GaAs-based nanomaterials are essential for near-infrared nano-photoelectronic devices due to their exceptional optoelectronic properties.However,as the dimensions of GaAs materials decrease,the development of GaAs nan...GaAs-based nanomaterials are essential for near-infrared nano-photoelectronic devices due to their exceptional optoelectronic properties.However,as the dimensions of GaAs materials decrease,the development of GaAs nanowires(NWs)is hindered by type-Ⅱquantum well structures arising from the mixture of zinc blende(ZB)and wurtzite(WZ)phases and surface defects due to the large surface-to-volume ratio.Achieving GaAs-based NWs with high emission efficiency has become a key research focus.In this study,pre-etched silicon substrates were combined with GaAs/AlGaAs core-shell heterostructure to achieve GaAs-based NWs with good perpendicularity,excellent crystal structures,and high emission efficiency by leveraging the shadowing effect and surface passivation.The primary evidence for this includes the prominent free-exciton emission in the variable-temperature spectra and the low thermal activation energy indicated by the variable-power spectra.The findings of this study suggest that the growth method described herein can be employed to enhance the crystal structure and optical properties of otherⅢ-Ⅴlow-dimensional materials,potentially paving the way for future NW devices.展开更多
量子阱红外探测器(Quantum well infrared photodetector,QWIP)已经经历了20多年的深入研究,各种QWIP器件,包括量子阱红外探测器焦平面阵列(FPA)的研制也已经相当成熟。但是在国内,受制于整体工业水平,QWIP焦平面阵列器件的研制仍然处...量子阱红外探测器(Quantum well infrared photodetector,QWIP)已经经历了20多年的深入研究,各种QWIP器件,包括量子阱红外探测器焦平面阵列(FPA)的研制也已经相当成熟。但是在国内,受制于整体工业水平,QWIP焦平面阵列器件的研制仍然处于起步阶段。研制了基于GaAs/AlxGa1-xAs材料、峰值响应波长为9.9μm的长波320×256 n型QWIP焦平面阵列器件,其像元中心距25μm,光敏元面积为22μm×22μm。GaAs衬底减薄后的QWIP焦平面阵列,与Si基CMOS读出电路(ROIC)通过铟柱倒焊互连,并且在65 K工作温度下进行了室温环境目标成像。该焦平面器件的规模和成像质量相比之前国内报道的结果都有较大提高。焦平面平均峰值探测率达1.5×1010cm.Hz1/2/W。展开更多
在分子束外延生长量子阱材料过程中 ,分析了在不同的 Ga As/ Al Ga As异质结生长次序中 Ga的解吸附速率不同和量子阱中掺杂的扩散造成量子阱结构的不对称 ,讨论了 Ga As/ Al Ga As量子阱红外探测器的性能参数相对于正负偏压的不对称性 ...在分子束外延生长量子阱材料过程中 ,分析了在不同的 Ga As/ Al Ga As异质结生长次序中 Ga的解吸附速率不同和量子阱中掺杂的扩散造成量子阱结构的不对称 ,讨论了 Ga As/ Al Ga As量子阱红外探测器的性能参数相对于正负偏压的不对称性 ,并与金属有机化合物汽相沉淀法生长的量子阱材料和相应器件进行了比较 .发现 。展开更多
本文介绍了倒易点及其倒易点二维图的概念、倒易点形状及其倒易点二维图同晶格形变的关系 ,推导了热应力作用下双层膜发生弯曲的理论公式 ,阐明了晶格弯曲的原因和晶格倒易点二维图展宽的方向 ,分析了 Ga As光电阴极 Al Ga As/ Ga As外...本文介绍了倒易点及其倒易点二维图的概念、倒易点形状及其倒易点二维图同晶格形变的关系 ,推导了热应力作用下双层膜发生弯曲的理论公式 ,阐明了晶格弯曲的原因和晶格倒易点二维图展宽的方向 ,分析了 Ga As光电阴极 Al Ga As/ Ga As外延层的实测倒易点二维图 ,最后提出了降低 Al Ga As/ Ga展开更多
用分子束外延系统生长了 Ga As/ Al Ga As非对称耦合双量子阱 (ACDQW) ,用组合注入的方法 ,在同一块衬底上获得了不同注入离子和不同注入剂量的耦合量子阱单元 ,没有经过快速热退火过程 ,在常温下测量了不同单元的显微光荧光谱 ,发现子...用分子束外延系统生长了 Ga As/ Al Ga As非对称耦合双量子阱 (ACDQW) ,用组合注入的方法 ,在同一块衬底上获得了不同注入离子和不同注入剂量的耦合量子阱单元 ,没有经过快速热退火过程 ,在常温下测量了不同单元的显微光荧光谱 ,发现子带间跃迁能量最大变化范围接近 10 0 me V。展开更多
文摘GaAs-based nanomaterials are essential for near-infrared nano-photoelectronic devices due to their exceptional optoelectronic properties.However,as the dimensions of GaAs materials decrease,the development of GaAs nanowires(NWs)is hindered by type-Ⅱquantum well structures arising from the mixture of zinc blende(ZB)and wurtzite(WZ)phases and surface defects due to the large surface-to-volume ratio.Achieving GaAs-based NWs with high emission efficiency has become a key research focus.In this study,pre-etched silicon substrates were combined with GaAs/AlGaAs core-shell heterostructure to achieve GaAs-based NWs with good perpendicularity,excellent crystal structures,and high emission efficiency by leveraging the shadowing effect and surface passivation.The primary evidence for this includes the prominent free-exciton emission in the variable-temperature spectra and the low thermal activation energy indicated by the variable-power spectra.The findings of this study suggest that the growth method described herein can be employed to enhance the crystal structure and optical properties of otherⅢ-Ⅴlow-dimensional materials,potentially paving the way for future NW devices.
文摘介绍了 AlGaAs/GaAs 多量子阱红外探测器(QWIP)暗电流与噪声的关系和降低暗电流的途径;基手湿法化学腐蚀工艺制作了300μm×300μm台面单元器件,并用变温液氦杜瓦测试系统在不同温度下对红外探测器暗电流进行了测试并分析。在温度小于40 K 时,随着温度的改变暗电流没有明显的变化;当温度大于40 K 时,暗电流随着温度的升高迅速变大,正、负偏压下 QWIP 暗电流具有不对称特性。
文摘在分子束外延生长量子阱材料过程中 ,分析了在不同的 Ga As/ Al Ga As异质结生长次序中 Ga的解吸附速率不同和量子阱中掺杂的扩散造成量子阱结构的不对称 ,讨论了 Ga As/ Al Ga As量子阱红外探测器的性能参数相对于正负偏压的不对称性 ,并与金属有机化合物汽相沉淀法生长的量子阱材料和相应器件进行了比较 .发现 。
文摘本文介绍了倒易点及其倒易点二维图的概念、倒易点形状及其倒易点二维图同晶格形变的关系 ,推导了热应力作用下双层膜发生弯曲的理论公式 ,阐明了晶格弯曲的原因和晶格倒易点二维图展宽的方向 ,分析了 Ga As光电阴极 Al Ga As/ Ga As外延层的实测倒易点二维图 ,最后提出了降低 Al Ga As/ Ga
文摘用分子束外延系统生长了 Ga As/ Al Ga As非对称耦合双量子阱 (ACDQW) ,用组合注入的方法 ,在同一块衬底上获得了不同注入离子和不同注入剂量的耦合量子阱单元 ,没有经过快速热退火过程 ,在常温下测量了不同单元的显微光荧光谱 ,发现子带间跃迁能量最大变化范围接近 10 0 me V。
