Effect of Radio Frequency Power on the Properties of Hydrogenated Amorphous Carbon Films Grown by Radio Frequency Plasma-Enhanced Chemical Vapor Deposition.
Effect of Radio Frequency Power on the Properties of Hydrogenated Amorphous Carbon Films Grown by Radio Frequency Plasma-Enhanced Chemical Vapor Deposition.
复制标题
射频功率对射频等离子体增强化学气相沉积生长的氢化非晶碳薄膜性能的影响。
DOI：
10.1143/jjap.39.4088
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发表时间：
2000
影响因子：
1.5
通讯作者：
T. Jimbo
中科院分区：
文献类型：
--
作者：
Y. Hayashi;K. Hagimoto;H. Ebisu;Murali Krishna Kalaga;T. Soga;M. Umeno;T. Jimbo
研究了射频（RF）功率对射频等离子体增强化学气相沉积（RF plasma enhanced chemical vapor deposition，CVD）法制备的氢化非晶碳（a-C：H）薄膜材料性能的影响。射频功率对薄膜的电子自旋共振（ESR）自旋密度、光学带隙、化学键合和光致发光（PL）等性质有显著影响。拉曼光谱、红外（IR）吸收和ESR测量表明，由于sp2 C-Hx组分的增加，残余缺陷密度（ESR自旋密度）随着RF功率的增加而增加。我们在低射频功率下获得了8 ×1016 spins/cm ~ 3的ESR自旋密度，这与高质量的非晶硅薄膜相当。等离子体发射光谱表明，氢峰（IH）和烃峰（IC-H）之间的强度比（IC-H/IH）显着降低与RF功率的增加。的光学带隙，从紫外-可见光谱，从3.0到1.9 eV的变化，随着RF功率的增加。在较低的RF功率下沉积的样品的PL谱中观察到以2.4 eV为中心的宽发射带。通过比较在≤100 W RF功率下沉积的薄膜的PL发射和吸收系数谱，我们发现了0.5-0.3 eV的斯托克斯位移，而在>100 W RF功率下沉积的薄膜中，我们未能观察到明显的斯托克斯位移。PL峰和光学带隙之间的弱相关性被证明。
We have studied the influence of radio frequency (RF) power on material properties of hydrogenated amorphous carbon (a-C:H) films prepared by RF plasma-enhanced chemical vapor deposition (CVD). The RF power has a significant impact on film properties such as electron spin resonance (ESR) spin density, the optical band gap, chemical bonding and photoluminescence (PL). Raman spectroscopy, infrared (IR) absorption and ESR measurements reveal that the residual defect density (ESR spin density) increases with increasing RF power due to the increase of sp2 C–Hx components. We obtained an ESR spin density as small as 8 ×1016 spins/cm3 at a low RF power, which is comparable to that of high-quality amorphous silicon films. Plasma optical emission spectroscopy indicates that the intensity ratio (IC–H/IH) between hydrogen peaks (IH) and hydrocarbon peaks (IC–H) significantly decreases with increasing RF power. The optical band gap, obtained from UV-visible spectroscopy, varies from 3.0 to 1.9 eV with increasing RF power. The broad emission band centered around 2.4 eV was observed in the PL spectra of the samples deposited at lower RF powers. We found a 0.5–0.3 eV Stokes shift by comparing the PL emission and the absorption coefficient spectrum from the films deposited at ≤100 W RF powers, whereas, we failed to observe a clear Stokes shift from the films deposited at >100 W RF powers. A weak correlation between the PL peak and the optical band gap is demonstrated.