Impact ionization in Ga1−xAlxSb

Abstract

We have measured impact ionization rates in Ga1−xAlxSb at x=0 and 0.08. For these Al contents, the ratio values of the spin-orbit splitting energy Δ to the energy gap Eg are, respectively, greater and lower than unity. We have determined that the ratio of the ionization coefficients kp/kn is greater than unity for both compositions and that it is much lower (kp/kn≊2) than the value (≳10) determined on our layers for x=0.04. Multiplication noise measurements confirm these results. The comparison to other published data show that the ionization in these antimonide compounds is not yet elucidated.

Carrier Transport Properties

“…Zhingarev et al [87] also measured a, b and their ratio for Al x Ga 1Àx Sb (x ¼ 0À0.23). More recently, Gouskov et al [89] studied the impact ionization phenomena in Al x Ga 1Àx Sb at x ¼ 0, 0.04 and 0.08 and obtained a maximum b/a at x ¼ 0.04. The b/a ratio obtained by Kuwatsuka et al was $5 at the low electric field of 1.6 Â 10 5 V/cm.…”

Near infrared avalanche photodiodes with bulk Al0.04Ga0.96Sb and GaSb/AlSb superlattice gain layers

“…To date, there has been a number of studies on AlGaSb avalanche photodiodes, all of which have relied on liquid phase epitaxy ͑LPE͒ as the crystal growth method, [3][4][5] and focused on noise reduction from hole impact ionization enhancement when the spin-orbit split-off band difference ⌬ matched the band gap E g in bulk AlGaSb. The results of these studies indicate a lack of consensus about the resonant hole ionization effect.…”