Hydrogenated microcrystalline silicon (μc-Si:H) thin films were prepared by high- pressure radio-frequency (13.56 MHz) plasma enhanced chemical vapor deposition (rf-PECVD) with a screened plasma. The deposition rate ...Hydrogenated microcrystalline silicon (μc-Si:H) thin films were prepared by high- pressure radio-frequency (13.56 MHz) plasma enhanced chemical vapor deposition (rf-PECVD) with a screened plasma. The deposition rate and crystallinity varying with the deposition pressure, rf power, hydrogen dilution ratio and electrodes distance were systematically studied. By optimizing the deposition parameters the device quality μc-Si:H films have been achieved with a high deposition rate of 7.8 /s at a high pressure. The Voc of 560 mV and the FF of 0.70 have been achieved for a single-junction μc-Si:H p-i-n solar cell at a deposition rate of 7.8 /s.展开更多
For ZnO/diamond structured surface acoustic wave （SAW） filters, performance is sensitively dependent on the quality of the ZnO films. In this paper, we prepare highly-oriented and fine grained polycrystalline ZnO th...For ZnO/diamond structured surface acoustic wave （SAW） filters, performance is sensitively dependent on the quality of the ZnO films. In this paper, we prepare highly-oriented and fine grained polycrystalline ZnO thin films with excellent surface smoothness on the smooth nucleation surfaces of freestanding CVD diamond films by metal organic chemical vapour deposition （MOCVD）. The properties of the ZnO films are characterized by x-ray diffraction （XRD）, scanning electron microscopy （SEM）, and photoluminescence （PL） spectrum. The influences of the deposition conditions on the quality of ZnO films are discussed briefly. ZnO/freestanding thick-diamond-film layered SAW devices with high response frequencies are expected to be developed.展开更多
采用RF PECVD方法,在P a SiC:H薄膜沉积技术基础上,通过逐步减小碳、硼的掺杂浓度,增大氢稀释率,使材料从非晶态向微晶态转变,在获得本征微晶材料之后,再逐步增大硼掺杂浓度,得到P型微晶硅薄膜材料(暗电导率为5.22×10-3S/cm,光学...采用RF PECVD方法,在P a SiC:H薄膜沉积技术基础上,通过逐步减小碳、硼的掺杂浓度,增大氢稀释率,使材料从非晶态向微晶态转变,在获得本征微晶材料之后,再逐步增大硼掺杂浓度,得到P型微晶硅薄膜材料(暗电导率为5.22×10-3S/cm,光学带隙大于2.0eV)。在这个过程中可以明显观察到碳、硼抑制材料晶化的作用。展开更多
采用射频等离子体增强化学气相沉积（RF-PECVD）法在低温、低功率的条件下制备了一系列本征硅薄膜,研究了硅烷浓度（CS）对薄膜微结构、光电特性及表面钝化性能的影响.将本征硅薄膜作为钝化层应用到氢化纳米晶硅/晶硅（nc-Si：H/c-Si）...采用射频等离子体增强化学气相沉积（RF-PECVD）法在低温、低功率的条件下制备了一系列本征硅薄膜,研究了硅烷浓度（CS）对薄膜微结构、光电特性及表面钝化性能的影响.将本征硅薄膜作为钝化层应用到氢化纳米晶硅/晶硅（nc-Si：H/c-Si）硅异质结（SHJ）太阳电池中,研究了硅烷浓度和薄膜厚度对电池性能的影响.实验发现：随着硅烷浓度的降低,本征硅薄膜的晶化率、氢含量、结构因子、光学带隙和光敏性等都在过渡区急剧变化;本征硅薄膜的钝化性能由薄膜的氢含量及氢的成键方式决定.靠近过渡区的薄膜具有较好的致密性和光敏性,氢含量最高,带隙态密度低,且主要以Si H形式成键,对硅片表现出优异的钝化性能,使电池的开路电压大幅提高.但是,当薄膜的厚度过小时,会严重影响其钝化质量.本实验中,沉积本征硅薄膜的最优硅烷浓度为6%（摩尔分数）,且当薄膜厚度为~8 nm时,所制备电池的性能最好.实验最终获得了开路电压为672 m V,短路电流密度为35.1 m A·cm-2,填充因子为0.73,效率为17.3%的nc-Si：H/c-Si SHJ太阳电池.展开更多
基金Supported by the National Natural Science Foundation of China (Grant No. 50662003)the State Development Program for Basic Research of China (Grant No. G2000028208)
文摘Hydrogenated microcrystalline silicon (μc-Si:H) thin films were prepared by high- pressure radio-frequency (13.56 MHz) plasma enhanced chemical vapor deposition (rf-PECVD) with a screened plasma. The deposition rate and crystallinity varying with the deposition pressure, rf power, hydrogen dilution ratio and electrodes distance were systematically studied. By optimizing the deposition parameters the device quality μc-Si:H films have been achieved with a high deposition rate of 7.8 /s at a high pressure. The Voc of 560 mV and the FF of 0.70 have been achieved for a single-junction μc-Si:H p-i-n solar cell at a deposition rate of 7.8 /s.
文摘For ZnO/diamond structured surface acoustic wave （SAW） filters, performance is sensitively dependent on the quality of the ZnO films. In this paper, we prepare highly-oriented and fine grained polycrystalline ZnO thin films with excellent surface smoothness on the smooth nucleation surfaces of freestanding CVD diamond films by metal organic chemical vapour deposition （MOCVD）. The properties of the ZnO films are characterized by x-ray diffraction （XRD）, scanning electron microscopy （SEM）, and photoluminescence （PL） spectrum. The influences of the deposition conditions on the quality of ZnO films are discussed briefly. ZnO/freestanding thick-diamond-film layered SAW devices with high response frequencies are expected to be developed.
文摘采用RF PECVD方法,在P a SiC:H薄膜沉积技术基础上,通过逐步减小碳、硼的掺杂浓度,增大氢稀释率,使材料从非晶态向微晶态转变,在获得本征微晶材料之后,再逐步增大硼掺杂浓度,得到P型微晶硅薄膜材料(暗电导率为5.22×10-3S/cm,光学带隙大于2.0eV)。在这个过程中可以明显观察到碳、硼抑制材料晶化的作用。
文摘采用射频等离子体增强化学气相沉积（RF-PECVD）法在低温、低功率的条件下制备了一系列本征硅薄膜,研究了硅烷浓度（CS）对薄膜微结构、光电特性及表面钝化性能的影响.将本征硅薄膜作为钝化层应用到氢化纳米晶硅/晶硅（nc-Si：H/c-Si）硅异质结（SHJ）太阳电池中,研究了硅烷浓度和薄膜厚度对电池性能的影响.实验发现：随着硅烷浓度的降低,本征硅薄膜的晶化率、氢含量、结构因子、光学带隙和光敏性等都在过渡区急剧变化;本征硅薄膜的钝化性能由薄膜的氢含量及氢的成键方式决定.靠近过渡区的薄膜具有较好的致密性和光敏性,氢含量最高,带隙态密度低,且主要以Si H形式成键,对硅片表现出优异的钝化性能,使电池的开路电压大幅提高.但是,当薄膜的厚度过小时,会严重影响其钝化质量.本实验中,沉积本征硅薄膜的最优硅烷浓度为6%（摩尔分数）,且当薄膜厚度为~8 nm时,所制备电池的性能最好.实验最终获得了开路电压为672 m V,短路电流密度为35.1 m A·cm-2,填充因子为0.73,效率为17.3%的nc-Si：H/c-Si SHJ太阳电池.
