Fig. 1. Schematic diagram of a defect location in an InP-based HEMT

Fig. 2. Electron concentration and mobility as a function of electron fluence^[32]

Fig. 3. Surface morphology of InAlAs/InGaAs heterostructure measured using AFM(a) Before electron irradiation, (b) After electron irradiation (3 µm×3 µm)^[22]

Fig. 4. Electrical characteristics of InP-based HEMTs with different proton fluences (color online)(a) Channel current, (b) Current gain cutoff frequency^[18]

Fig. 5. Changes of f_T and f_max of InP-based HEMTs before and after 1 MeV electron irradiation^[22]

Fig. 6. (a) Inverse I_G-V_G characteristics of InP-based HEMTs with different electron fluences, (b) n and Φ_B extracted from the measured I_G-V_G curves as a function of electron fluence^[23]

Fig. 7. S₂₂ of InP-based HEMTs before and after electron irradiation under different electron fluences^[51]

Fig. 8. The "peak collapse" effect of transconductance of InP-based HEMT (color online)(a) Transfer characteristics, (b) Pinch-off gate voltage, (c) Defect distribution generated by irradiation with zero gate voltage ^[27]

Fig. 9. Variations of normalized n_s (a) and normalized µ (b) with proton fluence for single and composite channels^[62]

Fig. 10. (a) Conventional structure of InP-based HEMT, (b) Double Si-doped structure of InP-based HEMT, (c) Current degradation curves of InP-based HEMT channel of conventional structure and double Si-doped structure^[66]

Fig. 11. Normalized effects of electron irradiation on the 2D electron gas concentration and electron mobility of InP HEMTs with different InGaAs channel in compositions under different temperature (a) Room temperature, (b) 77 K temperature^[67]