Micromachining using ultrasonic impact grinding

Abstract

Although largely unknown in the MEMS community, micromachining using ultrasonic impact grinding (UIG) is a fascinating yet easy fabrication scheme to achieve virtually any shape, such as a shallow or deep reservoir, a channel, a via, etc, in silicon, glass and other commonly used ceramic and semiconductor materials in the MEMS field. Because of the patterning and masking issues, etching even shallow channels or vias in a pre-processed silicon/glass/ceramic substrate is somewhat difficult, if not impossible. However, by using UIG one can achieve such structures, up to millimeters in depth in virtually no time. Furthermore, in silicon substrates, the orientation or any other physical dimension of the feature will no longer be constrained as in anisotropic etching by the crystallographic planes and directions; and in amorphous glass or ceramic substrates, features with vertical walls can be achieved, otherwise usually accomplished only by expensive laser ablation. Thus, the authors believe that this UIG process could open up many avenues to easily and quickly achieve the larger MEMS structures as well as packaging for both prototype and for production in silicon, glass and ceramic.

Performance Investigation of Piezoelectric Ultrasonic Vibrator for Uniform Atomization Application

“…일 반적으로 20 kHz~200 kHz에서 작동하는 초음파 진동 자는 큰 진폭과 파워를 동시에 갖기 유리한 종방향모드 (longitudinal mode)의 진동을 이용한다. 대표적으로 Langevin이 제안한 볼트 체결형 진동자가 있으며, 가 장 일반적인 구조로서 진폭을 증대시키기 위해 혼과 연 결되는 방식을 사용한다 (4) . 이러한 초음파 진동자는 기 계적, 전기적, 열적 요소에 의해 성능이 제한되지만 압 전작동기의 고속응답성과 철이나 티타늄 등을 이용한 다양한 형태의 혼에 의한 높은 파워 밀도에 의해 다양 한 분야에서의 응용이 가능하다 (5) .…”