Question

The mobility and carrier density of Al are 12 cm2/Vs and 1.98×1023 cm−3 , respectively. The mobility and carrier density of Cu are 43.2 cm2/Vs and 8.5×1022 cm−3 , respectively. [20 pts] Q3.1 Calculate the resisitivity of Al and Cu Q3.2 Which one would you use as interconnects in advanced CMOS nod

Answer 1

Answer:

R aluminium = 2.63x10^-6 Ω*cm

Rcopper = 1.7 x10^-6 Ω*cm

I would use Cu as interconnections in advanced CMOS nodes.

Explanation:

the conductivity formula equals:

σ = n*g*u

n = carrier concentration

u = mobility

g = charge of carrier

The resistivity is equal to:

R = 1/σ

For the aluminium, we have:

g = 1.602x10^-19 C

R = 1/(1.98x10^23 * 1.602x10^-19 * 12 = 2.63x10^-6 Ω*cm

For copper:

R = 1/(8.5x10^22 * 1.602x10^-19 * 43.2) = 1.7 x10^-6 Ω*cm

According to the calculations found for both resistivities, I would use Cu as interconnections in advanced CMOS nodes, since copper has a lower resistivity and therefore, copper conducts electricity better.