Radio frequency bias power effects on silicon nitride film deposited in SiH4-NH3 using a plasma-enhanced chemical vapor deposition

Abstract

Silicon nitride films were deposited at room temperature in a plasma-enhanced chemical vapor deposition system. Ion energy and ion energy flux were measured with an ion energy analysis system. The effects of the radio frequency bias power on the ion energy distribution, deposition rate, refractive index, and surface roughness were examined along with the correlations between the ion energy diagnostics and film properties. The bias power varied from 30 W to 90 W. The surface roughness measured by atomic force microscopy was detailed in terms of the mean surface roughness and major pixel density. The deposition rate increased from 271 Å/min to 308 Å/min, increasing the bias power and correlation with the ion energy. Particularly, the refractive index increased with a decrease in the bias power. This is a unique feature resulting from the room-temperature deposition of silicon nitride film controlled in terms of the bias power. Moreover, the large variation from 1.94 to 2.49 facilitates the control of the refractive index as a function of the bias power. Strong dependency of the refractive index on the ion energy flux was also identified.

Neural Network Modeling of Ion Energy Impact on Surface Roughness of SiN Thin Films

“…SiN은 플라즈마 화학기상 증착(Plasma-enhanced chemical vapor deposition-PECVD)를 이용하여 300 o C 이상의 고온 에서 SiH 4 -N 2 , SiH 4 -NH 3 , 또는 SiH 4 -NH 3 -N 2 플라즈 마를 이용하여 제조되고 있다 1,2) . 최근에는 상온 (Room temperature)에서 제조된 연구결과가 보고 있 으며, 고온에서 제조된 것과 다른 특이 박막특성을 보였다 [3][4][5][6][7] . 예컨대, 소스전력의 감소에 따라 증착률 이 증가되거나 3) , 바이어스의 감소에 따른 굴절률의 증가 4 8) .…”

“…최근에는 상온 (Room temperature)에서 제조된 연구결과가 보고 있 으며, 고온에서 제조된 것과 다른 특이 박막특성을 보였다 [3][4][5][6][7] . 예컨대, 소스전력의 감소에 따라 증착률 이 증가되거나 3) , 바이어스의 감소에 따른 굴절률의 증가 4 8) . 공정변수(소 스전력, 압력 등)와 박막특성(증착률, 식각률 등) 간 의 모델링외에, 신경망은 공정 중 수집되는 in-situ 정보와 박막특성간의 모델링, 예컨대 optical emission spectroscopy 데이터와 식각특성간의 모델 9) , 또는 x-ray photoelectron spectroscopy와 같은 박막표면진 단특성과 표면거칠기의 모델링에 10 A + a * E h + bE l 참고문헌…”

Room temperature, ion energy-controlled deposition of silicon nitride films in a SiH4-N2 plasma

“…Another impact of the source power in a SiH 4 -N 2 pulsed plasma is the larger deposition rate at a shorter duty ratio [7]. With a decrease in the bias power in SiH 4 -NH 3 plasma, an increase in the refractive index and a decrease in the deposition rate were observed [8]. In a pulsed SiH 4 -NH 3 -N 2 plasma, a decrease in the refractive index with a reduction in the duty ratio was observed at most bias powers [9].…”

“…By exploring the relationships between the diagnostic variables and film properties, the bias power impact can be understood in detail. Recently, this was conducted for SiN films in SiH4-based plasmas especially in terms of the rf source or bias power [5][6][7][8][9]. However, there have been no attempts to investigate the effects of bias power on ion energy as well as the relationships between the bias powerinduced ion energy and film properties.…”

Growth of silicon nitride film by controlling plasma ion energy and duty ratio at room temperature

“…Due to a reduction of particles in the gas phase, a high deposition rate, and a reduced substrate heating, pulsed (P) plasma-applied deposition has been used for SiN deposition [4,8,9]. The deposition temperature has been lowered even to room temperature [10][11][12][13][14][15][16][17][18]. Low hydrogen SiN films at room temperature has been manufactured by using inductively coupled PECVD [10], P-PECVD [13,15,16], and electron cyclotron resonance-driven sputtering systems [11,12].…”