Thermal Decomposition In Situ Monitoring System of the Gas Phase Cyclopentadienyl Tris(dimethylamino) Zirconium (CpZr(NMe2)3) Based on FT-IR and QMS for Atomic Layer Deposition

• Main Authors: Jong-Ki An, Eunmi Choi, Seob Shim, Hayeong Kim, Goru Kang, Ju-Young Yun
• Format: Article
• Language: English
• Published: SpringerOpen 2020-09-01
• Series: Nanoscale Research Letters
• Subjects: Thermal properties; In situ monitoring; FTIR&QMS; Precursor; CpZr[N(CH3)2]3
• Online Access: http://link.springer.com/article/10.1186/s11671-020-03400-2
• ISSN: 1556-276X

Abstract We developed a newly designed system based on in situ monitoring with Fourier transform infrared (FT-IR) spectroscopy and quadrupole mass spectrometry (QMS) for understanding decomposition mechanism and by-products of vaporized Cyclopentadienyl Tris(dimethylamino) Zirconium (CpZr(NMe2)3) during the move to process chamber at various temperatures because thermal decomposition products of unwanted precursors can affect process reliability. The FT-IR data show that the –CH3 peak intensity decreases while the –CH2– and C=N peak intensities increase as the temperature is increased from 100 to 250 °C. This result is attributed to decomposition of the dimethylamido ligands. Based on the FT-IR data, it can also be assumed that a new decomposition product is formation at 250 °C. While in situ QMS analysis demonstrates that vaporized CpZr(NMe2)3 decomposes to N-ethylmethanimine rather than methylmethyleneimine. The in situ monitoring with FT-IR spectroscopy and QMS provides useful information for understanding the behavior and decomposes of CpZr(NMe2)3 in the gas phase, which was not proven before. The study to understand the decomposition of vaporized precursor is the first attempt and can be provided as useful information for improving the reliability of a high- advanced ultra-thin film deposition process using atomic layer deposition in the future.