单室沉积p-i-n型微晶硅薄膜太阳电池性能优化的研究

采用原位的氢等离子体处理技术和微晶覆盖技术来降低单室沉积p-i-n型微晶硅薄膜太阳电池中的硼污染问题.通过对不同处理技术所制备电池的电流密度-电压和量子效率测试结果的比较发现,一定的氢处理时间和合适的覆盖层技术都可以在一定程度上提高电池的性能,但每种方法的影响程度各异、文中对此异同进行了分析.通过对电池陷光结构和氢等离子体处理时间的优化,在单室中获得了效率为6.39%的单结微晶硅太阳电池.     

甚高频等离子体增强化学气相沉积法沉积μc-Si∶H薄膜中氧污染的初步研究

对不同的本底真空条件下,采用甚高频等离子体增强化学气相沉积技术沉积的氢化微晶硅（μc_Si∶H）薄膜中的氧污染问题进行了比较研究.对不同氧污染条件下制备的薄膜样品的x射线光电子能谱与傅里叶变换红外吸收光谱测量结果表明：μc_Si∶H薄膜中,氧以Si—O，O—O和O—H三种不同的键合模式存在,不同的键合模式源自不同的物理机理.μc_Si∶H薄膜的Raman光谱、电导率与激活能的测量结果进一步显示：沉积过程中氧污染程度的不同,对μc_Si∶H薄膜的结构特性与电学特性产生显著影响；而不同氧污染对μc_Si∶H薄膜电学特性的影响不同于氢化非晶硅（a_Si:H）薄膜. 关键词： 氢化微晶硅薄膜 甚高频等离子体增强化学气相沉积 氧污染     

甚高频高速沉积微晶硅薄膜的研究

采用甚高频化学气相沉积(VHF-PECVD)技术制备了系列微晶硅(μc-Si:H)薄膜样品,重点研究了硅烷浓度、功率密度、沉积气压和气体总流量对薄膜沉积速率和结晶状态的影响,绘制了沉积气压和功率密度双因素相图. 以0.75nm/s的高速沉积了器件质量级的微晶硅薄膜,并以该沉积速率制备出了效率为5.5%的单结微晶硅薄膜电池. 关键词： 微晶硅薄膜 高速沉积 甚高频化学气相沉积     

p种子层对单室制备微晶硅电池性能的影响

采用单室等离子体化学气相沉积技术沉积pin微晶硅电池时,硼污染降低了本征材料的晶化率并影响了p/i界面特性.针对该问题文中采用p种子层技术,即在沉积p层后采取高的H₂/SiH₄比率及适当的功率又沉积一个薄的p层,初步研究了p种子层对微晶硅i层纵向均匀性及电池性能的影响.实验结果表明：采用此方法能改善p/i界面特性,提高本征材料纵向结构的均匀性并降低硼对本征层的污染,有效地提高单结微晶硅电池的性能.最后,通过优化沉积条件,制备得到光电转换效率为881%（1 cm 关键词： 单室 甚高频等离子体增强化学气相沉积 微晶硅太阳电池 p种子层     

硼对沉积本征微晶硅薄膜特性的影响

采用甚高频等离子体增强化学气相沉积(VHF-PECVD)技术制备了不同腔室环境下的微晶硅薄膜.对单室沉积掺杂层p材料后遗留在腔室中的硼对本征微晶i材料电学特性和结构特性的影响进行了详细研究.测试结果表明：单室沉积p层后的硼降低了微晶i层材料的暗电导,增加了材料的光敏性;由于硼对i层污染程度的不同,使得材料的激活能发生了变化;腔室中残余的硼也导致微晶硅薄膜的结晶状况恶化,同时弱化了材料的(220)择优取向.而在较高功率和较强氢稀释下制备的晶化率较高,(220)晶向明显择优的材料受硼污染影响相对减小. 关键词： 单室 甚高频等离子体增强化学气相沉积 微晶硅 硼     

分步法高速沉积微晶硅薄膜

为提高微晶硅薄膜的纵向结晶性能, 在甚高频等离子体增强化学气相沉积技术的基础上, 采用过渡参数缓变和两步法相结合的方法在普通玻璃衬底上高速沉积薄膜. 当功率密度为2.1 W/cm², 硅烷浓度在6%和9.6%之间变化时, 从薄膜方向和玻璃方向测算的Raman晶化率的差异维持在2%以内. 硅烷浓度为9.6%时, 薄膜沉积速率可达3.43 nm/s, 从薄膜方向和玻璃方向测算的Raman晶化率分别为50%和48%, 差异的相对值仅为4.0%. 合理控制过渡阶段的参数变化, 可使两个方向的Raman晶化率差值下降到一个百分点. 表明采用新方法制备薄膜, 不仅可以抑制非晶孵化层的形成, 改善微晶硅薄膜的纵向结构, 还为制备优质薄膜提供了较宽的参数变化空间. 关键词： 微晶硅薄膜 非晶孵化层 高速沉积 甚高频等离子体增强化学气相沉积     

微晶硅薄膜的制备及结构和稳定性研究

采用甚高频等离子体增强化学气相沉积技术制备了不同衬底温度的微晶硅薄膜.利用傅里叶变换红外吸收对制备薄膜进行了结构方面的测试分析.结果表明：随衬底温度的升高，材料 中的氢含量总的趋势下降；傅里叶变换红外吸收和二次离子质谱测试结果都显示薄膜中氧含 量随衬底温度的升高而增加（在10¹⁹cm^-3量级）；与高衬底温度相 比，低衬底温度制备的材料易于后氧化，这说明低温制备材料的稳定性不好. 关键词： 甚高频等离子体增强化学气相沉积 微晶硅薄膜 傅里叶变换红外吸收     

甚高频等离子体增强化学气相沉积大面积平行板电极间真空电势差分布研究

采用二维准平面电路模型研究了甚高频等离子体增强化学气相沉积(VHF-PECVD)大面积平行板电极间真空电势差分布.计算结果表明：随平行板电极尺寸增加和激发频率提高,电势驻波效应成为影响电极间电势差非均匀分布的重要因素.在尺寸为1.2m×0.8m的大面积平行板电极上应用40.68和60MHz两种激发频率,通过功率馈入点数量和位置优化,计算获得非均匀性分别为±2.5%和±5.5%的真空电势差分布.这些数值计算结果为大面积平行板电极在VHF-PECVD中应用提供了重要的理论指导. 关键词： 二维准平面电路模型 甚高频等离子体增强化学气相沉积 电势驻波效应     

等离子体增强化学气相沉积工艺制备SiON膜及对硅的钝化

研究了等离子体增强化学气相沉积工艺条件对氮氧化硅膜的生长厚度及折射率的影响以及氮氧化硅/氮化硅叠层膜对p型硅片的钝化效果.实验结果表明,NH3的流量和N2O/SiH4流量比对氮氧化硅膜的影响较大,薄膜折射率能从1.48变化到2.1,厚度从30—60 nm不等.腔内压力和射频功率主要影响膜厚,压力越大,功率越大,沉积速率加快,生成的膜越厚.温度对膜厚和折射率的影响可以忽略.钝化效果显示,在有无NH3下,N2O/SiH4流量比分别为20和30时,退火后氮氧化硅/氮化硅叠层膜对p型硅的钝化效果最好,其潜在电压和少子寿命分别为652 mV,56.7μs和649 mV,50.8μs,均优于参照组氮化硅膜样品的钝化效果.     

高压射频等离子体增强化学气相沉积制备高效率硅薄膜电池的若干关键问题研究

报道了采用高压射频等离子体增强化学气相沉积(RF-PECVD) 制备高效率单结微晶硅电池和非晶硅/微晶硅叠层电池时几个关键问题的研究结果, 主要包括: 1)器件质量级本征微晶硅材料工艺窗口的确定及其结构和光电性能表征; 2)孵化层的形成机理以及减小孵化层的有效方法; 3)氢稀释调制技术对本征层晶化率分布及其对提高电池性能的作用; 4)高电导、高晶化率的微晶硅p型窗口层材料的获得, 及其对减小微晶硅电池p/i界面孵化层厚度和提高电池性能的作用等. 在解决上述问题的基础上, 采用高压RF-PECVD制备的单结微晶硅电池效率达8.16%, 非晶硅/微晶硅叠层电池效率11.61%.     

低速p/i界面缓冲层对高速沉积微晶硅太阳电池性能的影响

在采用高压高功率的甚高频等离子体增强化学气相沉积(VHF-PECVD)技术高速沉积微晶硅(μc-Si：H)太阳电池过程中,产生的高能离子对薄膜表面的轰击作用会降低薄膜质量和破坏p型掺杂层(p层)与本征层(i层)之间的界面特性.针对该问题提出在电池中引入低速沉积的p/i界面层的方法,即在p层上先低速沉积一薄层本征μc-Si：H薄膜,然后再高速沉积本征μc-Si：H薄膜.实验结果表明,引入低速方法沉积的界面层有效地提高了p/i界面特性和i层微结构的纵向均匀性,而随界面层厚度的增加,i层中的缺陷态先降低后增加, 关键词： μc-Si：H太阳电池 甚高频等离子体增强化学气相沉积 p/i界面层     

激发频率对VHF-PECVD制备微晶硅材料性能的影响

采用甚高频等离子增强化学气相沉积(VHF-PECVD)的方法制备了硅烷浓度分别为6％和7％， 随激发频率变化(40—70MHz)的氢化微晶硅(μc-Si∶H)薄膜材料.研究了材料的电学特性、 结构特性、沉积速率与激发频率之间的关系.结果发现材料的光敏性随频率的增加先降低后 提高，晶化率和沉积速率的变化趋势与之相反；在晶化率最高点，材料在(220)的晶向衍射 峰最高.并从光发射谱的角度研究了材料结构和沉积速率随频率变化的原因. 关键词： 甚高频等离子增强化学气相沉积 本征微晶硅 激发频率     

The high deposition of microcrystalline silicon thin film by very high frequency plasma enhanced chemical vapour deposition and the fabrication of solar cells

This paper reports that the intrinsic microcrystalline silicon ($\mu $c-Si:H) films are prepared with plasma enhanced chemical vapour deposition from silane/hydrogen mixtures at 200\du\ with the aim to increase the deposition rate. An increase of the deposition rate to 0.88\,nm/s is obtained by using a plasma excitation frequency of 75\,MHz. This increase is obtained by the combination of a higher deposition pressure, an increased silane concentration, and higher discharge powers. In addition, the transient behaviour, which can decrease the film crystallinity, could be prevented by filling the background gas with Hchemical vapour deposition, plasma deposition, solar cells, crystallinityProgram supported by the State Key Development Program for Basic Research of China (Grant No 2006CB202601), and Basic Research Project of Henan Province in China (Grant No 072300410140).7280N, 7830G, 8115HThis paper reports that the intrinsic microcrystalline silicon ($\mu $c-Si:H) films are prepared with plasma enhanced chemical vapour deposition from silane/hydrogen mixtures at 200\du\ with the aim to increase the deposition rate. An increase of the deposition rate to 0.88\,nm/s is obtained by using a plasma excitation frequency of 75\,MHz. This increase is obtained by the combination of a higher deposition pressure, an increased silane concentration, and higher discharge powers. In addition, the transient behaviour, which can decrease the film crystallinity, could be prevented by filling the background gas with Hchemical vapour deposition, plasma deposition, solar cells, crystallinityProgram supported by the State Key Development Program for Basic Research of China (Grant No 2006CB202601), and Basic Research Project of Henan Province in China (Grant No 072300410140).7280N, 7830G, 8115HThis paper reports that the intrinsic microcrystalline silicon ($\mu $c-Si:H) films are prepared with plasma enhanced chemical vapour deposition from silane/hydrogen mixtures at 200\du\ with the aim to increase the deposition rate. An increase of the deposition rate to 0.88\,nm/s is obtained by using a plasma excitation frequency of 75\,MHz. This increase is obtained by the combination of a higher deposition pressure, an increased silane concentration, and higher discharge powers. In addition, the transient behaviour, which can decrease the film crystallinity, could be prevented by filling the background gas with Hchemical vapour deposition, plasma deposition, solar cells, crystallinityProgram supported by the State Key Development Program for Basic Research of China (Grant No 2006CB202601), and Basic Research Project of Henan Province in China (Grant No 072300410140).7280N, 7830G, 8115HThis paper reports that the intrinsic microcrystalline silicon ($\mu $c-Si:H) films are prepared with plasma enhanced chemical vapour deposition from silane/hydrogen mixtures at 200\du\ with the aim to increase the deposition rate. An increase of the deposition rate to 0.88\,nm/s is obtained by using a plasma excitation frequency of 75\,MHz. This increase is obtained by the combination of a higher deposition pressure, an increased silane concentration, and higher discharge powers. In addition, the transient behaviour, which can decrease the film crystallinity, could be prevented by filling the background gas with Hchemical vapour deposition, plasma deposition, solar cells, crystallinityProgram supported by the State Key Development Program for Basic Research of China (Grant No 2006CB202601), and Basic Research Project of Henan Province in China (Grant No 072300410140).7280N, 7830G, 8115HThis paper reports that the intrinsic microcrystalline silicon ($\mu $c-Si:H) films are prepared with plasma enhanced chemical vapour deposition from silane/hydrogen mixtures at 200\du\ with the aim to increase the deposition rate. An increase of the deposition rate to 0.88\,nm/s is obtained by using a plasma excitation frequency of 75\,MHz. This increase is obtained by the combination of a higher deposition pressure, an increased silane concentration, and higher discharge powers. In addition, the transient behaviour, which can decrease the film crystallinity, could be prevented by filling the background gas with H$_{2}$ prior to plasma ignition, and selecting proper discharging time after silane flow injection. Material prepared under these conditions at a deposition rate of 0.78\,nm/s maintains higher crystallinity and fine electronic properties. By H-plasma treatment before i-layer deposition, single junction $\mu $c-Si:H solar cells with 5.5{\%} efficiency are fabricated.     

等离子体增强化学气相沉积法实现硅纳米线掺硼

用等离子体增强化学气相沉积(PECVD)方法成功实现硅纳米线的掺B.选用Si片作衬底，硅烷 （SiH4）作硅源，硼烷（B2H6）作掺杂气体， Au作催化剂，生长温度440℃.基于气-液-固(VLS)机制，探讨了掺B硅纳米线可能的生长机制.PECVD法化学成分配比更灵活，更容易实现纳米线掺杂，进一步有望生长硅纳米线pn结，为研制纳米量级器件提供技术基础. 关键词： 硅纳米线 化学气相沉积 纳米器件     

单室沉积高效非晶硅/微晶硅叠层太阳电池的研究

采用甚高频等离子体增强化学气相沉积技术,在前期单室沉积的微晶硅薄膜太阳电池和非晶硅/微晶硅叠层太阳电池研究的基础上,通过对微晶硅底电池本征层硅烷浓度的优化,获得了初始效率达到11.02%(电池面积1.0 cm²)的非晶硅/微晶硅叠层太阳电池.同时,100 cm²的非晶硅/微晶硅叠层太阳电池的组件效率也达到了9.04%. 关键词： 非晶硅/微晶硅叠层电池 单室 甚高频     

High critical oxygen concentration in microcrystalline silicon solar cells

For microcrystalline silicon based p–i–n solar cells the effect of deposition conditions on the critical oxygen concentration was investigated. All solar cells were prepared by 13.56 MHz plasma‐enhanced chemical vapour deposition. The critical oxygen concentration defines the lowest oxygen concentration in the intrinsic absorber layer causing a deterioration of the solar cell performance. For intentional contamination of ～1.2–1.3 µm thick i‐layers, the oxygen was inserted by a controllable leak at the process gases supply line, i.e. by a gas pipe leak. For µc‐Si:H deposited at a discharge power of 0.53 W/cm² we find a critical oxygen concentration of 1–2 × 10¹⁹ cm^–3 in agreement with values commonly reported in literature. However, changing the deposition conditions, we find that the critical oxygen concentration in µc‐Si:H cells is not fixed. At reduced power of 0.20 W/cm² a much higher value for the critical oxygen concentration of 1 × 10²⁰ cm^–3 is observed. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Monitoring of the growth of microcrystalline silicon by plasma‐enhanced chemical vapor deposition using in‐situ Raman spectroscopy

Raman spectra of microcrystalline silicon layers have been recorded in‐situ during growth. The spectra have been collected under realistic conditions for solar cell deposition. To enable these measurements an electrode with an optical feed through has been developed. By using a metallic grid to shield the feed through it is possible to achieve homogeneous deposition of µc‐Si:H at a sufficient optical transmission. In‐situ Raman measurements were carried out during the deposition of a layer with an intentionally introduced gradient in crystallinity that was seen in‐situ as well in reference measurements performed on the same layer ex‐situ. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)