Question

After spinning of photo resist over a wafer with prefabricated microstructures that introduce certain topology (i.e. non-flat surface) as shown bellow. Given the fact a g-line UV light exposure system with 257nm wavelength (i.e. λ=257nm).Based on your best scientific judgment (i.e. hand calculation with calculator), will the grating patterns in Region A come out after a standard photolithography? (Go ahead assume the rest of the photolithography steps are perfectly done) (15 Pts).How about the similar grating patterns in Region B? Will those patterns in Region B turn out to be good after standard photolithography process? (Please support your conclusion with calculations) (15 Pts)

A: 405 nm cline) Gap) Sum SiNon Substrate Region A Regian B ιση

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Answer 1

After spinning of photo resist over a wafer with prefabricated microstructures that introduce certain topology (i.e non-flat surface) as shown below. give the flat a g-line uv light exposure systems with 257 nm wavelength i.e. lambda = 257 nm the silicon surface is easier to be etched than the surface & etching speed depending on the crystal axis the difference creates the saw-edged structures. Blaze angle can be obtained by tilting the surface the wafer surface. Transport materials are required for high throughout optical system the materials heavily limited in the MIR region. \r\n silicon germanium CSI, KRs - 5', diamond here CSI is deliquescent kRS - 5 has toxicity AR is multi-layer interference coating, but it has two issues in wavelength regions. 1^st one is various optical material. the coating consists of some layers of the transport material with different refractive indices the mask pattern is drawn on a curved surface deformation occurs due to the