The characteristics of nitrogen implanted GaAs

• Main Authors: May-May Huang, 黃郁媄
• Other Authors: Jenn-Fang Chen
• Format: Others
• Language: zh-TW
• Online Access: http://ndltd.ncl.edu.tw/handle/61071936712347306992

碩士 === 國立交通大學 === 電子物理系 === 87 === LEC(Liquid Encapsulated Czochralski) and semi-insulating GaAs(100) wafers are implanted at the room temperature with 160 keV N+ to a fluence of cm-2. Rapid thermal annealing is performed at 950℃ for 30 seconds while furnace annealing is used below 700℃ for 30 minutes. After annealing at as high as 950℃, N shows no measurable redistribution by secondary ion mass spectrometry. From X-ray diffraction, it is found that the annealing temperature up to 500℃ is necessary for the crystalline regrowth. Electrical characteristics of the material are investigated in details. From temperature-dependent conductance measurement, the carrier transport for as-implanted sample is identified to be variable-range hopping. The samples annealed above 500℃ become highly resistive. By current-voltage, admittance spectroscopy, and deep level transient spectroscopy measurements, it is found that the high-resistive material shows the characteristic of a space-charge-limited current conduction governed by traps. The activation energy of the material resistance is found to increase with increasing annealing temperature. Admittance spectroscopy displays that the activation energy of material resistance for as-implanted sample is 0.20eV which increases to 0.34, 0.59, and to 0.71eV after annealing at 500℃, 700℃, and 950℃, respectively.