IR and Raman absorption spectroscopic studies of APCVD, LPCVD and PECVD thin SiN films

Preparation and properties of clean Si3N4 surfaces

“…1b. H-free LPCVD films [29] show only an 811 cm À1 TO mode in this region, in agreement with the present results. For LPCVD films containing H [30], a TO mode asymmetrically broadened to higher energy is seen at about 835 cm À1 .…”

Low temperature–low hydrogen content silicon nitrides thin films deposited by PECVD using dichlorosilane and ammonia mixtures

“…Additionally, since silicon nitride films present very low absorption losses in the visible and infrared regions, and its index of refraction can be varied continuously over a wide range (1.7-3.0) by changing its composition, they are also very attractive for applications in thin film waveguides with desired characteristics of fiber match and compactness, and other integrated optical devices 0022 [8,9], and anti-reflecting and passivating coatings in silicon solar cells [10]. High quality silicon nitride films are usually prepared at high temperatures (700-800°C) by different thermally assisted chemical vapor deposition using mixtures of silane (SiH 4 ) and/or dichlorosilane (SiCl 2 H 2 ) and ammonia (NH 3 ) [11,12]. However, the advance of amorphous silicon technology and the continuous development of the microelectronic industry toward integrated circuits (IC) with nano-scale features, has demanded important reductions in the processing temperatures of silicon-compound thin films [13][14][15][16].…”

“…This requirement has widespread the use of diverse plasma enhanced chemical vapor deposition (PECVD) processes for depositing at low temperatures high quality silicon nitride films, such as electron cyclotron resonance [17,18], remote-PECVD [5,14,19], inductively coupled (IC) PECVD [16,20], and the conventional parallel plate-capacitive coupled PECVD [6,10,12,[21][22][23][24]. It should be mentioned that the latter PECVD version has continuously been of great interest because it has been largely studied and scaled-up to mass production dimensions in the production lines [21,25].…”

“…The use of halogenated silicon precursors like dichlorosilane (SiH 2 Cl 2 ), which contains less H atoms per Si atom than the SiH 4 molecule, has been proposed recently as a good alternative to reduce hydrogen incorporation in PECVD films deposited at 350-380°C, without reducing significantly the deposition rates compared with the corresponding thermal CVD process [11,12,20]. However, the reduction of substrate temperatures below 300°C, maintaining or even improving the physical and chemical properties of the silicon nitride films is a permanent challenge for materials science researchers.…”

Improving the dielectric properties of an electrowetting-on-dielectric microfluidic device with a low-pressure chemical vapor deposited Si3N4 dielectric layer

“…We have hence designed another dielectric fabrication of EWOD devices, using low-pressure chemical vapor deposited (LPCVD) Si 3 N 4 at small stress and low pressure as a smooth dielectric layer of high quality, as shown in Fig. 1(b), which exhibits a large permittivity, small rate of etching, a smooth surface, a small density of pinholes, 18,19 and sustained a greater voltage during operation compared with PECVD Si 3 N 4 .…”