Implementation of a Comprehensive On-Line Closed-Loop Diagnostic System for Roll-to-Roll Amorphous Silicon Solar Cell Production: Phase I Annual Report, 23 April 2003--31 August 2003

This subcontract report describes how Energy Conversion Devices, Inc., has developed and built 7 generations of roll-to-roll amorphous silicon PV production equipment. In the ECD/United Solar production process, we deposit about a 1-mm-thick, 12-layer coating consisting of a metal/oxide backreflector, a 9-layer a-Si/a-SiGe alloy triple-junction solar cell, and top transparent conductive oxidecoating onto 125-mm-thick, 35.5-cm-wide stainless-steel webs in a series of three roll-to-roll deposition machines. In the PV Manufacturing R&D 6 program, ECD is building upon these accomplishments to enhance the operation of the present production machine, and lay the foundation for improvements in the next-generation machine. ECD has completed the Phase I work for the first two Tasks, and willcomplete the Phase I work for the second two tasks within the next two months. In the following report, we summarize the Phase I work in each of these tasks. We have involved United Solar production personnel in each of these Tasks. This is important for two reasons: First, the collaboration of ECD and United Solar personnel keeps the projects responsive to the developing needs at United Solar;and most of the tasks affect operations and consequently need the support of United Solar production and QA/QC managers. In the process we have developed a good working relationship between the production personnel, whose mantra is 'change nothing,' and the R&D personnel, who mantra is 'change everything.'