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Highly conductive transparent films are of significant interest in the field of thin-film photovoltaics. ZnO-based films in particular have attracted much interest due to the low cost of materials with good film properties for CIGS and a-Si/µc-Si solar modules. Investigations have been ongoing at Fraunhofer IST into ceramic ZnO:Al₂O₃ targets from different manufacturers. This paper presents a comparison of target material, sputter characteristics and film properties of ZnO:Al. Sputter characteristics are in this case determined by voltage and current data showing arcing rates at different power loads and process pressures. ZnO:Al films are deposited by DC magnetron sputtering with various deposition parameters (e.g oxygen flow, total pressure, sputtering power and substrate temperature) and investigated with respect to optical and electrical properties.

Although much of the emphasis of Part 1 of this paper (in Photovoltaics International ed. 5) focused on material quality issues and attention to detail on process control, high-volume manufacturing requires a concerted effort to constantly improve productivity of the lamination process and in turn the productivity of the total module manufacturing line. Such is the competitive landscape that greater attention to these factors is becoming a key differentiator for both equipment suppliers and module manufacturers. In this, the second part of the lamination process focus, we will look closely at the dynamics impacting module prices and the developments being undertaken to improve cycle-times of the lamination process, overall productivity and optimization as well as costs to ensure future competitiveness.

It is not surprising that the photovoltaics industry has adopted many of the same metrics developed for the semiconductor industry. With suppliers serving both markets, Semiconductor Equipment and Materials International (SEMI) organized the PV Group to, among other things, look at the portability of standards between these two industries.  This paper will examine the application of two such standards, the Guide to Calculate Cost of Ownership (COO) Metrics for Semiconductor Manufacturing Equipment (SEMI E35) [1] and the Standard for Definition and Measurement of Equipment Productivity (SEMI E79) [2]. This latter standard is also known as overall equipment efficiency (OEE). Recent work at the National Renewable Energy Laboratory (NREL) regarding cost reduction also references SEMI E35. The application of these standards is examined using a case study comparing an in-line doping furnace and a phosphorus (POCl₃) batch furnace.

As 2009 comes to a close, many equipment suppliers are reflecting on the fact that the photovoltaic industry, despite its huge growth potential, can be a brutal place to do business. In the first half of the year many equipment suppliers had the unnerving experience of falling off a cliff, going from record order levels to no orders at all in the space of a few months. This sobering moment served as a reminder that the PV industry needs both access to finance and government support to continue growing. Indeed, it should be remembered that photovoltaics would still only be an interesting technology serving niche markets were it not for government subsidies. The one good thing about this year has been the accelerated drop in cell and panel prices. This is bringing ever closer the day when the price of PV generated electricity reaches parity with electricity generated from non-renewable sources and subsidies are no longer required. It is also driving a new round of investment in more efficient manufacturing equipment.

In most complex manufacturing environments, equipment failures dominate.  These failures are commonly referred to as 'fires' because of the chaos and damage they inflict on factory operations. For example, a key piece of equipment fails, creating a blockage in the production line. One or more personnel are quickly dispatched to fix the problem. The situation is dire, threatening to slow daily product starts and slip output goals. Those working the problem know this failure is of the utmost importance and know if they can just get the machine at an acceptable level, the stress from management will be lifted. Logic leads these personnel to suspect a specific component, which is then replaced. This paper discusses the best method of ensuring that this 'patching' of problems does not become part of the regular maintenance routine.

Solar currently represents less than 0.5% of global electricity generation. However, as renewable electricity gains importance in the US$1 trillion global electricity market, we forecast solar photovoltaic shipments to rise at a compound annual growth rate of 50% for the next four years. We expect an increasing number of countries to promote solar energy as the cost gap between solar and fossil fuel-generated electricity closes. This paper provides an overview of what to expect from the PV market in 2010.

Solar enterprises will each be faced with the occasional surplus or lack of solar modules in their lifetimes. In these instances, it is useful to adjust these stock levels at short notice, thus creating a spot market. Spot markets serve the short-term trade of different products, where the seller is able to permanently or temporarily offset surplus, while buyers are able to access attractive offers on surplus stocks and supplement existing supply arrangements as a last resort.

Building-integrated photovoltaics or BIPV is one form of solar electricity that looks set to dominate the solar market in the coming years. The increase in BIPV installations is already evident in some European countries as governments begin to tweak their policies in order to provide a platform for this technology. The past few months have seen countries such as France and Italy make efforts to up the installation rate of this integrated form of solar, increasing the feed-in tariff (FiT) rate quite substantially for BIPV and lowering it for the more common installations such as roof and ground-mounted systems in order to increase the uptake. This BIPV-dedicated section will focus on the new policies implemented in France and Italy, concentrating on France's policies as a blueprint for others. It will provide a focus on why governments are so keen to increase incentives in favour of BIPV and what the future implications of this market shift will be.

During the past few years, electroluminescence imaging has become a standard characterization technique for failure analysis and qualification of silicon wafer-based solar cells and modules. In contrast, the same analysis is not yet widely used for thin-film modules. This article demonstrates that electroluminescence analysis is a highly suitable tool for the in-depth investigation of Cu(In,Ga)Se₂ thin-film solar modules as well as for standard quality control. The reciprocity between the photovoltaic action and the electroluminescence emission of solar cell devices is used to derive quantitative relations that describe the voltage distribution within a solar module. Individual shunt spots in a module are not only visualized but their influence on the current voltage curves of the individual cells is quantitatively analyzed. Furthermore, device parameters like the sheet resistances of the window layer and the back contact are derived from the electroluminescence images

Despite the fall in silicon prices, wafer thickness continues to be reduced. The handling of thin wafers between 120 and 160µm is under research at the Fraunhofer IPA, where gripper-dependent and independent variables were determined as parameters for the handling process. Diverse grippers are tested on an automated test platform. Among these are grippers that are specifically designed for wafer handling, as well as others that are not but are used for wafer manipulation. The test platform includes several different test and handling equipments and utilizes critical parameters that might be required for achieving a high production rate via shortest cycle times to investigate the impact on thin wafers. The first results of the position accuracy measurement in relation to the physical movement parameters and other industrial key figures in ongoing handling research are presented within this paper.