Differential capacitance measurements of relaxation-induced defects in InGaAs/GaAs Schottky diodes

Author

Jenn-Fang Chen ; Nie-Chuan Chen ; Wang, Jiin-Shung ; Chen, Nie-Chuan

Author_Institution

Dept. of Electrophys., Nat. Chiao Tung Univ., Hsinchu, Taiwan

Volume

48

Issue

2

fYear

2001

fDate

2/1/2001 12:00:00 AM

Firstpage

204

Lastpage

209

Abstract

The use of a differential capacitance technique for characterizing the relaxation-induced defect states in Schottky diodes has been studied. Based on a proposed equivalent circuit including the effect of potential drop across the carrier-depletion layer, a simple equation of capacitance at different voltages and frequencies is derived and compared with experimental data obtained from relaxed In_0.2Ga _0.8As/GaAs samples. It is shown that the carrier-depletion layer will introduce capacitance dispersion over frequency like traps; from it the device´s geometric parameters, the resistance of the carrier-depletion layer and the ionization energy of the deep level that gives rise to this resistance can be obtained. The relation between the low-frequency capacitance and reverse voltage can be explained well by the depletion of the free carriers between the Schottky depletion and the carrier-depletion layer. The relaxation-induced traps are believed to be at 0.535 and 0.36 eV, respectively, in the GaAs and In_0.2Ga_0.8As regions

Keywords

III-V semiconductors; Schottky diodes; capacitance; deep levels; defect states; equivalent circuits; gallium arsenide; indium compounds; semiconductor device measurement; semiconductor device models; In_0.2Ga_0.8As-GaAs; InGaAs/GaAs Schottky diodes; Schottky depletion; capacitance dispersion; carrier-depletion layer; deep level; differential capacitance measurements; equivalent circuit; free carriers depletion; geometric parameters; ionization energy; layer resistance; low-frequency capacitance; potential drop; relaxation-induced defects; relaxation-induced traps; reverse voltage; Capacitance measurement; Differential equations; Equivalent circuits; Frequency; Gallium arsenide; Indium gallium arsenide; Ionization; Schottky diodes; Spectroscopy; Voltage;

fLanguage

English

Journal_Title

Electron Devices, IEEE Transactions on

Publisher

ieee

ISSN

0018-9383

Type

jour

DOI

10.1109/16.902717

Filename

902717