Stress analysis of a standard CMOS process

Ulrich Munch; V. Ziebart; Henry Baltes; Oliver Paul; Elko Doering

doi:10.1117/12.364460

29 September 1999 Stress analysis of a standard CMOS process

Ulrich Munch, V. Ziebart, Henry Baltes, Oliver Paul, Elko Doering

Proceedings Volume 3891, Electronics and Structures for MEMS; (1999) https://doi.org/10.1117/12.364460
Event: Asia Pacific Symposium on Microelectronics and MEMS, 1999, Gold Coast, Australia

Abstract

Thin film stress has turned out to be a limiting factor for the fabrication of dielectric membrane based microsystem using commercial CMOS processes. Due to the compressive stress in the CMOS dielectrics, membranes tend to buckle and - in the extreme case - to break, i.e., the sensor yield is reduced and consequently production costs rise. In this paper we report the results of the stress analysis of a commercial 1 micrometers , single poly, double metal CMOS process. All dielectric layers from the field oxide to the passivation were analyzed. We investigate several methods to taylor the stresses in the dielectrics to the needs of microsensor fabrication. The most mature method was to change the stress in the passivation layer by adjusting the deposition parameters. We investigated two passivation layers in more detail. With the standard passivation the dielectric sandwich has a total thickness of nearly 4 micrometers and an average stress of -162 MPa. The second passivation layer is thicker and more tensile than the standard passivation. It reduces the average stress to -15 MPa. The critical buckling lengths of CMOS dielectric membranes were determined experimentally. We found the critical buckling lengths of such membranes containing these two passivation layers to be (194 + 26) micrometers and (967 + 103) micrometers , respectively.

Citation Download Citation

Ulrich Munch, V. Ziebart, Henry Baltes, Oliver Paul, and Elko Doering "Stress analysis of a standard CMOS process", Proc. SPIE 3891, Electronics and Structures for MEMS, (29 September 1999); https://doi.org/10.1117/12.364460

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available