Question $1(20$ marks$)$

The basic unit cell of the crystal structure shown below serves as the basic building block for cominnndurtare

$($a$)$ State the name of this crystal structure.

$[2$ marks$]$

$($b$)$ Explain the difference between the structure above and a zincblende structure.

$[4$ marks$]$

$($c$)$ Give an example of the semiconductor with zincblende structure.

$[2$ marks$]$

$($d$)$ Sketch the basic unit cell of the zincblende structure.

$[5$ marks$]$

$($e$)$ Given that the work function of silicon, $\backslash (\backslash$Phi $\backslash )$ is $4\mathrm{.}60$ eV $,$ determine:

$($i$)$ the cutoff wavelength.

$[3$ marks$]$

$($ii$)$ the maximum kinetic energy of the electrons in Joules

$($J$)$ when the silicon is irradiated with a wavelength of $200$ nm $.[4$ marks$]$