TiO2 films were prepared by rf (13.56 MHz) magnetron sputtering using a mixture of Ar and O2 gases. At a total pressure of 2 mTorr, 100% rutile TiO2 films were successfully obtained on non heated substrates with rf power of 200 W, while 100% anatase TiO2 films were deposited at a pressure of 20 mTorr. Spatial profiles of both emission of excited species and plasma parameters were measured by optical emission spectroscopy (OES) and the Langmuir probe method. At a pressure of 2 mTorr, it was found that high-energy electrons are generated at a certain radial position near the cathode surface where the transverse magnetic field is maximum, and the strong localization of plasma was observed. It was proven that the energetic species impinging on the growing film are responsible for the formation of the rutile phase even if the substrate is at room temperature.

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Dissociations in plasma enhanced chemical vapor deposition for SiO2 deposition using tetraethoxysilane (TEOS) were investigated by means of mass spectrometry. First, we showed basic dissociation patterns of TEOS as a function of electron energy. It was shown that TEOS dissociates by electron impact at electron energies below 8 eV, removing the ethyl group (C2H5). Next, we presented dissociation patterns in TEOS/He plasma. Finally, dissociation in TEOS/O2 plasma was studied. It was shown that high molecular intermediate products containing carbon and hydrogen, such as Si(OC2H5)2H, Si(OC2H5)2OCH3, and Si(OC2H5)3OCH2, are present only in the TEOS/He plasma but not in the TEOS/O2 plasma. It was also shown that eliminated hydrocarbon gases such as C2H2, C2H4, C2H5, and OC2H5 are converted into H2O and CO2. Fourier-transformed infrared and x-ray photoelectron spectroscopy studies revealed that the degree of impurity concentration in the film decreased with increasing O2 concentration. Characteristics of metal–insulator–semiconductor devices reflected the degree of impurity concentration in the oxide films. It was found that oxygen gas plays an indispensable role for preparing high quality SiO2 films by oxidizing the intermediate dissociation products and eliminating hydrocarbon gases.

Dissociation in plasma enhanced chemical vapor deposition for SiO2 deposition using Tetraethoxysilane (TEOS) was investigated by means of mass spectrometry. First we showed basic dissociation patterns of TEOS by electron impact. It was shown that the TEOS was dissociated by electron impact at low electron energy below 7eV removing the ethyl group (C2H5). Next we presented dissociation patterns in TEOS/He plasma in order to eliminate the effect of oxidation. Finally dissociation in TEOS/O2 plasma was clarified. As the results, it was found that the oxidation plays a indispensable role for deposition of high quality SiO2 films due to the decrease in high molecular compounds with carbon (C) and hydrogen (H) although the TEOS is highly dissociated by electron impact.T. IEE Japan, Vol. 117-A, No. 8, '97

Dissociation in plasma‐enhanced chemical vapor deposition for SiO2 deposition using tetraethoxysilane (TEOS) was investigated by means of mass spectrometry. First we obtained the basic dissociation patterns of TEOS by electron impact. It was shown that TEOS was dissociated by electron impact at low electron energies below 7 eV, removing the ethyl group (C2H5). Next we determined dissociation patterns in TEOS/He plasma in order to eliminate the effect of oxidation. Finally, dissociation in TEOS/O2 plasma was investigated. It was found that oxidation plays an indispensable role in the deposition of high‐quality SiO2 films due to the decrease in high‐molecular‐weight compounds with carbon and hydrogen, although TEOS is highly dissociated by electron impact. © 1999 Scripta Technica, Electr Eng Jpn, 129(4): 32–38, 1999