Direct detection of H atoms in the catalytic chemical vapor deposition of the SiH4/H2 system

Abstract

The absolute densities of H atoms produced in catalytic chemical vapor deposition (Cat-CVD or hot-wire CVD) processes were determined by employing two-photon laser-induced fluorescence and vacuum ultraviolet absorption techniques. The H-atom density in the gas phase increases exponentially with increases in the catalyzer temperature in the presence of pure H2. When the catalyzer temperature was 2200 K, the absolute density in the presence of 5.6 Pa of H2 (150 sccm in flow rate) was as high as 1.5×1014 cm−3 at a point 10 cm from the catalyzer. This density is one or two orders of magnitude higher than those observed in typical plasma-enhanced chemical vapor-deposition processes. The H-atom density decreases sharply with the addition of SiH4. When 0.1 Pa of SiH4 was added, the steady-state density decreased to 7×1012 cm−3. This sharp decrease can primarily be ascribed to the loss processes on chamber walls.

Catalytic Decomposition of H2O(D2O) on a Heated Ir Filament to Produce O and OH(OD) Radicals

“…H-atom ( ), O-atom ( ), and OH-radical ( ) densities calculated by the CHEMKIN software package. The preexponential factors for reactions (4) and (5) The OH-radical density obtained in the present system is higher than those obtained in the catalytic decomposition of H 2 /O 2 mixed systems [6,8]. However, that is less than those reported in plasma processes [32][33][34][35][36].…”

“…Since SiO x N y is less dense and more flexible compared to SiN x , that can be used as an interlayer to cover the microslits formed in SiN x films, which can be used as passivation films for organic light emitting diodes. The problem is that O 2 is reactive to SiH 4 , one of the most widely used source gases of silicon. The situation is similar when N 2 O is used as a source gas.…”

“…In this technique, radical species are produced from material gases on heated metal surfaces without co-producing ionic or metastable excited species. In order to make clear the decomposition and ejection mechanisms, many studies have been carried out to identify the radical species produced [3][4][5][6][7][8][9][10][11][12][13][14][15][16]. Although it has been rather difficult to produce oxidizing radicals, we have recently shown that atomic oxygen can be produced efficiently by the catalytic decomposition of O 2 , NO, N 2 O, and NO 2 on a heated Ir filament [7,8].…”

Enhancement of Photoresist Removal Rate by Using Atomic Hydrogen Generated under Low-pressure Conditions

“…As for the pressure dependence of the photoresist removal rate, Hashimoto et al have reported that there is no H 2 pressure dependence between 67 and 200 Pa [11]. It should be noted that the H-atom density saturates against the H 2 pressure under such high pressure conditions [26] and that the H atoms produced may be completely thermalized before arriving at the substrate surfaces. In our past study, we reported that the removal rate increases with hydrogen pressure between 0.4 and 7.2 Pa [12].…”

Laser-induced breakdown spectroscopy of trisilane using infrared CO2 laser pulses

“…8 LIB of silane ͑SiH 4 ͒ has been largely used in laser-induced chemical vapor deposition ͑CVD͒ and plasma-enhanced CVD for obtaining amorphous and hydrogenated silicon films. [9][10][11][12][13][14][15] Besides, higher silanes ͑disilane and trisilane͒, more effective in absorbing IR radiation, have been described as very suitable to act as precursors to a-Si: H films and from plasma decomposition induced by glow discharge. A major feature of these processes is a deposition rate enhancement of a factor of over 20 compared to monosilane.…”