Cleanroom builds in the 'silicon valley'

Scholpp Montagetechnik Sachsen is currently completing an extensive cleanroom move-in project. It started back in May 2003 with the implementation of construction site logistics and will end in late June with the successful completion of one of the most modern 300mm wafer fabrications in the world. For Scholpp, the commission to move in all the tools as the sole rigging company was another in a series of large-scale projects in the sector of cleanroom move-in within a short period of time. Projects on a comparable scale have been realised and are presently being undertaken by AMD FAB 30, 1st Silicon Malaysia, Texas Instruments Freising, Philips Semiconductor Hamburg and AMD FAB 36.

Construction phases Primarily by order of the general contractor M+W Zander (Stuttgart), the Scholpp key team organised the move-in of the extensive, highly sensitive special machinery. The machines will be operated at the new e400m Siltronic production site opened in June 2004, where 300mm pure silicon wafers will be manufactured and processed. In all phases of transporting, moving in and commissioning the production machines for cutting, grinding, etching and polishing – some of which cost up to e2.8m – severe safety regulations and cleanroom conditions were observed. Siltronic, part of the Wacker group, is one of the market leaders in the field of wafer fabrication and a partner to many leading chip manufacturers. Silicon wafers are the basis for highly complex electronic components produced by the semiconductor industry. Under the motto 'perfect silicon solutions', the indispensable basic products for modern micro- and nanotechnology are fabricated in Freiberg, to be used in items including computers, mobile phones, internet technology, DVD players, flat screens, navigation systems, airbags, computer topography, and aeroplane control systems. As a top three member of the global wafer sector, Siltronic is active in a value-added network with five state-of-the-art fabrication sites and numerous production lines in Europe, Asia, Japan, and the US. The new fabrication centre in Freiberg, one of the most advanced sites worldwide, is situated very close to Dresden, an important European microelectronics centre. The site boasts high-tech production lines for wafers and a top-of-the-range crucible pulling plant for silicon crystals. With the construction of the new fabrication line Fab-300 for the future-oriented 300mm wafers, Siltronic is expanding its market position in this growth sector. On highly pure silicon wafers, increasingly fine nanostructures are being realised. The larger the wafer diameter, the higher the yield for the processor or memory circuit producer – to the advantage of their economic efficiency. The Scholpp move-in project is headed by project manager Hans-Peter Klein and site manager Lothar Domke. After winning a demanding tendering process defined by severe requirement and efficiency criteria, Scholpp started the job by tackling the extensive preparatory measures. The wide range of services provided by the Scholpp cleanroom move-in key team comprises not only the work done in front of and inside the cleanroom, but also in the 'base building' phase, where the specialists deal with tasks that are a precondition for erecting the shell of the cleanroom, including the construction of the technical systems. Here, Scholpp was commissioned to move in the transformers, compressors, containers, filter presses and ventilation systems. Setting up an interim storage location for all companies working on the construction site helped to manage the complex building site logistics, and Scholpp organised the central provision of cranes, fork-lift trucks, special equipment, and assembly teams on the building site for support of the subcontractors, and to limit the rental costs they incurred. Direct contact While two men were enough at the start, Scholpp had to assign up to 24 fully qualified cleanroom move-in specialists during the peak phases of this extensive project. To ensure organisation of the single process steps in direct contact with the project, the Scholpp team set up shop in the container village right outside the gates of the Freiberg Siltronic Fab. Scholpp project manager Hans-Peter Klein said: 'First, Siltronic gave our team an intensive introductory course, including cleanroom training. As the machines were arriving at irregular intervals, we needed to draw up a flexible schedule to adjust the time and staff requirements for the respective machine delivery and to optimise the disposition of necessary machinery. 'For this kind of project, it is very important to have key personnel who know the machines and the location and who know how to build good relations with the client, the end customer, and the other companies involved in the project. 'This creates trust, helps to ensure the safety necessary in all processes, and saves time and – last but not least – money. For a smooth work flow, it is important to co-ordinate the flow of tools, the availability of equipment and staff, and the time needed for cleaning and move-in.' The strict cleanroom protocol specifying the conditions to be met even before entry into the cleanroom requires thorough cleaning of each tool before it is moved in, the cleaning results to be evidenced by particle measurement on the surface. 'To prepare to transport, Scholpp covered the cleanroom floor with stainless steel plates to protect the sensitive double floors,' explained Klein. 'The air cushion systems used for shock-free transport are fed with filtered pressurised air from compressors mounted on car trailers. The aluminum portals developed at Scholpp for lifting and mounting machine components have a special aluminium alloy finish. They are extremely stable, easy to transport, and primarily easy to clean.'

Traditional projects Scholpp site manager Lothar Domke commented: 'Contrary to traditional move-in projects where the weights to be lifted and time needed are the primary criteria, the requirements for cleanroom move-in projects are clearly different. The only important factor is to safely unload and transport the boxes equipped with shock sensors, and to transport the tool elements safely and without any damage to their intended location, while observing the cleanroom protocol. 'This requires the competence of an extremely well qualified team. The components for the valuable machines arrive in instalments and were assembled in the cleanroom. The Scholpp cleanroom move-in team is made up of fitters who not only transport components, but use their experience and equipment to support the machine manufacturers during set-up of the plants. 'A process machine weighing 12 tons is, for example, made up of components delivered in 28 boxes, some of these lighter than the crane hook. In individual phases, parts of the tool are moved into the production building via different paths. Because of the cleanroom protocol and the various work stations during unloading, transport outside of and within the cleanroom and the respective transfer of the components in the cleanroom lock, and finally helping the machine manufacturer during assembly, move-in projects are very labour-intensive and require much co-ordination.'

Continuing investment Thanks to its long years of experience within the Scholpp group, in a short time the Scholpp Group responsible for cleanroom move-in has managed to become a fixture in the market segment of cleanroom operators. Uncompromising expansion and continuous investment in equipment and staff resulted in quick growth of the establishment. In the course of the development, additional service points have been set up, for example in Dresden, a centre for nanotechnology. Today, Scholpp'scentre of competence has 60 specially qualified staff dedicated to cleanroom equipment. Considering the value of the assets to be moved, and the risk of a loss of production, an increasing number of operators and machine manufacturers commission competent specialists to minimise their risks. To save costs, the full logistics package is awarded to specialist companies like Scholpp as a part of the total contract. Today, Scholpp's cleanroom move-in competence centre team serves a highly demanding clientele, from the special forwarder to the tool manufacturer, Fab operator, general contractor and planner.