Threshold field for soft damage and electron drift velocity in InGaN two-dimensional channels

Experimental investigation of electron transport along a two-dimensional channel confined in an InGaN alloy of AlInN/AlN/InGaN/GaN structure was performed at room temperature under near-equilibrium thermal-bath temperature. A soft damage was observed at a threshold electric field applied in the channel plane. The threshold current for soft damage and the supplied electric power were lower in the channels with a higher electron density. The results are interpreted in terms of plasmon-assisted heat dissipation. In agreement with ultra-fast decay of hot phonons in the vicinity of the resonance with plasmons, the electron drift velocity acquires a highest value of ~2 × 107 cm s−1 at 180 kV cm−1 in channels with 1 × 1013 cm−2 and decreases as the electron density increases. No negative differential resistance is observed. The effective hot-phonon lifetime is estimated as ~ 2 ps at 1.6 × 1013 cm−2 at low electric fields and is found to decrease as the field increases.