$1).$ Device Design Constraints

When designing a reduced dimension n$-$MOSFET, the following device design parameters are considered:

$($i$)$ Channel length $($L$).$

$($ii$)$ device isolation $($LOCOS$).$

$($iii$)$ New gate dielectric materials $($Eox$).$

$($iv$)$ source$/$drain junction profile.

$($v$)\backslash (\backslash$mathrm$\{$N$\}+\backslash )$ polysilicon gate

Determine their effects on $($i$)$ the drain current ld at saturation region $($ie$.$ Vg $\backslash (=\backslash$mathrm$\{$Vd$\}>\backslash$mathrm$\{$Vt$\}\backslash )).($ii$)$ the subthreshold current ldst$,($iii$)$ the device threshold voltage $($Vt$).($iv$)$ the hot carrier substrate current $($lsub$).$ and $($v$)$ the drain induced barrier lowering $($DIBL$)$

Characteristics

$\backslash$begin$\{$tabular$\}\{|$l$|$l$|$l$|$l$|$l$|$l$|\}$

$\backslash$hline Parameters & Id & ldst & Vt & lsub & DIBL $\backslash \backslash$

$\backslash$hline $\backslash$begin$\{$tabular$\}\{$l$\}$

Shorter channel length $\backslash \backslash$

$($L$)$

$\backslash$end$\{$tabular$\}$ & & & & & $\backslash \backslash$

$\backslash$hline $\backslash$begin$\{$tabular$\}\{$l$\}$

Shallow trench isolation $\backslash \backslash$

$($STI$)$

$\backslash$end$\{$tabular$\}$ & & & & & $\backslash \backslash$

$\backslash$hline High K dlelectric materlals & & & & & $\backslash \backslash$

$\backslash$hline $\backslash$begin$\{$tabular$\}\{$l$\}$

pouble diffused drain $\backslash \backslash$

junction $($DDD$)$

$\backslash$end$\{$tabular$\}$ & & & & & $\backslash \backslash$

$\backslash$hline $\backslash$begin$\{$tabular$\}\{$l$\}$

Tungsten $($W$)$ gate $\backslash \backslash$

material

$\backslash$end$\{$tabular$\}$ & & & & & $\backslash \backslash$

$\backslash$hline

$\backslash$end$\{$tabular$\}$

Describe the assumption you use in answer the questions and Fill in answers with the following symbols:

increase

decrease

unchanged