By Topic

A diffusion/chemical reaction model for HE etching of LPCVD phosphosilicate glass sacrificial layers

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$33 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

3 Author(s)
D. J. Monk ; Dept. of Chem. Eng., California Univ., Berkeley, CA, USA ; D. S. Soane ; R. T. Howe

The authors deal with the etching of LPCVD phosphosilicate glass (PSG) sacrificial layers by solutions of hydrofluoric acid (HF). A diffusion/chemical reaction model has been derived assuming one-component steady-state diffusion, one-dimensional geometry, no effect of heat of reaction, and a constant diffusion coefficient. The model fits the experimental data successfully with physically reasonable diffusion coefficients for concentrated HF solutions (3-5*10/sup -5/ cm/sup 2//s). The chemical reaction kinetics have been described experimentally with a non-first order reaction rate expression. Experimental studies using an etching test structure are reported for the effect of channel width, the use of low-stress nitride and polysilicon as the channel structural material, several etchants (including: HF, BHF and surfactant HF), and external agitation. The oxide etch process shifts from reaction-controlled to diffusion-controlled as the etch channel develops.<>

Published in:

Solid-State Sensor and Actuator Workshop, 1992. 5th Technical Digest., IEEE

Date of Conference:

22-25 June 1992