Investigation on Silicon Thin Film Solar Cells

The preparation, current status and trends are investigated for silicon thin film solar cells. The advantages and disadvantages of amorphous silicon thin film, polycrystalline silicon thin film and mono-crystalline silicon thin film solar cells are compared. The future development trends are pointed out. It is found that polycrystalline silicon thin film solar cells will be more promising for application with great potential.

Study on device simulation and performance optimization of the epitaxial crystalline silicon thin film solar cell

Because crystalline silicon thin film(CSiTF) solar cells possess the advantages of crystalline silicon solar cells such as high efficiency and stable performance and those of thin film solar cells such as low cost and so on,it is regarded as the next generation solar cell technology,which is most likely to replace the existing crystalline silicon solar cell technology.In this paper,we performed device simulation on the epitaxial CSiTF solar cell by using PC1D software.In order to make simulation results closer to the actual situation,we adopted a more realistic device structure and parameters.On this basis,we comprehensively and systematically investigated the effect of physical parameters of back surface field(BSF) layer,base and emitter,electrical quality of crystalline silicon active layer,situation of surface passivation,internal recombination and p-n junction leakage on the optoelectronic performance of the epitaxial CSiTF solar cell.Among various factors affecting the efficiency of the epitaxial CSiTF solar cell,we identified the three largest efficiency-affecting parameters.They are the base minority carrier diffusion length,the diode dark saturation current and the front surface recombination velocity in order.Through simulations,we found that the base is not the thicker the better,and the base minority carrier diffusion length must be taken into account when determining the optimal base thickness.When the base minority carrier diffusion length is smaller,the optimal base thickness should be less than or equal to the base minority carrier diffusion length;when the base minority carrier diffusion length is larger,the base minority carrier diffusion length should be at least twice the optimal base thickness.In addition,this paper not only illustrates the simulation results but also explains their changes from the aspect of physical mechanisms.Because epitaxial CSiTF solar cells possess a device structure that is similar to crystalline silicon solar cells,the conclusions drawn in this paper are also applied to crystalline silicon solar cells to a certain extent,particularly to thin silicon solar cells which are the hottest research topic at present.

Comparing Crystalline Silicon Solar Cells with Thin Film

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Research on the optimum hydrogenated silicon thin films for application in solar cells

Hydrogenated silicon （Si：H） thin films for application in solar ceils were deposited by using very high frequency plasma enhanced chemical vapour deposition （VHF PECVD） at a substrate temperature of about 170 ℃, The electrical, structural, and optical properties of the films were investigated. The deposited films were then applied as i-layers for p-i-n single junction solar cells. The current-voltage （I - V） characteristics of the cells were measured before and after the light soaking. The results suggest that the films deposited near the transition region have an optimum properties for application in solar cells. The cell with an i-layer prepared near the transition region shows the best stable performance.

Effect of emitter layer doping concentration on the performance of a silicon thin film heterojunction solar cell

A novel type of n/i/i/p heterojunction solar cell with a-Si：H（15 nm）/a-Si：H（10 nm）/epitaxial c-Si（47 p.m）/epitaxial c-Si（3 um） structure is fabricated by using the layer transfer technique, and the emitter layer is deposited by hot wire chemical vapour deposition. The effect of the doping concentration of the emitter layer Sd （Sd=PH3/（PH3 ＋SiH4＋H2）） on the performance of the solar cell is studied by means of current density-voltage and external quantum efficiency. The results show that the conversion efficiency of the solar cell first increases to a maximum value and then decreases with Sd increasing from 0.1% to 0.4%. The best performance of the solar cell is obtained at Sd = 0.2% with an open circuit voltage of 534 mV, a short circuit current density of 23.35 mA/cm2, a fill factor of 63.3%, and a conversion efficiency of 7.9%.

Fabrication of Poly-Si Thin Film on Glass Substrate by Aluminum-induced Crystallization

Amorphous silicon （ a-Si ） thin films were deposited on glass substrate by PECVD, and polycrystalline silicon （ poly- Si ） thin films were prepared by aluminum- induced crystallization （ AlC ）. The effects of annealing temperature on the microstructure and morphology were investigated. The AlC poly-Si thin films were characterized by XRD, Raman and SEM. It is found that a-Si thin film has a amorphous structure after annealing at 400℃ for 20 min, a-Si films begin to crystallize after annealing at 450 ℃ for 20 min, and the crystallinity of a-Si thin films is enhanced obviously with the increment of annealing termperature.

管式PECVD工艺对“SE+PERC”晶体硅太阳电池镀膜均匀性的影响及改善研究

针对在“SE+PERC”晶体硅太阳电池制备过程中,采用管式等离子体增强化学气相沉积(PECVD)工艺沉积正面钝化介质膜后,硅片正面会出现角部发红色差,即镀膜均匀性异常的问题,通过实验,对硅片厚度、工器具状态、背面膜层结构、正面钝化介质膜沉积工艺等影响因素对硅片正面角部发红色差的影响分别进行分析和讨论,并提出解决方案。研究结果表明:硅片正面角部发红色差的产生与硅片自身厚度、工器具状态、背面膜层结构、正面钝化介质膜沉积工艺均存在一定关系。通过采用最具优势的管式PECVD工艺条件,即优化自动化装片技术、控制石墨舟形变量、采用合适的背面膜层结构,以及正面钝化介质膜沉积工艺采用高射频功率叠加高腔体压力,可将正面角部发红色差硅片的占比降低至0%,从而可有效提升“SE+PERC”晶体硅太阳电池的成品率,提升生产线的经济效益。

Al-Induced Crystallization Growth of Si Films by Inductively Coupled Plasma Chemical Vapour Deposition

Polycrystalline Si （poly-Si） films are in situ grown on Al-coated glass substrates by inductively coupled plasma chemical vapour deposition at a temperature as low as 350℃. Compared to the traditional annealing crystalliza- tion of amorphous Si/Al-layer structures, no layer exchange is observed and the resultant poly-Si film is much thicker than Al layer. By analysing the depth profiles of the elemental composition, no remains of A1 atoms are detected in Si layer within the limit （〈0.01 at.%） of the used evaluations. It is indicated that the poly-Si material obtained by Al-induced crystallization growth has more potential applications than that prepared by annealing the amorphous Si/Al-layer structures.

Analysis of the p^+/p window layer of thin film solar cells by simulation

The application of a p~＋/p configuration in the window layer of hydrogenated amorphous silicon thin film solar cells is simulated and analyzed utilizing an AMPS-ID program.The differences between p~＋-p-i-n configuration solar cells and p-i-n configuration solar cells are pointed out.The effects of dopant concentration, thickness of p~＋-layer,contact barrier height and defect density on solar cells are analyzed.Our results indicate that solar cells with a p~＋-p-i-n configuration have a better performance.The open circuit voltage and short circuit current were improved by increasing the dopant concentration of the p~＋ layer and lowering the front contact barrier height.The defect density at the p/i interface which exceeds two orders of magnitude in the intrinsic layer will deteriorate the cell property.

Development of aluminum-doped ZnO films for a-Si:H/μc-Si:H solar cell applications

This study deals with the optimization of direct current（DC） sputtered aluminum-doped zinc oxide （AZO） thin films and their incorporation into a-Si：H/μc-Si：H tandem junction thin film solar cells aiming for high conversion efficiency.Electrical and optical properties of AZO films,i.e.mobility,carrier density,resistivity, and transmittance,were comprehensively characterized and analyzed by varying sputtering deposition conditions, including chamber pressure,substrate temperature,and sputtering power.The correlations between sputtering processes and AZO thin film properties were first investigated.Then,the AZO films were textured by diluted hydrochloric acid wet etching.Through optimization of deposition and texturing processes,AZO films yield excellent electrical and optical properties with a high transmittance above 81%over the 380-1100 nm wavelength range,lowsheet resistance of 11Ω/□and high haze ratio of 41.3%.In preliminary experiments,the AZO films were applied to a-Si：H/μc-Si：H tandem thin film solar cells as front contact electrodes,resulting in an initial conversion efficiency of 12.5%with good current matching between subcells.

太阳能电池的电势诱导衰减研究进展

在户外长期运行中,不论是晶体硅太阳能电池还是薄膜太阳能电池,都会受到电势诱导衰减(PID)的影响,从而导致太阳能电池组件输出功率下降。尽管前人已经开展了许多研究,但对PID现象的理解及解决方案仍旧不完整。本文主要介绍了晶体硅太阳能电池、薄膜太阳能电池的PID现象成因及相关解决办法,以促进人们对太阳能电池PID现象的深入理解,以期对太阳能电池的稳定性研究提供指导性意见。

Adoption of wide-bandgap microcrystalline silicon oxide and dual buffers for semitransparent solar cells in building-integrated photovoltaic window system

We focused on developing penetration-type semitransparent thin-film solar cells(STSCs) using hydrogenated amorphous Si(a-Si:H) for a building-integrated photovoltaic(BIPV) window system. Instead of conventional p-type a-Si:H, p-type hydrogenated microcrystalline Si oxide(p-μc-SiOx:H) was introduced for a wide-bandgap and conductive window layer. For these purposes, we tuned the CO2/SiH4 flow ratio(R) during p-μc-SiOx:H deposition. The film crystallinity decreased from 50% to 13% as R increased from 0.2 to 1.2. At the optimized R of 0.6, the quantum efficiency was improved under short wavelengths by the suppression of p-type layer parasitic absorption. The series resistance was well controlled to avoid fill factor loss at R = 0.6. Furthermore, we introduced dual buffers comprising p-a-SiOx:H/i-a-Si:H at the p/i interface to alleviate interfacial energy-band mismatch. The a-Si:H STSCs with the suggested window and dual buffers showed improvements in transmittance and efficiency from 22.9% to 29.3% and from 4.62% to 6.41%, respectively, compared to the STSC using a pristine p-a-Si:H window.

Simulation of high conversion efficiency and open-circuit voltages of α-si/poly-silicon solar cell

The P+ α-Si /N+ polycrystalline solar cell is molded using the AMPS-1D device simulator to explore the new high efficiency thin film poly-silicon solar cell. In order to analyze the characteristics of this device and the thickness of N+ poly-silicon, we consider the impurity concentration in the N+ poly-silicon layer and the work function of transparent conductive oxide (TCO) in front contact in the calculation. The thickness of N+ poly-silicon has little impact on the device when the thickness varies from 20 μm to 300 μm. The effects of impurity concentration in polycrystalline are analyzed. The conclusion is drawn that the open-circuit voltage (Voc) of P+ α-Si /N+ polycrystalline solar cell is very high, reaching 752 mV, and the conversion efficiency reaches 9.44%. Therefore, based on the above optimum parameters the study on the device formed by P+ α-Si/N+ poly-silicon is significant in exploring the high efficiency poly-silicon solar cell.

太阳能电池HIT产线镀膜工业自动装箱设备的研究

本文介绍了HIT太阳能电池的特点和应用前景,并设计研究生产线自动化装箱设备,设计一套由伺服电机、气缸驱动,利用PLC控制的机电一体化全自动装箱设备,可有效解决人工装箱工作劳动量大,耗费成本高的问题。

低温制备高质量多晶硅薄膜技术及其应用

多晶硅薄膜是集晶体硅材料和非晶硅氢合金薄膜优点于一体 ,在能源科学、信息科学的微电子技术中有广泛应用的一种新型功能材料。本文综述低温 ( <6 0 0℃ )制备高质量多晶硅薄膜技术的研究进展及其应用 ,着重讨论用等离子体化学气相沉积 (PECVD)硅基薄膜固相晶化制备多晶硅技术及其在薄膜硅太阳能电池上的应用。

光伏发电技术经济分析及发展预测

分析了光伏发电技术的发展现状和趋势,基于光伏发电系统单位电量发电成本(度电成本)影响因素的分析,结合国外典型光伏发电系统,对中国光伏发电度电成本进行了测算,并对光伏发电发展前景进行了研判,得出2050年前光伏发电发展路线。2020年前光伏产业将实现规模化发展,2020年后光伏发电将逐步成为具备市场竞争力的可再生能源发电技术。

太阳能电池研究进展

能源短缺和环境污染已成为影响经济社会发展的重要因素,能否获得无污染的能源成为当今社会关注的焦点之一。太阳能作为一种洁净的可再生能源得到了越来越多的重视。当前,在核电的安全问题日益突出的情况下,太阳能电池被认为是解决能源衰竭和环境污染等一系列重大问题的最佳选择。目前,许多国家正在制订中长期太阳能开发计划,准备在21世纪大规模开发太阳能。太阳能电池将太阳能直接转化为电能,是有效利用太阳能的最佳途径之一。综述了国内外包括单晶硅太阳能电池、多晶硅太阳能电池、薄膜太阳能电池等在内的太阳能电池的研究进展,对其制备技术、性能、转化效率以及应用领域进行了总结,讨论了它们各自的优势和劣势,并就太阳能电池未来的发展进行了展望。

太阳电池研究进展

晶体硅太阳电池主要朝高效方向发展,薄膜太阳电池特别是多晶硅薄膜太阳电池,由于其廉价,高效,是当前太阳电池研究的热点,也是未来太阳电池发展的方向。分别介绍了第一代、二代太阳电池的发展历程,着重介绍了第三代太阳电池的最新研究进展。

基于柔性玻璃衬底ZnO∶B薄膜的非晶硅太阳能电池的制备及其光电性能研究

采用低压化学气相沉积法(LPCVD)在大面积(40 cm×40 cm)超薄柔性玻璃和硬质玻璃衬底上分别制备了B掺杂的ZnO(BZO)透明导电薄膜及非晶硅薄膜太阳能电池,对比了两种衬底上BZO薄膜的形貌、光学和导电性能及其非晶硅薄膜电池的性能。结果表明,在相同LPCVD工艺下,超薄柔性玻璃衬底上BZO薄膜的生长速率相对减小;当生长相同厚度BZO薄膜时,超薄柔性玻璃衬底的透光率相对于硬质玻璃衬底提高约2%,同时并具有相同的导电能力。在柔性玻璃衬底上制备的非晶硅薄膜电池的初始和稳定转化效率也相对提高,分别达到9.16%和7.82%。