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FU XingXing ZHANG Bei KANG XiangNing XU Jun XIONG Chang & ZHANG GuoYi School of Physics State Key Laboratory for Artificial Microstructures Mesoscopic Physics Peking University Beijing China 《中国科学:信息科学(英文版)》2011,(1)
We have fabricated a series of square-lattice hole photonic crystal (2PhC) arrays simultaneously at the un-current injection region on a special sample of GaN based light emitting diode (LED) by using focus ion beam milling (FIBM). The lattice constants of the 2PhC arrays vary from 230 to 1500 nm,while the 2PhC arrays have a constant area of about 9 μm×18 μm and a fixed depth of 150±10 nm which approaches but does not penetrate the active layer. Microscopic electroluminescence images and spectral measuremen... 相似文献
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We studied silver barrier ohmic (Ni/AuGe/Ag/Au) contacts to the GaAs based HEMT structures and observed strong dependence
of the cleaning procedures on the ohmic con-tact resistance (Rc), its stability and reliability. The chemical profiles of the metal con-tacts before and after alloying were measured by
SIMS. Samples cleaned with the com-bined plasma O2 and NH4OH process exhibited excellent results:R
c ∼ 0.1–0.12 ohm-mm when alloyed in the temperature range of 440–540° C and remained stable when subjected to a 200° C and
600mA/mm stress condition for 1000 hr. 相似文献
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A. Fontserè A. Pérez-TomásM. Placidi P. Fernández-MartínezN. Baron S. ChenotY. Cordier J.C. MorenoP.M. Gammon M.R. Jennings 《Microelectronic Engineering》2011,88(10):3140-3144
In this paper two types of Al/Ti-based Ohmic contacts to Gallium Nitride (GaN) based devices are presented; ImplantedN+GaN (like the ones found in the Source/Drain of GaN Metal Oxide Semiconductor Field Effect Transistors-MOSFET) and heterojunction (HJ) AlGaN/GaN contacts (Source/Drain of High Electron Mobility Transistors-HEMT). Sheet resistance (Rsh) and contact resistance (Rc) have been investigated in the temperature (T) range of 25-250 °C. It was found that the Rsh (850/700 Ω□) (25/250 °C) and Rc (2.2/0.7 Ωmm) decrease with T for ImplantedN+GaN contact and Rsh (400/850 Ω□) and Rc (0.2/0.4 Ωmm) (weakly for Rc) increase with T for HJAlGaN/GaN contact. Numerical computation based models are used to determine the theoretical Rsh and Rc behavior with T and to fit the experimental values. 相似文献
77.
Feng Liang Jing Yang Degang Zhao Zongshun Liu Jianjun Zhu Ping Chen Desheng Jiang Yongsheng Shi Hai Wang Lihong Duan Liqun Zhang Hui Yang 《半导体学报》2019,40(2):022801-022801-4
GaN-based continuous-wave operated blue-violet laser diodes (LDs) with long lifetime are demonstrated, which are grown on a c-plane GaN substrate by metal organic chemical vapor deposition with a 10 × 600 μm2 ridge waveguide structure. The electrical and optical characteristics of a blue-violet LD are investigated under direct-current injection at room temperature (25 °C). The stimulated emission wavelength and peak optical power of the LD are around 413 nm and over 600 mW, respectively. In addition, the threshold current density and voltage are as small as 1.46 kA/cm2 and 4.1 V, respectively. Moreover, the lifetime is longer than 1000 hours under room-temperature continuous-wave operation. 相似文献
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Yang Hui Chen Lianghui Zhang Shuming Chong Ming Zhu Jianjun Zhao Degang Ye Xiaojun Li Deyao Liu Zongshun Duan Lihong .. 《半导体学报》2005,26(2):414-417
Studies on first GaN-based blue-violet laser diodes(LDs) in China mainland are reported.High quality GaN materials as well as GaN-based quantum wells laser structures are grown by metal-organic chemical vapor deposition method.The X-ray double-crystal diffraction rocking curve measurements show the fullwidth half maximum of 180″ and 185″ for (0002) symmetric reflection and (10-12) skew reflection,respectively.A room temperature mobility of 850cm2/(V·s) is obtained for a 3μm thick GaN film.Gain guided and ridge geometry waveguide laser diodes are fabricated with cleaved facet mirrors at room temperature under pulse current injection.The lasing wavelength is 405.9nm.A threshold current density of 5kA/cm2 and an output light power over 100mW are obtained for ridge geometry waveguide laser diodes. 相似文献
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