Enabling growth


Advanced manufacturing technologies are often seen primarily as reducing the cost of manual labor by replacing humans in various steps and processes in PV production to reduce labor expenses. Yet if that was the case, automation would only be gaining ground in high labor cost countries. In fact, equipment suppliers are addressing a global market. What is new is the increasing use of automation in module manufacturing to improve quality and increase production capacity.
A strong trend contributing to global demand for new technologies is the international expansion of established PV manufacturers to be nearer to their customers. Even when U.S. and European companies establish plants in countries with lower labor cost, their factories are exploiting the latest technologies. Here the motivation for automation is the desire to maintain quality, while growing quickly and economically. Also, the quest for greater cell efficiency and module performance continues to drive demand for automation and robotics.
In thin film PV production, particularly in the front end phase of cell processing, automation is a key enabler of production regardless of whether the factory is in Silicon Valley or Greater Noida. The size and weight of the glass substrates and the need for cleanroom environments are main reasons for that. Plus, in some cases the high temperatures make the work not fit for human handling, according to Stefan Huttelmaier, Sales Engineer at Schiller Automation. In other words, without automation and robotics the process would be unwieldy.
The same goes for several processes in crystalline PV manufacturing. For example, automation is widely used in handling systems and tools for polysilicon materials. “Wherever the loading and unloading of ingots, wafers and cells is tricky due to the interfaces of the process tool, automation is already in use,” comments Vinay Shah, Manager of new crystalline products at Applied Materials.
The growth of automation vendor Jonas & Redmann in East Asia makes it clear that there is not only a market for crystalline cell processing solutions for loading and unloading diffusion furnaces and plasma processing in high labor cost nations. “We have well over a thousand installations. The fact that we have sales and service teams in Taiwan, Korea, and China speaks for the demand there.” says Jonas & Redmann’s Spokesperson Olga Bosch.
Another piece of evidence that automation is not only on the rise in high labor cost countries comes from ABB Robotics. It counts China as its second largest market for all types of industrial robotics. In PV, its Flexpicker is used worldwide and is the bestseller for cell processing because of its speed and ability to cut down on material waste, according to Carsten Busch Segment Manager Solar of ABB Robotics. In module production, ABB’s six axis robotics system sells well, due to its flexibility. “If companies are continuously innovating on form factor and recipes, free-programmable robots make this kind of innovation possible,” says Busch.
Driving the adoption of robotics is the need to increase the performance of processing equipment, better uptimes, and more wafers and modules processed per hour, according to Busch, who adds, “Anything they can do to reduce the TCO (total cost of ownership) to be more profitable and efficient is a high-priority. For us, that means high demand for materials handling robotics, but also robotics in process steps, and module assembly.”

The example of Solar Fabrik AG

As suggested above, the use of robotics and automation in module assembly is growing. A case in point comes from Solar Fabrik AG of Freiburg in Breisgau, Germany. It now runs three module manufacturing lines, with a total output of 130 megawatts. The first is “more or less manual”, according to Günter Weinberger, the company’s Chief Executive Officer. The latest, the third line, is a 60 MW “highly-automated” plant.
The main benefits, according to Weinberger, are higher throughput, increased reliability, less waste, and consistent quality of product. This is not to say that there is no human resources aspect in the use of automation. Finding workers to take on low-skill jobs is a challenge. And second, simple repetitive tasks are better done by robotics systems with their computer controlled belt drive mechanisms, unfailing grippers, precise motion ranges, and unblinking electronic “eyes” to avoid waste. “From a management perspective, you would expect low failure rates for simple tasks, but because the work is so boring for people, it is almost impossible to have no mistakes,” comments Weinberger.
Some labor cost reduction is an added benefit. Compared to line one, the newest line uses one-third of the workers per megawatt produced, according to Weinberger, but staff working on the line do require a higher level skill set, and they have responsibility for quality testing. In other words, wages are higher.
One thing that slowed down automation of module manufacturing until recently was the challenge to automate certain production steps, such as assembly of the junction box. The form factor of the j-box and the need for unthreading of the contacts did not lend itself to automation. Also preparing for this step meant opening up the backsheet before laminating, which risks contaminating the membrane, according to Paul Merz, General Manager Reis Robotics.
In the meantime, some module manufacturers designed their own junction box for automated assembly. Today, they are available off the shelf and companies like Reis Robotics, which was a key subcontractor of the aforementioned Solar Fabrik, are selling such solutions. The benefit of automation here is not subtle. It produces modules in a way that has less potential for damaged elements during assembly, meaning better yield and quality. “There is no manual action involved and possible cellbreak rates in this field are much reduced,” adds Merz.
According to Merz, there is global demand for his firm’s solutions. Reis Robotics claims 80 solutions installed worldwide able to produce 3.5 gigawatts. Most are in Europe, but a good 20 are in the U.S. and twelve in Asia. The reason the installed base in Asia is lower, according to Merz, is that the automated production started later. “But the Asian market is growing fast. Most new capacity is coming online there,” comments Merz.

Expansion promotes automation

The international expansion of some of the larger PV manufacturing companies in order to be closer to their markets is obviously a case that promotes advanced manufacturing technologies, even when they expand into lower labor cost countries. European and American companies create demand for automation equipment and solutions in Malaysia, Singapore and other low labor cost countries. The decision to automate then appears based on other reasons, as is made clear in a statement by Norway’s REC. It describes its new East Asian site as “one of the most integrated and automated in the industry”, giving two reasons for that: to ensure quality; and to achieve the goal of getting module costs to below one euro per watt.
Certainly, a new plant is expected to be more automated than older ones, but one of the benefits of manufacturing in lower labor cost countries is that there is potentially more flexibility in the degree of automation used. Theoretically, manufacturers could choose between more or less manual labor. The benefit is that one can hire and fire people to quickly cut costs if the demand for PV products declines. But that is not the case for companies like Q-cells, REC and First Solar, which have established plants in East Asia.
In an interview with Technology Business Review, Bernhard Rack, Executive Vice-President of Operations for Q-Cells Malaysia, was asked if lower labor cost was the main reason for the company’s decision to expand capacity in East Asia. He responded by explaining that “solar cell production is mostly automated, and the costs for fabrication and other equipments are relatively the same, so the difference in headcount costs does not make much of a difference.”
However, labor cost control could indeed be a factor for the decision to use more automation for the likes of Suntech Power Holdings of China as it expands module manufacturing into the U.S. to be near its market there. When Suntech unveiled its plans in January for Goodyear, Arizona, a plant that would initially have a 30 megawatt capacity, the company said it would be one that has the “latest manufacturing technologies”. That statement contrasts with what Suntech says about its China location. In its investor communication, Suntech says that in China it is “continuously striking a balance between automation and manual operations in manufacturing processes in order to optimize its cost structures, while improving manufacturing yields and quality”.
Geographic expansion is a driver of a global market for automation. So is the trend that sees the size and capacity of production plants increase. Fab size is evolving from typical fab capacities of 20 to 500 megawatts, even of one gigawatt. As factories get bigger, the need for automation increases. “There are multi-hundred megawatt module lines being built in Singapore and the U.S., all exhibiting a high degree of automation. If you have a 200 megawatt module line, you just cannot organize that in terms of manual labor,” asserts Reis Robotics’s Merz.

Better quality

The quest for ever greater crystalline cell-efficiency is an ongoing trend that continues to contribute to the demand for automation and robotics. In crystalline cell processing, these technologies are established in several front end processes, such as coating and patterning. “The automation is about running a process tool more precisely, accurately, and faster than any competing method of processing,” explains Vinay Shah of Applied Materials.
The list here of new tools and processes exhibiting automation, machine vision, and a range of robotics could be very long. Just one example that offers a case in point comes from Applied Materials. Its new Baccini Esatto back end screen printing tool uses sophisticated automation to carry out double printing on a narrower than usual first line. “The tool enables less shadowing to increase cell efficiency, but the printing must be very precise because alignment is critical,” Shah, Manager of new products crystalline explains. Since the solution improves cell efficiency, it goes without saying that the market for it is global. Indeed, one of the first customers to qualify that tool is Motech Solar, based in Tainan, Taiwan.

Room for improvement

A hurdle to using these technologies is a lack of common global standards for the range of automation and robotics in use in PV manufacturing today. As suggested, above automation is significant in several areas of wafer, cell and module production, including material handling equipment, gear that loads and unloads materials, linkage of process systems, such as screen printers and wet chemistry benches, as well as machine inspection systems. The thing is, many of the physical and logical components of automated manufacturing solutions have yet to be widely standardized. However, efforts are underway, such as those at SEMI where there are several activities directly related to automation. As an example, take the standard, PV2-0709 (commonly referred to as PV2). James Amano, Director of the SEMI Standards Program, says it defines a communication interface enabling shop floor IT systems and production equipment in the PV factory to talk to each other, as well as exchange and pass data, accordingly. He adds that other efforts, such as horizontal (equipment to equipment) communication and single substrate tracking, have strong industry support in Europe and Japan.
Other areas in which SEMI aims to get industry participation from around the globe include traceability of wafers and cells, to be able to isolate which part of a process was off, as well as standards for transport carriers. “There’s lots of potential for efficiency improvements for moving wafers and cells around the fab through automation and process integration,” says Amano.
Standardization can bring added benefits if the experience of other industries such as automotive and semiconductor manufacturing are anything to go by. “As it did for the integrated circuit industry, automation standardization will increase throughput, reduce equipment downtime, and lower costs,” states Amano.
Industry insiders agree. “Standardization could very well lower the cost of equipment. It will take some time, a mid-term time-frame,” comments Jonas & Redmann’s Spokesperson.
In the meantime, manufacturers are adopting automation and robotics to ensure better quality PV products. It is less about labor costs, and more about boosting quality and product performance. And it enables manufacturers to expand internationally in line with their corporate goals.

Automation and IT

Software is embedded in manufacturing tools and equipment for things like process control and monitoring, routing, tracking, and managing substrates and cassettes, storage and buffers. But systems tend to be proprietary. “There is some intertool automation standardization on communications interfaces,” comments Vinay Shah of Applied Materials, explaining that once there is a standard way of communicating and moving information around, more sophisticated applications can be linked in, enabling yield management, equipment performance monitoring and management maintenance schedulers.
One reason to explore this sort of automation, according to Shah, is that it is "less expensive to implement than physical automation." He adds that the cost benefit ratio is more apparent. As one example, he cited Trina Solar’s comments in a third quarter conference call with analysts last year, about how its manufacturing execution system (MES) gave it an advantage and had delivered shop floor efficiency improvements not long after installing the system.
Trina is not the only one to make such a move. Ads crying “help wanted” for solar industry engineers with MES experience in Singapore, China, Germany and the U.S., make that clear. So do installations announced by the likes of Camstar Systems, Eyelit and GE Fanuc.

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