Applications of Hadamard transform-gas chromatography/mass spectrometry for the detection of hexamethyldisiloxane in a wafer cleanroom

Yuan Kai Cheng, Cheng-Huang Lin, Samuel Kuo, Jonathan Yang, Szu Yuan Hsiung, Jia Lin Wang

研究成果: 雜誌貢獻文章

15 引文 斯高帕斯(Scopus)


The Hadamard transform-gas chromatography/mass spectrometry (HT-GC/MS) technique was successfully employed for the detection of hexamethyldisiloxane (HMDSO, C6H18OSi2) at the sub-nL/L level in a semiconductor wafer cleanroom. Indoor air samples were collected from the room, according to EPA Method TO-17 using a Tedlar bag where the air samples were allowed to pass through an absorption tube for 24h. The condensed components were then heated and simultaneously injected into a GC column through a Hadamard-injector, which was operated in accordance with the Hadamard codes. Compared to the single injection used in most GC/MS systems, the signal-to-noise (S/N) ratios were substantially improved after the inverse Hadamard transformation of the encoded chromatogram. Under optimized conditions, when cyclic S-matrix orders of 255, 1023 and 2047 were used, the S/N ratios of the HMDSO signals were substantially improved by 7.4-, 15.1- and 20.1-fold, respectively. These improvements are in good agreement with theoretically calculated values (8.0-, 16.0- and 22.6-fold, respectively). We found that when the HT-GC/MS technique was applied, HMDSO could be detected at the 0.1nL/L level.

頁(從 - 到)143-146
期刊Journal of Chromatography A
出版狀態已發佈 - 2012 一月 13


ASJC Scopus subject areas

  • Analytical Chemistry
  • Biochemistry
  • Organic Chemistry