystal silicon and micro- amorphous silicon, even for the rolling technology technology on various substrates be all useful 's.

Summary of the invention

The technical problem to be solved in the present invention is to provide a kind of MEMS electrode microbridge forming methods, can completely be formed MEMS electrode micro-bridge structure.

In order to solve the above technical problems, MEMS electrode microbridge forming method of the invention, includes the following steps:

Step 1 prepares a silicon substrate, band sacrificial layer amorphous silicon membrane is formed on the silicon substrate, in the amorphous silicon membrane Upper covering silica (SiO2)；

Step 2 is formed by formation contact electrode layer amorphous silicon film on silicon wafer in step 1；

Step 3 sequentially forms electrode layer TiN and surface SiO2 on the contact electrode layer amorphous silicon film, and graphical；

The surface SiO2 that step 4, etch step 3 are formed, exposes electrode layer TiN；

Step 5, wet etching electrode layer TiN form figure.

MEMS electrode micro-bridge structure can completely be formed using the present invention, especially form the three of bridge structure in electrode etch In Mingzhi's structure.Method of the invention can prevent stripping glue effect of photoresist during etching TiAlN thin film, and in microbridge Microbridge caused by being effectively relieved because of structural stress when structure release collapses.

The present invention is suitable for MEMS product.

Detailed description of the invention

Present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments:

Fig. 1 is shown one embodiment flow chart of MEMS electrode microbridge forming method；

Fig. 2 is that existing MEMS electrode microbridge forming method and MEMS electrode microbridge formation process method of the invention compare Flow diagram.

Specific embodiment

It referring to Fig. 1 and combines shown in Fig. 2 (d)~(h), the MEMS electrode microbridge forming method is on SiO2 substrate MEMS electrode micro-bridge structure is formed, is included the following steps:

Step 1, in conjunction with shown in Fig. 2 (d) (silicon wafer with TIN film) prepare a silicon substrate, are formed on the silicon substrate Band sacrificial layer amorphous silicon membrane, covers silica (SiO2) on the amorphous silicon membrane；The band sacrificial layer amorphous silicon membrane CVD (chemical vapor deposition) film build method is adopted as to be formed.

Step 2, in conjunction with shown in Fig. 2 (e) (silicon wafer of film forming SiO2) are formed by formation electrode on silicon wafer in step 1 and connect Contact layer amorphous silicon film.

Step 3, in conjunction with shown in Fig. 2 (f) (silicon wafer after smearing photoresist exposure), in the contact electrode layer amorphous silicon film On sequentially form electrode layer TiN and surface SiO2, and it is graphical；The electrode layer TiN using PVD (physical vapour deposition (PVD)) or CVD film build method is formed, and SiO2 is formed using CVD film build method.

Step 4, in conjunction with shown in Fig. 2 (g) (figure obtained after SiO2 dry etching), the surface that etch step 3 is formed SiO2 exposes electrode layer TiN；When etching surface SiO2, dry etching is mainly used, electrode layer TIN is etched and stops etching.

Step 5, in conjunction with shown in Fig. 2 (h) (figure obtained after TiN wet etching), wet etching electrode layer TiN are formed Figure.Electrode layer TiN is etched, wet etching is mainly used, the silicon wafer after SiO2 is etched does removal photoresist disposition, will be without The silicon wafer of glue is put into processing in wet process slot.

In Fig. 2,2 be SiO2 (silica), and 3 be TiN (titanium nitride), and 4 be amorphous silicon, and 6 indicate photoresist.Fig. 2 (a)~ It (c) is existing MEMS electrode microbridge forming method flow diagram, wherein Fig. 2 (a) indicates to have the silicon wafer of TIN film, figure 2 (b) indicate to smear the silicon wafer after photoresist exposure, and Fig. 2 (c) indicates the figure obtained after TiN wet etching.

Above by specific embodiment, invention is explained in detail, but these are not constituted to of the invention Limitation.Without departing from the principles of the present invention, those skilled in the art can also make many modification and improvement, these It should be regarded as protection scope of the present invention.

Claims

1. a kind of MEMS electrode microbridge forming method, which comprises the steps of:

Step 1 prepares a silicon substrate, and band sacrificial layer amorphous silicon membrane is formed on the silicon substrate, is covered on the amorphous silicon membrane Cover SiO2；

Step 5, wet etching electrode layer TiN form figure.

2. the method as described in claim 1, it is characterised in that: sacrificial layer amorphous silicon membrane described in step 1 is adopted as CVD film forming Method is formed.

3. the method as described in claim 1, it is characterised in that: electrode layer TiN described in step 3 uses the film forming side PVD CVD Method is formed, and SiO2 is formed using CVD film build method.

4. the method as described in claim 1, it is characterised in that: etching surface SiO2 described in step 4 uses dry etching, etching Electrode layer TIN stops etching out.

5. the method as described in claim 1, it is characterised in that: wet etching electrode layer TiN described in step 5 etches SiO2 Silicon wafer afterwards does removal photoresist disposition, handles being put into wet process slot without the silicon wafer of glue.