Harvesting sunlight
If the roof of your house is decked out with solar panels, the Dutch company Tempress Systems has most likely been involved in their production. The company is the world's prime producer of the specialized furnaces needed to manufacture solar cells.
July 2013 year was exceptionally sunny for the Netherlands, a country not known for its hot summers. After a gloomy and chilly spring, many people gratefully took advantage of the sunshine to charge their batteries – both figuratively and literally, in the case of the growing number of people who use solar panels for at least part of their energy needs.
Solar panels – the basics
Solar panels consist of paper-thin silicon wafers with a layer of chemicals on top, which have the capacity to turn sunshine into electricity. The vaporised chemicals are deposited on the wafers in furnaces heated to a temperature of 950 degrees Celsius.
The main product of Tempress Systems is a horizontal diffusion furnace in which four batches of solar panels can be produced at once, thus enabling an output of some 1,000 wafers per hour. Each furnace consists of a gas chamber where vaporised gases are prepared, the actual furnace, a loading station and an automation unit.
Sandvik produces the heating cassettes
At the core of the machinery is the heating cassette, which provides the 950 degrees Celsius temperature required for the deposition process. It is a specialized piece of equipment that, like a car engine, determines the overall performance of the whole furnace. Some 30 years ago these heating cassettes were produced in-house by Tempress Systems, but in the early 1980s it was decided to outsource production.
Back then we made our own heating cassettes, but we didn't have the perfect equipment for it. We decided to purchase our cassettes from a real specialist in the field. That's when we found Kanthal in Germany", Jaap Fidom, material manager at Tempress Systems, recalls.
Kanthal was an established producer of heating elements for furnaces for a variety of industries, ranging from steel production to dentures. In 1997 the company was taken over by Sandvik and incorporated into Sandvik Materials Technology and its product area Wire and Heating Technology. The advanced products of Kanthal remained on the market under their own name however and the takeover resulted in important synergies in the field of materials technology.
Advanced metals from Sandvik
"We were able to greatly improve the most decisive feature of our heating cassettes, which is the wire. By using Sandvik's most advanced heating alloys, we could produce a heating cassette that outperformed all other solutions in the industry, in terms of efficiency and lifespan", says Stefan Schatz, managing director of Sandvik Materials Technology, Germany.
The unparalleled performance of the wire was one reason why Tempress Systems selected Kanthal heating cassettes for its furnaces.
"We have become a global market leader because our furnaces excel in the field of process reliability and efficiency. The Kanthal heating cassettes perform better than those of any other brand.", says Jaap Fidom
Delivery time and service are crucial
A particular selling point for Tempress Systems is the quick delivery time and efficient aftersales service that it provides to customers, most of whom are situated in Asia. The cooperation between Tempress Systems and Sandvik has turned out to be a success for both, greatly exceeding normal client-supplier relationships.
"We share a lot of R&D regarding the heaters. We can provide feedback about their performance and make suggestions for improvement, which Sandvik with its expertise can then turn into practical solutions. Conversely, Sandvik is eager to use our test facilities to try out innovations. This way we have built up some unique know-how, which is exclusively applied in our furnaces", Jaap Fidom concludes.
Solar power is a hot topic in any discussion about energy and the environment. In a world increasingly worried about its own energy needs, solar panels provide one of the most elegant solutions currently available. As long as the sun shines, mankind has the potential to tap this inexhaustible supply of clean energy.
The challenge: Wire is the active part of the heating element. Its metallurgical properties determine its performance. Tempress Systems did not have the expertise or the equipment to produce wire.
The solution: Sandvik produces heating wire that makes it possible to develop a heating cassette that excels in terms of process reliability, energy savings and lifespan, largely thanks to the unique metallurgical formula of the heating alloy.
The results: The collaboration with Sandvik has helped Tempress Systems to become a world market leader in its field.
Facts about Tempress Systems
Tempress Systems is a producer of vertical and horizontal diffusion and LPCVD furnaces for the production of semiconductors and solar cells. The company was started in 1967 and is a subsidiary of Amtech Systems Inc. It is located in Vaassen, the Netherlands.Tempress has a workforce of 120 employees. The company produces several furnaces a week, mainly for the solar industry.