INDIUM SOLDERING FOR A MOEMS BASED SAFETY AND ARMING DEVICE

摘要

A MicroOptoElectroMechanicalSystem (MOEMS) based Safety and Arming (S&A) device is being developed for the next generation of Navy torpedoes. MEMS is one of the enabling technologies for the development of smaller torpedo weapons in the future. By reducing the S&A volume by an order of magnitude, MEMS technology provides one of the means necessary to reduce the diameter of torpedoes to between one half to one third of previous systems. Reliable and robust packaging of the MEMS S&A chip is essential to ensure S&A survivability and long shelf life. The heart of the MOEMS-based S&A is a high aspect ratio MEMS chip fabricated using deep reactive ion etching (DRIE) on silicon on insulator (SOI) substrates. The S&A chip includes environmental sensors, actuators, and optical components. The device directly actuates optical fibers to shutter the firing energy for the explosive train from an out-of-line position (safe) to an in-line position (armed). The chip is housed in a hermetic, organic free clamshell package to provide reliable functionality over its 20-year life. This paper presents a brief background of the MEMS S&A program and details the associated packaging research with a specific focus on indium soldering for the formation of the hermetically sealed package with optical fiber I/O.