Manufacturing method of MEMS structures and manufacturing method of MEMS structures with semiconductor device

• US 20070249082A1
• Filed: 01/26/2007
• Published: 10/25/2007
• Est. Priority Date: 02/03/2006
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Fukuda, Hiroshi, Fujimori, Tsukasa, Hanaoka, Yuko
• Granted Patent: US 7,670,861 B2
• Time in Patent Office: Days
• US Class Current: 438/53
• CPC Class Codes: B81C 1/00246 Monolithic integration, i.e. micromechanical structure and electronic processing unit are integrated on the same substrate
• CPC Class Codes: B81C 2203/0735 Post-CMOS, i.e. forming the micromechanical structure after the CMOS circuit
• CPC Class Codes: G01L 9/0042 Constructional details associated with semiconductive diaphragm sensors, e.g. etching, or constructional details of non-semiconductive diaphragms details about the integration or bonding of piezoresistor in or on the diaphragm G01L9/0052 and G01L9/0057 respectively
• CPC Class Codes: G01L 9/0073 using a semiconductive diaphragm
• CPC Class Codes: H01L 21/32053 of metal-silicide layers

Abstract

The objects of the present invention are to form MEMS structures of which stress is controlled while maintaining the performance of high-performance LSI, to integrate MEMS Structures and LSI on a single chip, to electrically and chemically protect the MEMS structure and to reduce the stress of the whole movable part of the MEMS structure. To achieve the above objects, a silicide film formable at a low temperature is used for the MEMS structure. The temperature at the silicide film deposition T1 is selected optionally with reference the heat treatment temperature T2 and the pseudo-crystallization temperature T3. T2, the temperature of manufacturing process after the silicide film deposition, is determined does not cause the degradation of the characteristics of the high-performance LSI indispensable. Thus, the residual stress of the MEMS structures may be controlled.

Claims

1. A manufacturing method of MEMS structures with movable parts fabricated on the substrate, comprising:

a step of fabricating said movable parts by using a thin film including a high melting point silicide,

wherein the film-fabricating heat treatment temperature T1 of said thin film in said movable parts fabricating step is set within a temperature range of T1≧

350°

C., and the upper limit temperature T2 for the heat treatment temperature in the subsequent step of said movable parts fabricating step is set within a temperature range of 400°

C.≦

T2≦

450°

C. so that the stress that said thin film has in the fabricating step of said MEMS structure may be brought within a range of tensile stress of the predetermined value.

2. The manufacturing method of MEMS structures according to claim 1, wherein said predetermined value of tensile stress range is 0 Mpa to 500 MPa.

5. The manufacturing method of MEMS structures according to claim 1, wherein said movable part is a laminated film comprising an electrode film including a high-melting point metallic silicon compound and an insulation film accumulated on top of said electrode film.

6. The manufacturing method of MEMS structures according to claim 1, wherein said movable part is a laminated film comprising a shield film made of a high-melting point metal or a high-melting point silicide, an insulation film fabricated on said shield film and an electrode film made of a high-melting point metal or a high-melting point silicide fabricated on said insulation film.

7. The manufacturing method of MEMS structures according to claim 6, wherein at least either one of said shield film or said electrode film is made of a high-melting point silicide.

8. The manufacturing method of MEMS structures according to claim 6, wherein said electrode film is fabricated by W or WSi.

9. The manufacturing method of MEMS structures according to claim 6, wherein said shield film is fabricated by Ta or WSi.

10. A manufacturing method of MEMS structures with semiconductor device, comprising the steps of:

fabricating an electronic circuit on the substrate; and

fabricating MEMS structures on said substrate by the manufacturing method according to claim 1.

11. The manufacturing method of MEMS structures with semiconductor device according to claim 10,

wherein said electronic circuit has at least one of an analogue circuit, a digital circuit or a memory circuit.

12. The manufacturing method of MEMS structures with semiconductor device according to claim 10,

wherein said MEMS structure has cavities with a degree of vacuum sufficiently lower than the atmospheric pressure or cavities filled with a gas.

3. A manufacturing method of MEMS structures with movable parts fabricated on the substrate, comprising:

a step of fabricating said movable parts by using a thin film including a silicide with a high melting point;

wherein the film-fabricating heat treatment temperature T1 of said thin film in said movable parts fabricating step is set within a temperature range of T1≦

350°

C., and the upper limit temperature T2 for the heat treatment temperature in the subsequent step of said movable parts fabricating step is set within a temperature range of 400°

C.≦

T2≦

450°

C. so that the stress that said thin film has in the fabricating step of said MEMS structure may be brought within a range of tensile stress of the predetermined value.

4. The manufacturing method of MEMS structures according to claim 3, wherein said predetermined value of tensile stress range is 500 MPa to 1 GPa.

13. MEMS structures having a movable part fabricated on the substrate, wherein said movable part is fabricated by the manufacturing process comprising:

a step of fabricating said movable parts by using a thin film including a high melting point silicide,

wherein the film-fabricating heat treatment temperature T1 of said thin film in said movable parts fabricating step is set within a temperature range of T1≧

350°

C., and the upper limit temperature T2 for the heat treatment temperature in the subsequent step of said movable parts fabricating step is set within a temperature range of 400°

C.≦

T2≦

450°

C. so that the stress that said thin film has in the fabricating step of said MEMS structure may be brought within a range of tensile stress of the predetermined value.

14. The MEMS structure according claim 13,

wherein said movable part is a laminated film comprising a shield film made of a high-melting point metal or a high-melting point silicide, an insulating film fabricated on top of said shield film, and an electrode film made of a high-melting point metal or a high-melting point silicide fabricated on said insulation film.

15. The MEMS structure according claim 14, wherein at least either one of said shield film or said electrode film is made of a high-melting point metal silicone compound.

16. The MEMS structure according claim 14, wherein said electrode film is fabricated by W or WSi.

17. The MEMS structure according claim 14, wherein said shield film is fabricated by Ta or WSi.