Nutrient Cycling and Recycling Within Periphyton Communities

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9871253 Mastrangelo In this proposal the PIs request funds to purchase a new replacement for their mask maker machine at the University of Michigan Solid-State Laboratory. Their ASET machine was donated by Ford Motor Company in January of 1993. Since it was installed in their lab, this machine has served more than one hundred of users, both internal and external to the Solid-State Laboratory, and it has become an essential piece of equipment. Currently, this machine serves 37 regular qualified student operators serving more than 110 students, with an annual usage of 250 mask plates per year. Since 1993, approximately 1000 lithographic mask plates have been made in this machine in support of as many as 200 different student projects from more than 1O different faculty members. Photolithographic masks are essential for solid state device work. Typically, as many as 20 masks per student per year are required. Externally, each of these costs between $400-$600. With our existent system each mask is made at a cost of $50. Approximately 250 masks are made per year by the UM faculty resulting in roughly $90,000 of savings per year. The high cost of mask making is a definite limiting factor in the research performed at the Solid-State lab, and their system has served them well in reducing these costs. While still useful, the current mask making machine is a 1986 model, and it is difficult to repair. Its controlling computer and associated boards have chips no longer manufactured. The lack of parts is a serious concern. Further, its mechanical parts already show signs of wear. Therefore, they believe that this machine will soon no longer be supportable. This will have a major impact in all the research projects that utilize the machine, and unless this situation is remedied, the overall laboratory output will drop substantially. Therefore, they must request funds to replace their system. The replacement of our system has a cost of $695,300 (options 1,2, and 4 included).While expensive, a new machine has slightly better optical resolution that the older system, but it has completely new mechanical parts therefore a much greater reliability. The die size will remain at its current large size (2 cm) at the expense of resolution (1.1 um) because most of our sensor and MEMS projects need the large die capability (mask makers with finer resolution cannot project over these large dies). ***