自动硅片上料机的研制

近年来随着光伏产业发展,自动化设备在太阳能电池片生产线上得到广泛的运用。在工艺设备产能不断增长的背景下,对自动化设备的产能要求也越来越高。本文主要结合太阳能电池设计制造过程中硅片的上下料工艺,与传统上下料工艺的进行了对比。重点分析了太阳能自动化设备全自动硅片装片上下料机的结构、特性以及工作流程等。     

基于PLC的自动硅片翻片机的系统设计

在对翻转硅片功能分析的基础上,设计一种基于PLC控制的自动硅片翻片机,并详细讲解设备的组成、工作流程,探究控制系统中的硬件设计、工艺流程设计。自动硅片翻片机主要被应用于太阳能电池片印刷传送过程中,与国内外各种翻转技术对比,该翻片机控制系统具有良好的稳定性。     

光伏电池片生产中排除扩散炉故障的实验研究

在光伏电池片的生产过程中,扩散炉体的相关元器件经过频繁多次的使用致设备老化,常常会出现故障,使扩散后,硅片方块电阻异常波动,致生产线的扩散环节出现很多异常问题,导致PN结质量下降。文中对扩散炉体零器件老化、损坏而导致的方阻异常进行分析,并寻找相应的解决措施,不断提高PN结制造工艺的稳定性。     

太阳能电池互连片平行间隙电阻焊工艺优化

太阳能电池阵需要通过平行间隙电阻焊将大量太阳能电池单元与互连片串并联连接在一起以提供足够的能量。太阳能电池互连片平行间隙电阻焊过程影响因素较多,接头质量控制困难,并且缺乏有效的接头质量评价指标。通过有限元仿真结合红外热像测温试验,从焊接过程中的温度场分布角度进行分析,为太阳能电池互连片平行间隙电阻焊工艺参数优化以及质量检测提供参考。通过分析结果得到工艺参数的优化策略为焊接电压0.8 V,焊接时间50 ms,电极间隙0.2 mm,电极-互连片接触区域临界最优温度为900.2℃。     

振动热压烧结炉的设计研究

介绍了一种自主研发的用于难烧结陶瓷(如氮化铝、氮化硅、透明陶瓷等)的新型烧结设备——振动热压烧结炉,叙述了振动烧结炉的构成、主要指标、性能参数、振动烧结原理及振动烧结控制原理等。     

光伏电池生产车间自动化传输系统

在X公司现有太阳能电池生产线基础上,提出了一种衔接各个工艺环节设备之间的电池片自动化传输系统,实现了太阳能电池片生产线的自动化生产,并投入生产。通过实践检验,该自动换传输线能减少人工数量,有效提高生产效率以及产品质量。     

微波烧结工作原理及工业应用研究

微波烧结是一种利用微波加热对材料进行烧结的方法,它是一种快速制备高质量的新材料和使传统材料具有新的性能的重要技术手段.本文首先介绍了基本原理和技术特点,然后重点针对其技术的关键因素,提出了基于数字控制的双频微波烧结炉的相应硬件结构及应用方面的分析和研究,并对微波烧结技术的前景做出了展望.     

NTC442多线切割设备的设计改造

硅片是太阳能电池的核心材料。制造硅片主要设备是NTC442多线切割设备。NTC442多线切割设备采用了游离的切削模式,这种切削模式切削速度慢,切削质量差。针对这种情况,将对NTC442多线切割设备的游离切削模式改造成金刚石线的切削模式,改造了切割室,设计了主轴、匹配了轴承。改造后的设备,保证了硅片的质量、精度,提高了生产效率,应用前景十分广阔。     

悬浮式太阳能电池片搬送机器人系统实现

针对太阳能行业电池片搬送的需求,分析了现有机械推送式和接触吸取式的缺点,介绍了悬浮式太阳能电池片搬送机器人系统的工艺流程和技术要求,设计了各部分结构,特别对悬浮式搬送机器人机构的风刀、抓取手爪等核心部件的工作原理进行了分析。该设备的电控系统通过总线将人机界面、控制器与和执行器件连接,配线简单、维护方便、高速可靠。设备的实际运行验证了结构设计的合理性。设备通过在线传感系统与现有生产线密切配合,利于原有生产线的改造。     

氮化硅陶瓷滚动体的接触疲劳性能与组织

研究了Ｓｉ３Ｎ４－Ｙ２Ｏ３－Ａ１Ｎ系列热压烧结体的性能，分析表明其具有良好的常规性能，但由于烧结炉内氮气压较低（０．１Ｍｐａ），表面层发生脱氮，硅反应，使表面层性能下降，因而其接触疲劳性不理想。通过提高烧结炉内的氮气压下，可抑制不均匀表面层的形成。     

大直径太阳能硅片高效低损耗线切割技术研究

随着太阳能电池对大直径硅片的需求不断增加,大尺寸超薄硅片多线切割技术的发展趋势将日益明显。传统的外圆和内圆切割已经不能满足现有硅片大尺寸、小切缝、高质量和高效率的要求。本文对硅片切割方法、游离磨料多线切割基本原理、线切割硅片材料去除机理以及切割工艺因素进行了综述。     

The study on the atomic force microscopy base nanoscale electrical discharge machining

This study proposes an innovative atomic force microscopy (AFM) based nanoscale electrical discharge machining (AFM-based nanoEDM) system which combines an AFM with a self-produced metallic probe and a high-voltage generator to create an atmospheric environment AFM-based nanoEDM system and a deionized water (DI water) environment AFM-based nanoEDM system. This study combines wire-cut processing and electrochemical tip sharpening techniques on a 40-μm thick stainless steel sheet to produce a high conductive AFM probes, the production can withstand high voltage and large current. The tip radius of these probes is approximately 40 nm. A probe test was executed on the AFM using probes to obtain nanoscales morphology of Si wafer surface. The silicon wafer was as a specimen to carry out AFM-base nanoEDM process in atmospheric and DI water environments by AFM-based nanoEDM system. After experiments, the results show that the atmospheric and DI water environment AFM-based nanoEDM systems operate smoothly. From experimental results, it can be found that the electric discharge depth of the silicon wafer at atmospheric environments is a mere 14.54 nm. In a DI water environment, the depth of electric discharge of the silicon wafer can reach 25.4 nm. This indicates that the EDM ability of DI water environment AFM-based nanoEDM system is higher than that of atmospheric environment AFM-based nanoEDM system. After multiple nanoEDM process, the tips become blunt. After applying electrochemical tip sharpening techniques, the tip radius can return to approximately 40 nm. Therefore, AFM probes produced in this study can be reused.     

A study on soldering characteristics of laser tabbing system for crystalline silicon photovoltaic module production

The most significant task in the solar cell industry today is to minimize the cost of solar cell development, thereby establishing grid parity early. One way to achieve this goal is to reduce the thickness of silicon solar cell, which would subsequently result in reduction in raw silicon material costs. The most commonly used tabbing process in solar cell production today is the heating bar process. This process utilizes electric heating bars to heat the ribbons on solar cells. In this study, a laser tabbing machine was developed to overcome the problems of tabbing process of heating bar technique for a thin crystalline silicon solar cell. An electric test and peeling test were executed on soldering ribbon on solar cells. The results indicate that the bonding force of ribbon does not affect electrical output of the solar cell. The electric power of soldered solar cell was decreased around 5% in output as compared to the original unsoldered solar cell. The electric powers of the laser soldered module and the heating-bar soldered module were very close. The decline in efficiency of both modules was about 1.13%. As a result of this study, it was confirmed that the laser tabbing system developed in this research can be applied in module manufacturing processes.     

Thermal deformation analysis of tabbed solar cells using solder alloy and conductive film

Finite element analysis (FEA) has been carried out with the aim of understanding the thermal deformation characteristics of two solar cell configurations. One of the solar cell models is tabbed by lead-free solder, the other model by Conductive film (CF). A high temperature soldering process could weaken the bond and reduce the reliability of the cells because of the residual stress caused by the different thermal expansion coefficients of the materials. Moreover, solar irradiation generates temperature distribution across the surface of the solar cell, and the development of solar cells made of thinner crystalline silicon wafers will lead to the reduction in manufacturing costs. In this study, Finite element analysis (FEA) of the manufacturing process has been carried out using both solder and CF bonding. Three temperature cycles were applied to analyze different environmental operating conditions and understand how thermal cycles affect the residual stress during actual service conditions. This investigation provides a comparison of thermal deformations between solder and CF bonded solar cells in order to understand which offers substantial reliability in the long term. Also this study explores the effects of various thicknesses of the silicon wafer on the residual stress and deformation of the solar cells.     

一次生长多根硅芯设备的结构设计

多晶硅是单晶硅生产中必不可少的主要原料,硅芯是多晶硅生产过程中生长多晶的载体。而硅芯炉,主要用于生产多晶硅载体-硅芯。硅芯炉是在惰性气氛下,以高频感应加热,采用区熔法生长硅芯的设备,可一次同时生长多根硅芯,一炉次生产多组硅芯的设备。该设备由机械部分、电气控制部分以及高频电源三大部分组成。论文只对机械结构部份论述,其结构由底座、槽路支架、下传动、炉室、过渡付室、提拉头、真空系统、充气系统、水路等部分构成。     

A state-of-the-art review of ductile cutting of silicon wafers for semiconductor and microelectronics industries

Silicon is a typical functional material for semiconductor and optical industry. Many hi-tech products like lenses in thermal imaging, solar cells, and some key products of semiconductor industry are made of single crystal silicon. Silicon wafers are used as substrate to build vast majority of semiconductor and microelectronic devices. To meet high surge in demand for microelectronics based products in recent years, the development of rapid and cost efficient processes is inevitable to produce silicon wafers with high-quality surface finish. The current industry uses a sequence of processes such as slicing, edge grinding, finishing, lapping, polishing, back thinning, and dicing. Most of these processes use grinding grains or abrasives for material removal. The mechanism of material removal in these processes is fracture based which imparts subsurface damage when abrasive particles penetrate into the substrate surface. Most of these traditional processes are extremely slow and inefficient for machining wafers in bulk quantity. Moreover, the depth of subsurface damage caused by these processes can be up to few microns and it is too costly and time consuming to remove this damage by heavy chemical–mechanical polishing process. Therefore, semiconductor industry requires some alternative process that is rapid and cost effective for machining silicon wafers. Ductile cutting of silicon wafer has the potential to replace the tradition wafer machining processes efficiently. If implemented effectively in industry, ductile cutting of silicon wafers should reduce the time and cost of wafer machining and consequently improve the productivity of the process. This paper reviews and discusses machining characteristics associated with ductile cutting of silicon wafers. The limitations of traditional wafer fabrication, the driving factors for switching to ductile cutting technology, basic mechanism of ductile cutting, cutting mechanics, cutting forces, surface topography, thermal aspects, and important factors affecting these machining characteristics have been discussed to give a systematic insight into the technology.     

RESPONSE SURFACE ANALYSIS OF SLICING OF SILICON INGOTS WITH FOCUS ON PHOTOVOLTAIC APPLICATION

Polycrystalline silicon wafers are widely used in Photovoltaic (PV) industry as a base material for the solar cells. The existing silicon ingot slicing methods typically provide minimum wafer thickness of 300–350 μm and a surface finish of 3–5 μm R_a while incurring considerable kerf loss of 35–40%. Consequently, efficient dicing methods need to be developed, and in the quest for developing new processes for silicon ingot slicing, the wire-EDM (electric discharge machining) is emerging as a potential process. Slicing of a 3′′ square silicon ingot into wafers of 500 μm in thickness has been performed to study the process capability. This article analyzes the effect of processing parameters on the cutting process. The objective of the experimental study is improvement in slicing speed, minimization of kerf loss and surface roughness. A central composite design-based response surface methodology (RSM) has been used to study the slicing of polycrystalline silicon ingot via wire-EDM. A zinc-coated brass wire, 100 μm in diameter, has been used as an electrode in the slicing experiments. It has been observed that the optimal selection of the process parameters results in an increase of 40–50% in the slicing rate along with a 20% reduction in the kerf loss as compared to the conventional methods. The machined surfaces on the sliced wafer were free of micro-cracks and wire material contamination, thereby making it useful for electronic applications.     

一种降低硅片方块电阻方差的通过式扩散方法

为消除方块电阻不均匀性对太阳能电池板性能的影响,提出了一种通过式扩散方法。首先,设计了扩散炉结构,定义了通过式扩散方法的扩散步骤,并建立了方块电阻和扩散时间、扩散温度以及气体流量的关系的数学模型。其次,采用抽样统计方法,通过建立数学模型,计算各测试点的方块电阻及其方差,验证了该方法的有效性,为扩散工艺的改善提供借鉴。     

硅片边缘化学机械抛光的微小去除量测量

针对硅片化学机械抛光工艺的材料去除量非常微小并难以测量的问题,本文介绍一种采用表面粗糙度测量仪,对硅片边缘化学机械抛光的材料去除量进行一种简易、快速的测量方法,且该方法同时还可准确地测量硅片边缘抛光表面粗糙度值。检测结果表明,本方法较好地解决了硅片边缘化学机械抛光表面检测问题。     

微电铸工艺中含N’N-二乙基硫脲添加剂时金属铜填洞机理研究

为了研究含N’N-二乙基硫脲添加剂的微电铸工艺金属铜填洞机理,本文采用线性伏安法、循环电压电流溶出法(CVS)、扫描电镜(SEM)以及XRD测量法研究N’N-二乙基硫脲对微电铸工艺电化学行为的影响,并借助塔菲尔方程,研究微电铸铜反应过程中的电极动力学参数。结果显示：当微电铸铜工艺中加入N’N-二乙基硫脲添加剂时,产生活性极化,提高了铜离子还原时所需的活化能,金属离子的放电速度从2.2214 mA/ cm2降低 到约0.076 mA/ cm2,这样增加了反应时的过电位,促使电极表面晶核成型速度增加,晶体成长速度由2.57μm /min 降低到约0.17μm /min,铜离子的平滑能力提高约50%。这样可以有效减小微电铸时的边沿效应,使金属铜具有良好的填充微型孔洞的能力。本实验通过微电铸工艺成功地将金属铜填充入宽为10μm,深宽比为4：1的微型凹槽中,且镀层内没有空洞、空隙以及细缝等缺陷。