应变补偿BGaN/AlGaN超晶格深紫外LED空穴浓度  

Hole Concentration of Strain-compensated BGaN/AlGaN Superlattice for Deep Ultraviolet LED

作　　者：董明慧 张燕[1] 栾加航 申世英 DONG Minghui;ZHAGN Yan;LUAN Jiahang;SHEN Shiying(College of Engineering,Shandong Xiehe University,Jinan,250107,CHN)

机构地区：[1]山东协和学院工学院,济南250107

出　　处：《固体电子学研究与进展》2024年第6期603-610,共8页Research & Progress of SSE

基　　金：山东省教育厅高校“青创科技支持计划”资助项目(2023KJ294)。

摘　　要：高Al组份AlGaN薄膜中的Mg受主活化能较大、空穴浓度较低,制约了AlGaN基深紫外发光二极管(Light-emitting diode,LED)的辐射复合效率。为了提高AlGaN的空穴浓度,构筑了BGa N/AlGaN超晶格对空穴浓度进行补偿。由于应变产生了极化电场、能带弯曲,使B_(0.14)Ga_(0.86)N/Al_(0.5)Ga_(0.5)N超晶格的空穴浓度高达5.7×10^(18)cm^(-3)。与Al_(0.5)Ga_(0.5)N、Al_(0.4)Ga_(0.6)N/Al_(0.5)Ga_(0.5)N超晶格相比,B_(0.14)Ga_(0.86)N/Al_(0.5)Ga_(0.5)N超晶格的空穴有效质量小,而迁移率高,有利于空穴-电子在多量子阱区域辐射复合。由于能带弯曲和电子阻挡层能够有效阻止电子向p型区域扩散,导致B_(0.14)Ga_(0.86)N/Al_(0.5)Ga_(0.5)N超晶格的电子电流密度几乎为0,而空穴电流密度高达112.1 m A/cm^(2)。另外电子阻挡层还导致B_(0.14)Ga_(0.86)N/Al_(0.5)Ga_(0.5)N超晶格结构的内量子效率、输出功率以及自发发射光谱明显高于Al_(0.5)Ga_(0.5)N、Al_(0.4)Ga_(0.6)N/Al_(0.5)Ga_(0.5)N超晶格。综上所述,BGa N/AlGaN超晶格产生的应变能够对空穴浓度进行补偿,且改善AlGaN基深紫外LED的发光性能。The high Mg acceptor activation energy and low hole concentration in high Al component Al Ga N films restrict the radiation recombination efficiency of Al Ga N based deep ultraviolet lightemitting diodes(UV LEDs).In order to improve the hole concentration of Al Ga N,the BGa N/AlGa N superlattice is constructed to compensate the hole concentration.Due to the polarization electric field and energy band bending caused by the strain,the hole concentration of B_(0.14)Ga_(0.86)N/Al_(0.5)Ga_(0.5)N superlattice is as high as 5.7×10^(18)cm^(-3).The effective mass of holes in B_(0.14)Ga_(0.86)N/Al_(0.5)Ga_(0.5)N superlattice is smaller than that in Al_(0.5)Ga_(0.5)N and Al_(0.4)Ga_(0.6)N/Al_(0.5)Ga_(0.5)N superlattices,while the mobility is higher,which is beneficial for radiation recombination of holes and electrons in multiple quantum wells.Due to band bending and the effective electron barrier layer preventing the diffusion of electrons into the p-type region,the electron current density of the B_(0.14)Ga_(0.86)N/Al_(0.5)Ga_(0.5)N superlattice is almost zero,while the hole current density is as high as 112.1 m A/cm~2.In addition,the electron barrier layer also leads to significantly higher internal quantum efficiency,output power,and spontaneous emission spectra of the B_(0.14)Ga_(0.86)N/Al_(0.5)Ga_(0.5)N superlattice compared to the Al_(0.5)Ga_(0.5)N and Al_(0.4)Ga_(0.6)N/Al_(0.5)Ga_(0.5)N superlattices.In general,the strain generated by BGa N/Al Ga N superlattice can compensate the hole concentration and improve the luminescent performance of Al Ga N based deep UV LEDs.

关 键 词：BGaN/AlGaN 超晶格 应变补偿 多量子阱 空穴浓度 发光二极管 

分 类 号：O472.3[理学—半导体物理] O474[理学—物理]