Contactless monitoring of Ge content and B concentration in ultrathin single and double layer Si1-xGex epitaxial films using multiwavelength micro-Raman spectroscopy

• Published in: AIP advances Vol. 2; no. 1; pp. 012124 - 012124-8
• Main Authors: Chang, Chun-Wei, Hong, Min-Hao, Lee, Wei-Fan, Lee, Kuan-Ching, Jang Jian, Shiu-Ko, Chuang, Yen, Fan, Yu-Ta, Hasuike, Noriyuki, Harima, Hiroshi, Ueda, Takeshi, Ishigaki, Toshikazu, Kang, Kitaek, Sik Yoo, Woo
• Format: Journal Article
• Language: English
• Published: AIP Publishing LLC 01.03.2012
• ISSN: 2158-3226; 2158-3226
• DOI: 10.1063/1.3681215

Non-contact monitoring of Ge content and B concentration in single and double Si1-xGex epitaxial layers on Si(100) device wafers was attempted using high-resolution, multiwavelength micro-Raman spectroscopy. The Ge content and B concentration determined by secondary ion mass spectroscopy (SIMS) depth profiling showed very strong correlation with the position and full-width-at-half-maximum of the Si-Si peak from the Si1-xGex epitaxial layers as determined by Raman measurements. High resolution X-ray diffraction (HRXRD) characterization was done for all wafers to determine Ge and B sensitivity and form comparisons with Raman and SIMS analysis. The non-destructive, in-line monitoring of Ge content and B concentration of single and double Si1-xGex epitaxial layers with thickness ranging from 5 ∼ 120 nm, on small area monitoring pads, was successfully demonstrated by multiwavelength micro-Raman spectroscopy during epitaxial process optimization, material property verification, and quality control applications.