Effective MEMS Manufacturing Using Vapor HF Etch Processing Illustrated by Means of a Sterilization Cycle Counter

Abstract:
In the aftermath of COVID-19 and with an increased awareness of health issues, the use of precisely targeted technological methodologies for the solution of specific healthcare problems is becoming increasing important in medical applications. The use of MEMS technology for the development of an efficient sterilisation cycle counter by Hahn-Schickard is a simple but very effective example of such an application. Surface micromachining is applied utilizing vapor HF (vHF) etching and subsequent polymer anti-stiction coating as an efficient technique to remove sacrificial buried oxide layers and to release micro structure without stiction. The vHF etching process has been optimized and reaches etch rates of 900 nm/min for the buried oxide with a uniformity of more than 95 % across a 100 mm wafer.