Applications of UV–Raman spectroscopy and high-resolution X-ray diffraction to microelectronic materials and devices

Abstract

Raman spectroscopy (RS) and high-resolution X-ray diffraction (HRXRD) are two powerful non-destructive techniques commonly used to characterize micro-electronic materials and device structures. In the case of visible Raman spectroscopy, the technique is severely limited in both lateral and depth resolution in applications to rapidly shrinking ULSI device structures. The UV micro-Raman technique can greatly enhance the spatial resolution by taking advantage of the shorter wavelength and much smaller optical penetration depth (<10 nm in Si at 325 nm versus 400 nm in the visible). We present UV micro-Raman mapping of stress and crystallinity in shallow trench isolated (STI) CMOS devices. Additionally, we show how UV micro-Raman and HRXRD techniques are used to characterize strain, composition, and relaxation in ultra-thin strained Si channels on SiGe buffers.