MICROMACHINED SILICON CANTILEVER BEAMS FOR THIN-FILM STRESS MEASUREMENT

We present a technique for micromachining silicon cantilever beams for thin-him stress measurement. The silicon microbeams were fabricated u sing a two-step etch process with potassium hydroxide (KOH) as the ani sotropic etchant. The final beam geometry is optimized by using a 45% KOH solution and double-side polished silicon wafers as the starting m aterial. We demonstrate a cleaning procedure that produces clean micro beam surfaces as verified by Auger electron spectroscopy. The effects of KOH concentration and temperature on the etch rate, etch rate sensi tivity, and silicon surface roughness is discussed. We present results of compressive stress in boron nitride films grown by an ion-assisted process.