Q$3($a$)$ Discuss the following lithography methods. $($a$)$ X$-$ray lithography $($b$)$ E$-$beam

lithography

$($b$)$ Discuss in detail the need of the actuators and the type of the actuators typically used for the active optical MEMS applications using suitable diagrams.

Q$4($a$)$ Discuss in detail about the PECVD technique for thin film deposition with neat

schematic diagram.

$($b$)$ What is the role of a photomask in a typical photolithography process? How are photomasks prepared?

Q$5($a$)$ Describe the Young's modulus $($E$),$ Bulk modulus $($K$),$ Shear modulus $($G$)$ and

Poisson's ratio and discuss about their relationship.

$($b$)$ Explain in detail about the basic modeling elements of a mechanical elements with necessary equations and diagrams.

Q$6$ Write short answer on following:

$(8$x$2)$

$($a$)$ LIGA.

$($b$)$ MEMS micromirror.