Method to determine the quality of sapphire

Semiconductor measurement technology

“…The quality of each surface was expressed as the ratio of the reflected intensity at wavenumber 600 cm~-^to that of wavenumber 450 cm~l [55].…”

“…neutron activation analysis [26][27] nuclear-track technique [36][37] numerical aperture, optical microscope [42][43][44] optical image profiles [42][43][44] optical microscope focus [42][43][44] optical test for surface quality [37][38][39] oxide hygrometer sensor [49][50][51] particle-impact noise detection (FIND) resolution, scanning acoustic microscope [55][56][57] safe-operating-area (SOA) limit, transistor 57-59 sapphire substrates [37][38][39]; see also silicon on sapphire scanning acoustic microscopy [54][55][56][57] scanning low-energy electron probe (SLEEP) 33-34 second breakdown [57][58][59] secondary-ion mass spectroscopy (SIMS) 33 silicon on sapphire (SOS) 24-25; 27; 37-39; 48; 54 spreading resistance methods [7][8][9][10][11][12][13][14][15][16][17] spu...…”

Raman-based metrology of thin film systems

“…Once an epitaxial silicon layer has been grown and recrystallized, or a silicon layer bonded to the sapphire wafer, standard semiconductor fabrication processes can be utilized to fabricate CMOS devices and integrated circuits [44,47,48]. At each stage in the SPER process, as well as in the further processing of SOS devices, it may be necessary to check the thickness of the various material layers to ensure that process conditions are as expected.…”