[18p-N302-1~18] 13.7 Compound and power electron devices and process technology

△ [18p-N302-15] Quick measurement method for carbon-related defect density in n-type GaN layer by dual-color-sub-bandgap-light-excited isothermal capacitance transient spectroscopy

〇Kazutaka Kanegae^1,4, Tetsuo Narita², Kazuyoshi Tomita², Tetsu Kachi³, Masahiro Horita^1,3,4, Tsunenobu Kimoto¹, Jun Suda^1,3,4 (1.Kyoto Univ., 2.Toyota Central R&D Labs., 3.Nagoya Univ. IMaSS, 4.Nagoya Univ.)

Keywords:GaN, Carbon, deep level

We propose a quick measurement method of the carbon-related hole trap (H1, E_V+0.87 eV) density in n-type GaN by dual-color-sub-bandgap-light-excited iso-thermal capacitance transient spectroscopy. Shorter wavelength light irradiation is carried out to make the hole trap to be hole-occupied state. Then, longer wavelength light irradiation is carried out to emit the hole from the trap to the valence band. The trap density can be calculated from the capacitance change. Because the hole photoexcitation rate is mucher then hole thermal emission rate, this measurement method reduces the measurement time to less than one tenth. The quick measurement method is useful for the wafer mapping measurement of the H1 trap density.