Field Assisted Etching,
ROYAL SIGNALS AND RADAR ESTABLISHMENT MALVERN (ENGLAND)
Pagination or Media Count:
We have investigated the effects of both high gravitational and electric fields on wet etching with the objective of inducing anisotropy in otherwise isotropic etch systems and of removing particulates. Although we achieved anisotropy when etching silicon in HNA and gallium arsenide in a phosphoricsulphuricperoxide etch in a high gravitational field, the results depended on the size and depth of the features, so we do not believe that this will be useful in standard semiconductor processing. The use of a large gravitational field did result in the removal of a substantial fraction of the particulates which are formed when etching aluminumsiliconcopper, and this may be technologically useful. We also found that the use of large gravitational fields was an effective tool for the identification of diffusion limited etch systems. The application of a high electric field to a prototype non-conducting etch system modified the etching and this effect could merit further investigation.
- Solid State Physics