\bfiIn situ Monitoring of Product Species in Plasma Etching by Fourier Transform Infrared Absorption Spectroscopy
- 1 July 1995
- journal article
- Published by IOP Publishing in Japanese Journal of Applied Physics
- Vol. 34 (7R)
- https://doi.org/10.1143/jjap.34.3731
Abstract
In situ Fourier transform infrared (FTIR) absorption spectroscopy has been used to detect reaction products resulting from the etching of Si in Cl2 plasmas. Silicon tetrachloride SiCl4 was the only gas-phase product species detected during etching. Unsaturated silicon chlorides SiCl x (x=1–3) were not observed in the plasma within the present level of detection. By comparing the absorbances of SiCl4 in Cl2 plasma etching of Si and in pure SiCl4 gases, it is suggested that the concentrations of SiCl4 or product species during etching are comparable to the feedstock Cl2 gas densities, e.g., [SiCl4] ∼1 ×1013 cm-3 at a pressure of 0.5 mTorr. In contrast, on the surface-etched Si, unsaturated silicon chlorides SiCl x (x=1–3) as well as SiCl4 were found to occur by FTIR reflection absorption spectroscopy (RAS). Moreover, absorption features of silicon oxides were observed both in the gas phase and on the surface, presumably arising from reactions between Si produced from etching and oxygen included in the reactor chamber owing to a small leak.Keywords
This publication has 28 references indexed in Scilit:
- Chemical Kinetics of Chlorine in Electron Cyclotron Resonance Plasma Etching of SiJapanese Journal of Applied Physics, 1994
- Influence of pressure on nitrogen incorporation in ultraviolet chemical vapor deposited SiO2 filmsJournal of Applied Physics, 1993
- Novel Technique of Infrared Reflection Absorption Spectroscopy for Si Surface StudyJapanese Journal of Applied Physics, 1993
- Transformer coupled plasma etch technology for the fabrication of subhalf micron structuresJournal of Vacuum Science & Technology A, 1993
- A Study on the Behavior of SiO2 Film Precursors with Trench Deposition Method for SiH4/O2 Low Pressure Chemical Vapor DepositionJapanese Journal of Applied Physics, 1991
- Vibrational and rotational excitation in a capacitively coupled 13.56 MHz radio frequency CF4 plasma studied by infrared absorption spectroscopyJournal of Vacuum Science & Technology A, 1991
- Detection of dry etching product species with i n s i t u Fourier transform infrared spectroscopyJournal of Vacuum Science & Technology B, 1989
- Ion-assisted etching of silicon by molecular chlorineJournal of Vacuum Science & Technology A, 1984
- Optical Phonons in Amorphous Silicon Oxides. I. Calculation of the Density of States and Interpretation of Lo-To Splittings of Amorphous Sio2Physica Status Solidi (b), 1983
- Intermolecular interactions in liquid and gaseous SiCl4Spectrochimica Acta Part A: Molecular Spectroscopy, 1974