Power semi packaging breakthrough
Power semiconductor specialist Semikron has developed a new packaging technology which is said to remove the need for bond wires, solders and thermal paste. Called SKiN technology, the approach is based on the use of a flexible foil and sintered connections.
According to the company, current density is doubled to 3A/cm^2 and converter volume is reduced by 35%. In addition to removing the need for wire bonding, a sinter layer is used to replace solder thermal paste, said to be responsible for 30% of the total thermal resistance in a system.
This means thermal conductivity between chip and heat sink is improved, resulting in a 30% increase in usable electric current. Alongside higher current carrying capacity, devices constructed using this technology are said to have ten times the load cycle capability of wire bonded parts.
Semikron says wire bonding has been the main method of connecting the chip's top side to a direct bonded copper substrate for 25 years, but notes this method cannot meet support higher current densities.
