Thickness loss, spin coating process

The most widely used technique for producing thin films of polymeric material is spin coating from solution. This technique is widely used in microelectronics fabrication to produce thin films of photoresist for photolithographic processes (Chapter 2). For this application, the thickness and uniformity of the photoresist must be accurately controlled, and to this end precision spin-coating machines have been developed offering accurate acceleration and spin speeds typically between 1000 and 10000revmin The requirement of polymeric thin films for optical purposes are very similar, and spin-coating techniques have been used to produce exceptionally low-loss structures [139]. 

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