Chapter 50
Material properties
Several materials are commonly used in integrated circuits. These materials are mainly silicon, and silicon dioxide. Other materials of interest are mold compound, and FR4 epoxy as they are in the immediate environment of ICs.
50.1 Electrical data
50.1.1 Silicon
Silicon is the most widely used material inside ICs. All components but true capacitors are built from silicon.
50.1.1.1 Dielectric constant
ϵ R=12.9
50.1.1.2 Carriers Mobility
In semiconductors, two types of carriers exist.
50.1.1.3 Resistivity
50.1.1.4 Breakdown electrical field
50.1.2 Silicon dioxide
Silicon oxide is probably the most used material after silicon in ICs. Capacitors are built from metal and oxide and the dielectric layers between connection layers are made from oxide.
50.1.2.1 Dielectric constant
ϵ R=3.9
50.1.2.2 Breakdown electrical field
EB=10^9V/m
50.1.3 Silicon nitride
Silicon nitride is used as a passivation layer over the metal stack and final oxide.
50.1.3.1 Dielectric constant
ϵ R=7.5
50.1.3.2 Breakdown electrical field
EB=V/m
50.1.4 Mold compound
Mold compound is the material surrounding silicon in molded plastic packaged ICs.
50.1.4.1 Dielectric constant
ϵ R=
50.1.4.2 Breakdown electrical field
EB=V/m
50.1.5 FR4 epoxy
PCBs, often made from FR4 material are the ICs environment outside the package.
50.1.5.1 Dielectric constant
ϵ R=4.35
50.1.5.2 Breakdown electrical field
EB=V/m
50.2 Thermal data
50.2.1 Silicon
50.2.1.1 Thermal conductivity
149 W/(m.K)
50.2.1.2 Thermal coefficient of expansion
50.2.1.3 Specific heat
50.2.2 Silicon dioxide
50.2.2.1 Thermal conductivity
1.4 W/(m.K)