調制電壓對掃描電容顯微鏡分析電性接面影像之影響

The Influence of Modulation Voltage in Scanning Capacitance Microscopy on the Observation of Electrical Junctions

胡晉瑋(Chin-Wei Hu) ； 張茂男(Mao-Nan Chang) ； 周棟煥(Tung-Huan Chou) ； 李耀仁(Yao-Jen Lee)

《科儀新知》 191期 (2012/12) Pp. 4-13

https://doi.org/10.29662/IT.201212.0001

摘要

掃描電容顯微術可用於定性分析半導體材料中載子濃度的分布及類型、電性接面深度、空乏區寬度、通道長度以及介電層品質等。本文將首度介紹暗模式掃描電容顯微術，並探討調制電壓對電性接面影像觀察的影響。暗模式掃描電容顯微術能完全排除光擾造成的電性接面影像失真，進而能提供研究人員深入觀察調制電壓對電性接面影像所造成之影響。研究結果顯示調制電壓過大，會造成窄化的電性接面影像，同時所觀察到的載子分布區域也會有擴張的情形，因此，使用暗模式掃描電容顯微術分析電性接面影像時，需使用較低的調制電壓才可得到精確可靠的分析結果。

並列摘要

Scanning capacitance microscopy (SCM) can qualitatively provides the distribution of carrier concentrations and types, electrical junction depths, widths of depletion regions, channel lengths and the quality of a dielectric layer. In this article, we for the first time introduced a dark-mode SCM and demonstrated the influence of modulation voltage (MV) on SCM images of electrical junctions without photopertubation. Dark-mode SCM can avoid junction image distortion induced by photoperturbations, allowing us to take a close look at the role of MV on SCM images of electrical junctions. Our experimental results indicated that higher MV may narrow the observed junction regions and broaden the carrier distribution. Therefore, using lower MV in dark-mode SCM is a reliable approach to precise SCM measurements.