Suppression of plasma-induced fluorine damage in P-HEMTs using strained InSb barrier

Abstract

We propose a P-HEMT structure with a strained InSb barrier inserted and investigate its resistivity against plasma-induced fluorine damage with Hall measurements and a SIMS evaluation. The fluorine intrusion into the active layers of the P-HEMT during the RIE process was greatly suppressed by the ultra thin InSb barrier layer and the values of the carrier density and electron mobility improved by 43% and 35% from those for a conventional P-HEMT. After thermal annealing, the number of accumulated fluorine atoms in the δ-doped layer also decreased and the carrier density and electron mobility improved by 36% and 11% from those for a conventional P-HEMT. This indicated the strained InSb barrier was very effective in suppressing the plasma-induced fluorine damage in the P-HEMT.