Carrier Concentration Dependence of Photoacoustic Spectra of Silicon by a Piezoelectric Transducer Method

Abstract

We report the current-induced light emission (CILE) at RT from a porous silicon (PS) Schottky device exhibiting good rectifying characteristics with the ideal factor of 14. The photoluminescence spectrum from the PS layer fabricated by laterally anodization peaks at 688nm. The intensity of CILE increases with increasing current. It has run for more than two hours and still keeps stable. Possible mechanism of CILE is discussed.

Optical Characterization of High Quality ZnTe Substrate

“…We do not have enough data to discuss this here. However, Kuwahata et al [15] report that the PPT signal intensity at energies slightly higher than the E g decrease for n-type and increase for p-type Si with increasing carrier concentration. The decrease and increase are considered to be due to the increase of free electrons at the bottom of the conduction band and to the increase of holes at the top of the valence band, respectively.…”

Carrier lifetime influence on clamped silicon wafer resonance by PTA effect

“…Carrier thermalization and bulk recombination process generate electronic strain with specific frequency dependences and thermal diffusion process has also to be taken into account to study photo-acoustic efficiency [4,5]. From all these mechanisms, carrier transport characteristics of semiconductors have been studied using gas-microphone photo-acoustic cell [5][6][7], beam deflection [4] or piezoelectric detection [8]. Imaging of doping regions in silicon has been also obtained by scanning electron acoustic microscopy [9,10].…”

“…The photo-acoustic efficiency of our clamped system could be improved by the correct choice of the membrane size and doping. For Silicon, the best efficiency of the PTA effect is obtained for wavelength around 800nm [7].…”