In-situ optical monitoring of silicon membrane etching

Franck Chollet; Ooi Giap Hwai

doi:10.1117/12.638894

28 December 2005 In-situ optical monitoring of silicon membrane etching

Franck Chollet, Ooi Giap Hwai

Proceedings Volume 6037, Device and Process Technologies for Microelectronics, MEMS, and Photonics IV; 60370B (2005) https://doi.org/10.1117/12.638894
Event: Microelectronics, MEMS, and Nanotechnology, 2005, Brisbane, Australia

Abstract

We present a simple yet efficient technique to obtain membrane with precise thickness by the etching of silicon in anisotropic etchant. This technique uses a mechanical holder to protect the front side of the wafer and a light signal to monitor from a distance the thickness of a reference hole in the etched wafer. The original feature in our set-up is that we measure the absorption of the light in two different bands of wavelength, one where the silicon is highly absorbant and the other where it is not, to improve the robustness of the measurement. This principle allows for effectively compensating for the fluctuation in the light source intensity, and provide real-time information on the membrane thickness, removing the incertitude inherent in the usual timed etch. We present the application of this technique to the manufacturing of thick single-crystal stiffener used to prevent the warp of stacked thin films presenting a gradient of stress.

Citation Download Citation

Franck Chollet and Ooi Giap Hwai "In-situ optical monitoring of silicon membrane etching", Proc. SPIE 6037, Device and Process Technologies for Microelectronics, MEMS, and Photonics IV, 60370B (28 December 2005); https://doi.org/10.1117/12.638894

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