Material Requirements for PV Applications

In this section we discuss first the general materials requirements for an absorber layer. Specific issues for particular materials are then considered in subsequent sections. The specific optoelectronic properties of each absorber layer will not be 

For use in PV devices, the absorber layer must be uniform laterally on both the micrometer and centimeter length scales with respect to its composition, and vertically on the micrometer length scale with respect to its thickness. Lateral uniformity on the centimeter scale is a prerequisite for fabrication of larger area PV devices, and the vertical thickness needs to be uniform in order to avoid stress in subsequent deposited layers and to avoid pinhole formation. A final criterion to consider is that the absorber layer must adhere well to the substrate so that it can withstand subsequent thermal treatment. 

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