Extreme Ultraviolet Lithography (EUV) is being developed as a next-generation photolithography tool in the semiconductor manufacturing industry. Because the wavelength of light proposed for EUV can be as short as 14 nm, reflective (rather than transmissive) optics must be used.

(a) Why is this true?

(b) If 11 reflections are needed in order to project the image onto the wafer (including the reflective mask pattern), what is the minimum reflectance of all of the mirrors in order for 90% of the light from the source to strike the photoresist on the wafer?

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Please provide detailed explanation in text format