Characterization of crystal structure features of a SIMOX substrate

The SIMOX commercial sample (Ibis corp.) was investigated by a high-resolution X-ray diffraction (HRXRD), a high-resolution transmission electron microscopy (HRTEM) and an Auger electron spectroscopy (AES) to determine its actual parameters (the thickness of the top Si and a continuous buried oxide layer (BOX), the crystalline quality of the top Si layer). Under used implantation conditions, the thickness of the top Si and BOX layers was 200nm and 400nm correspondingly. XRD intensity distribution near Si(004) reciprocal lattice point was investigated. According to the oscillation period of the diffraction reflection curve defined thickness of the overtop silicon layer (220±2)nm. HRTEM determined the thickness of the oxide layer (360nm) and revealed the presence of Si islands with a thickness of 30–40nm and a length from 30 to 100nm in the BOX layer nearby “BOX-Si substrate” interface. The Si islands are faceted by (111) and (001) faces. No defects were revealed in these islands. The signal from Si, which corresponds to the particles in an amorphous BOX matrix, was revealed by AES in the depth profiles. Amount of Si single crystal phase at the depth, where the particles are deposited, is about 10–20%.