Sub-bandgap refractive indexes and optical properties of Sidopedβ-Ga_(2)O_(3) semiconductor thin films  

作　　者：Yitian Bao Xiaorui Wang Shijie Xu 

机构地区：[1]Department of Physics,The University of Hong Kong,Pokfulam Road,Hong Kong,China 2Department of Optical Science and Engineering,School of Information Science and Technology,Fudan University,Shanghai 200438,China

出　　处：《Journal of Semiconductors》2022年第6期46-50,共5页半导体学报（英文版）

基　　金：This study was financially supported by the National Natural Science Foundation of China(No.12074324);the Shenzhen Municipal Science and Technology Innovation Council(No.JCJY20180508163404043).

摘　　要：In this article,we present a theoretical study on the sub-bandgap refractive indexes and optical properties of Sidopedβ-Ga_(2)O_(3) thin films based on newly developed models.The measured sub-bandgap refractive indexes ofβ-Ga_(2)O_(3) thin film are explained well with the new model,leading to the determination of an explicit analytical dispersion of refractive indexes for photon energy below an effective optical bandgap energy of 4.952 eV for theβ-Ga_(2)O_(3) thin film.Then,the oscillatory structures in long wavelength regions in experimental transmission spectra of Si-dopedβ-Ga_(2)O_(3) thin films with different Si doping concentrations are quantitively interpreted utilizing the determined sub-bandgap refractive index dispersion.Meanwhile,effective optical bandgap values of Si-dopedβ-Ga_(2)O_(3) thin films are further determined and are found to decrease with increasing the Si doping concentration as expectedly.In addition,the sub-bandgap absorption coefficients of Si-dopedβ-Ga_(2)O_(3) thin film are calculated under the frame of the Franz–Keldysh mechanism due to the electric field effect of ionized Si impurities.The theoretical absorption coefficients agree with the available experimental data.These key parameters obtained in the present study may enrich the present understanding of the sub-bandgap refractive indexes and optical properties of impurity-dopedβ-Ga_(2)O_(3) thin films.

关 键 词：gallium oxide sub-bandgap refractive index Si doping effective optical bandgap sub-bandgap absorption 

分 类 号：TN304.055[电子电信—物理电子学]