Mumbai University > Electronics Engineering > Sem 8 > MEMS Technology

Marks: 2M

Often, lithographic patterns on both sides of a wafer need to be aligned with respect to each other with high accuracy. E.g. the fabrication of commercial pressure sensor entails forming on the front side of the wafer piezoresistive sense elements that are aligned to the edges of a cavity on the back side of the wafer.

Different, methods of front-to-back side alignment, also known as doubly sided alignment, have been commercially available tools.

Wafer polished on both sides should be used to minimize light scattering during lithography.