Plasma Characterization of Oxygen‐Tetramethylsilane Mixtures for the Plasma‐Enhanced CVD of SiO_xC_yH_z Thin Films

Abstract

The plasma-enhanced (PE)CVD of SiO x C y H z thin films from O 2 /Ar/tetramethylsilane (TMS) mixtures, in a low-pressure microwave electron cyclotron resonant (ECR) plasma reactor, has been studied. The discharge has been analyzed by mass spectrometry (MS) and optical emission spectroscopy (OES) for varying amounts of oxygen in the gas mixture both in the presence and in the absence of argon. The films obtained have been characterized by Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS). It is found that the electron impact of the TMS molecules and their dissociative ionization play an important role in the deposition process. Si(OH) x (CH 3 ) 3-x species, produced by reactions between the Si(CH 3 ) 4 molecule and Si(CH 3 ) 3 + ion fragments with O and O 2 , have been identified as important reaction intermediates.Such species form in different proportions depending on the O 2 /TMS ratio in the gas mixture. It is proposed that their incorporation onto the surface of the growing films accounts for the wide range of compositions achieved (ranging from SiO 2 to almost Si:C:H) and the high concentration of Si-C bonds experimentally detected in the SiO x C y H z thin films.

Optically Active Thin Films Deposited by Plasma Polymerization of Dye Molecules

“…[20,21] Basically, they consist of a series of emission lines involving the 4s-4p and 4s-5p excited states of Ar. The spectrum is significantly modified when the dye molecules are being evaporated over the substrate.…”

Calculation and analysis of electron transport coefficients in BF3-N2 and TMS-N2 gas mixtures

“…These electron transport coefficients were produced from reliable sets of electron collision cross section for TMS, BF 3 and N 2 molecules. Moreover, the remarkable synergism in the Townsend first ionization coefficient in the TMS-N 2 mixtures was also found out.…”

“…Tetramethylsilane (TMS), Si(CH 3 ) 4 , boron trifluoride (BF 3 ) and N 2 molecules in the form of pure are widely used in plasma processing such as plasma etching, plasma-enhanced chemical vapor deposition and doping plasma [1]- [8]. Moreover, these gases are not only used in the form of pure but also used in the form of mixtures with other gases depending on requirement of specific application.…”

“…Moreover, these gases are not only used in the form of pure but also used in the form of mixtures with other gases depending on requirement of specific application. The electron transport coefficients and electron collision cross section set for TMS, BF 3 and N 2 molecules have been determined. However, the electron transport coefficients in BF 3 -N 2 and TMS-N 2 mixtures in both experiments and theories are not available.…”

“…The electron transport coefficients and electron collision cross section set for TMS, BF 3 and N 2 molecules have been determined. However, the electron transport coefficients in BF 3 -N 2 and TMS-N 2 mixtures in both experiments and theories are not available. For expansion of the choices of TMS-N 2 and BF 3 -N 2 mixtures in plasma processing, these electron transport coefficients are necessary to determine.…”