Why Diamond and semiconductor material like Silicon are used in electronic industry as heat sink. What make them so special? Solution In electronic industry diamond is used as heat sink material, due to its high thermal conductivity of 2000 W/mK. Heat is conducted by lattice vibrations in diamond,which provides very high thermal conductivity. In electronic industry, silicon is widely used as material for thermal grease, due to its high electrically insulating property but thermally conductive in nature.It acts as heat transfer medium from component to heat sink. Silicon also provides excellent protection against moisture. Silicon is non-setting in nature, it facilitates easy replacement of component, without damaging component and heat sink..