CN101439842A

CN101439842A - Method for manufacturing micro-mechanical cantilever beam array with substrate silicon as fixing column

Info

Publication number: CN101439842A
Application number: CNA200710177792XA
Authority: CN
Inventors: 石莎莉; 陈大鹏; 景玉鹏; 欧毅; 叶甜春
Original assignee: Institute of Microelectronics of CAS
Current assignee: Institute of Microelectronics of CAS
Priority date: 2007-11-21
Filing date: 2007-11-21
Publication date: 2009-05-27

Abstract

The invention discloses a method for producing a micromechanical cantilever array taking substrate silicon as a clamping support, which comprises the following steps: a <100> silicon substrate is double-sidedly deposited with SiNx thin films; the surface lithography is performed, wherein the SiNx thin films are etched to form corrosion windows, and a photoresist is removed; the silicon substrate is corroded to form a square cantilever array with a substrate silicon clamping column at the center; and the frontal lithography is performed, wherein the SiNx thin films are etched, and the photoresist is removed to form a rectangular cantilever array with single-point clamped supporting, symmetry and high length-width ratio, or form a rectangular cantilever array clamped at one end. The utilization of the method simplifies a production process and can adapt to the requirement of mass production.

Description

The preparation method of the micromachine cantilever beam array that props up based on substrate silicon as fixing

Technical field

The present invention relates to micromechanics (MEMS) the manufacturing technology field in the microelectric technique, relate in particular to a kind of preparation method of the micromachine cantilever beam array that props up based on substrate silicon as fixing.

Background technology

In the MEMS manufacturing technology, the silicon substrate surface micromachining technology is an important component part, has avoided body silicon deep processing longitudinally, with integrated circuit technology better compatibility is arranged, and helps the integrated of structural devices and treatment circuit.

In silicon substrate surface micromachined process, " sacrifice layer " technology that apply to is made unsettled beam, film or cavity structure, promptly finishes by the step of sacrifice layer deposition, etching, the solid pillar of deposit and structure sheaf film.

Many weeks, this method comprises multistep technology, and is loaded down with trivial details consuming time, the requirement of incompatibility large-scale production.

Summary of the invention

(1) technical problem that will solve

In view of this, main purpose of the present invention is to provide a kind of preparation method of the micromachine cantilever beam array that props up based on substrate silicon as fixing, to simplify manufacture craft, adapts to the requirement of large-scale production.

(2) technical scheme

For achieving the above object, the invention provides a kind of preparation method of the micromachine cantilever beam array that props up based on substrate silicon as fixing, this method comprises:

＜100〉two-sided deposit SiN on the silicon substrate _XFilm;

Photomask surface, etching SiN _XFilm forms corrosion window, removes photoresist;

The corrosion silicon substrate forms the center band substrate silicon square cantilever array of pillar admittedly;

Positive photoetching, etching SiN _XFilm removes photoresist, and forms that single-point props up admittedly, the rectangle cantilever array of symmetric form, high-aspect-ratio, perhaps forms solid rectangle cantilever array at one end.

In the such scheme, described＜100〉two-sided deposit SiN on the silicon chip _XIn the step of film, adopt the LPCVD method to carry out deposit.

In the such scheme, in the described photomask surface step, adopt SF ₆Gas, flow and 60 to 70w power isotropic etching SiN with 60 to 70sccm _XFilm forms corrosion window till the silicon substrate.

In the such scheme, in the described corrosion silicon substrate step, adopting proportioning is 9 to 10 milliliter 40% HF solution, 72 to 75 milliliter 67% HNO ₃The HC of solution and 38 to 40 milliliter 99% ₂H ₃O ₂Solution adopts isotropic etch method corrosion silicon under 12 to 15 ℃ of conditions of room temperature, form silicon wedge shape support column.

In the such scheme, in the lithography step of described front, adopt SF ₆Gas, the flow with 60 to 70sccm and 60 to 70w power isotropic etching SiNx film form that single-point props up admittedly, the rectangle cantilever array of symmetric form, high-aspect-ratio till the silicon substrate, perhaps form solid rectangle cantilever array at one end.

(3) beneficial effect

From technique scheme as can be seen, the preparation method of this micromachine cantilever beam array that props up based on substrate silicon as fixing that the invention provides, utilize the isotropic etch of silicon substrate in corrosive liquid to go out the solid pillar of silicon, sacrifice layer process has been avoided in the making of the solid pillar of this silicon, comprise the sacrifice layer deposition, etching, the step of the solid pillar of deposit, and directly utilize silicon substrate isotropic etch in corrosive liquid to go out the solid pillar of silicon, the formation of its solid pillar with by in sacrifice layer etching, the solid pillar that deposit goes out is compared, with substrate more firm being connected arranged, so stronger impact resistance is arranged; Simultaneously, the cantilever beam film that this method forms is at first deposition formation before solid pillar forms, compare with the cantilever beam film that on sacrifice layer, forms, avoided the processing step of in the sacrifice layer etched hole, filling, so it is more smooth, even, simplify manufacture craft, can adapt to the requirement of large-scale production.

In addition, this method is with low cost, the production efficiency height, and process stabilizing has very strong practical value; And this method can obtain to prevent the sacrifice layer of adhesion, is suitable for large-scale production.

Description of drawings

The present invention is further described below in conjunction with drawings and Examples:

The method flow diagram of Fig. 1 micromachine cantilever beam array that to be making provided by the invention prop up based on substrate silicon as fixing;

Fig. 2 to Fig. 5 is a process chart of making the micromachine cantilever beam array that props up based on substrate silicon as fixing according to the embodiment of the invention;

Wherein, Fig. 3 a, 4a and 5a are profile, and Fig. 3 b, 4b and 5b are vertical view.

The specific embodiment

For making the purpose, technical solutions and advantages of the present invention clearer, below in conjunction with specific embodiment, and with reference to accompanying drawing, the present invention is described in more detail.

As shown in Figure 1, the method flow diagram of Fig. 1 micromachine cantilever beam array that to be making provided by the invention prop up based on substrate silicon as fixing, this method comprises:

Step 101:＜100〉two-sided deposit SiN on the silicon substrate _XFilm; In this step, adopt the LPCVD method to carry out deposit.

Step 102: photomask surface, etching SiN _XFilm forms corrosion window, removes photoresist; In this step, adopt SF ₆Gas, flow and 60 to 70w power isotropic etching SiN with 60 to 70sccm _XFilm forms corrosion window till the silicon substrate.

Step 103: the corrosion silicon substrate forms the center band substrate silicon square cantilever array of pillar admittedly; In this step, adopting proportioning is 9 to 10 milliliter 40% HF solution, 72 to 75 milliliter 67% HNO ₃The HC of solution and 38 to 40 milliliter 99% ₂H ₃O ₂Solution adopts isotropic etch method corrosion silicon under 12 to 15 ℃ of conditions of room temperature, form silicon wedge shape support column.

Step 104: positive photoetching, etching SiN _XFilm removes photoresist, and forms that single-point props up admittedly, the rectangle cantilever array of symmetric form, high-aspect-ratio, perhaps forms solid rectangle cantilever array at one end; In this step, adopt SF ₆Gas, the flow with 60 to 70sccm and 60 to 70w power isotropic etching SiNx film form that single-point props up admittedly, the rectangle cantilever array of symmetric form, high-aspect-ratio till the silicon substrate, perhaps form solid rectangle cantilever array at one end.

The method flow diagram of the micromachine cantilever beam array that props up based on substrate silicon as fixing based on making shown in Figure 1, Fig. 2 to Fig. 5 shows the process chart of making the micromachine cantilever beam array that props up based on substrate silicon as fixing according to the embodiment of the invention, specifically may further comprise the steps:

As shown in Figure 2,＜100〉LPCVD SiN on the silicon chip 101 _X Film 102, thickness are 0.1 to 0.2 μ m; The dark SiN of isotropic etching 0.1 to 0.2 μ m _X Film 102 corrosion windows;

As shown in Figure 3, adopting proportioning is 9 to 10ml 40% HF solution, 72 to 75ml 67% HNO ₃Solution and 38 to 40ml 99% HC ₂H ₃O ₂Solution, corrosion silicon 2 to 3 μ m under room temperature (12 to 15 ℃) condition form solid pillar 103 of silicon and square cantilever 104;

As shown in Figure 4, use SF ₆Gas, flow and 60 to 70w power isotropic etching SiN with 60 to 70sccm _XFilm forms that single-point props up admittedly, the rectangle cantilever array 105 of symmetric form, high-aspect-ratio;

As shown in Figure 5, use SF ₆Gas, flow and 60 to 70w power isotropic etching SiN with 60 to 70sccm _XFilm forms solid rectangle cantilever array 106 at one end.

Above-described specific embodiment; purpose of the present invention, technical scheme and beneficial effect are further described; institute is understood that; the above only is specific embodiments of the invention; be not limited to the present invention; within the spirit and principles in the present invention all, any modification of being made, be equal to replacement, improvement etc., all should be included within protection scope of the present invention.

Claims

1, a kind of preparation method of the micromachine cantilever beam array that props up based on substrate silicon as fixing is characterized in that this method comprises:

＜100〉two-sided deposit SiN on the silicon substrate _xFilm;

2, the preparation method of the micromachine cantilever beam array that props up based on substrate silicon as fixing according to claim 1 is characterized in that, and is described＜100〉two-sided deposit SiN on the silicon chip _xIn the step of film, adopt the LPCVD method to carry out deposit.

3, the preparation method of the micromachine cantilever beam array that props up based on substrate silicon as fixing according to claim 1 is characterized in that, in the described photomask surface step, adopts SF ₆Gas, flow and 60 to 70w power isotropic etching SiN with 60 to 70sccm _xFilm forms corrosion window till the silicon substrate.

4, the preparation method of the micromachine cantilever beam array that props up based on substrate silicon as fixing according to claim 1 is characterized in that, in the described corrosion silicon substrate step, adopting proportioning is 9 to 10 milliliter 40% HF solution, 72 to 75 milliliter 67% HNO ₃The HC of solution and 38 to 40 milliliter 99% ₂H ₃O ₂Solution adopts isotropic etch method corrosion silicon under 12 to 15 ℃ of conditions of room temperature, form silicon wedge shape support column.

5, the preparation method of the micromachine cantilever beam array that props up based on substrate silicon as fixing according to claim 1 is characterized in that, in the lithography step of described front, adopts SF ₆Gas, flow and 60 to 70w power isotropic etching SiN with 60 to 70sccm _xFilm forms that single-point props up admittedly, the rectangle cantilever array of symmetric form, high-aspect-ratio till the silicon substrate, perhaps forms solid rectangle cantilever array at one end.