Studies of thin strained InAs, AlAs, and AlSb layers by spectroscopic ellipsometry
Studies of thin strained InAs, AlAs, and AlSb layers by spectroscopic ellipsometry
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DOI：
10.1063/1.361137
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发表时间：
1996-03
影响因子：
3.2
通讯作者：
C. Herzinger;P. G. Snyder;F. Celii;Y. Kao;D. Chow;B. Johs;J. Woollam
中科院分区：
文献类型：
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作者：
C. Herzinger;P. G. Snyder;F. Celii;Y. Kao;D. Chow;B. Johs;J. Woollam
应变InAs、AlAs和AlSb薄层的光学常数已经通过椭圆偏振光谱和多样品分析进行了研究。这些材料对于AlAs/InAs/In0.53Ga0.47As和AlSb/InAs材料系统中的高速共振隧穿二极管非常重要。了解这些薄层的光学性质是很重要的发展原位生长控制使用光谱椭圆偏振。对多个样本进行了非原位室温测量。得到的拟合光学常数被解释为表观值，因为它们取决于拟合模型和样品结构。非常薄的层的这些表观光学常数可能取决于厚度和周围材料，并且通常仅适用于在类似结构背景下发现的层。应变层和薄无应变帽层的光学常数的临界点特征被发现与体值不同，并且三个主要效应（应变，量子限制和薄势垒临界点加宽）已被确定为负责。在这三者中，薄势垒材料的E1和E1+Δ1临界点的加宽是最新和最明显的。这种薄势垒效应被证明是一种独立于应变的效应，并且在AlAs/GaAs系统中也可以观察到。应变InAs、AlAs和AlSb薄层的光学常数已经通过椭圆偏振光谱和多样品分析进行了研究。这些材料对于AlAs/InAs/In0.53Ga0.47As和AlSb/InAs材料系统中的高速共振隧穿二极管非常重要。了解这些薄层的光学性质是很重要的发展原位生长控制使用光谱椭圆偏振。对多个样本进行了非原位室温测量。得到的拟合光学常数被解释为表观值，因为它们取决于拟合模型和样品结构。非常薄的层的这些表观光学常数可能取决于厚度和周围材料，并且通常仅适用于在类似结构背景中发现的层。应变层和薄的无应变帽层的光学常数的临界点特征被发现不同于体值，和三个主要的影响（应变，…
The optical constants for thin layers of strained InAs, AlAs, and AlSb have been investigated by spectroscopic ellipsometry and multi‐sample analyses. These materials are important for high‐speed resonant tunneling diodes in the AlAs/InAs/In0.53Ga0.47As and AlSb/InAs material systems. Understanding the optical properties for these thin layers is important for developing in situ growth control using spectroscopic ellipsometry. Ex situ room‐temperature measurements were made on multiple samples. The resulting fitted optical constants are interpreted as apparent values because they are dependent on the fit model and sample structure. These apparent optical constants for very thin layers can be dependent on thickness and surrounding material, and are generally applicable only for layers found in a similar structural context. The critical point features of optical constants for the strained layers and for the thin unstrained cap layers were found to differ from bulk values, and three principle effects (strain, quantum confinement, and thin‐barrier critical‐point broadening) have been identified as responsible. Of these three, the broadening of the E1 and E1+Δ1 critical points for thin barrier material is the newest and most pronounced. This thin barrier effect is shown to be a separate effect from strain, and is also observable for the AlAs/GaAs system.The optical constants for thin layers of strained InAs, AlAs, and AlSb have been investigated by spectroscopic ellipsometry and multi‐sample analyses. These materials are important for high‐speed resonant tunneling diodes in the AlAs/InAs/In0.53Ga0.47As and AlSb/InAs material systems. Understanding the optical properties for these thin layers is important for developing in situ growth control using spectroscopic ellipsometry. Ex situ room‐temperature measurements were made on multiple samples. The resulting fitted optical constants are interpreted as apparent values because they are dependent on the fit model and sample structure. These apparent optical constants for very thin layers can be dependent on thickness and surrounding material, and are generally applicable only for layers found in a similar structural context. The critical point features of optical constants for the strained layers and for the thin unstrained cap layers were found to differ from bulk values, and three principle effects (strain,...