Multipin ac corona treatment - a new surface activation method for low temperature direct bonding

A multipin AC corona discharge at atmospheric pressure is introduced as a new method for the activation of silicon wafers, leading to high bond strength on the annealing temperature range between 200 °C and 400 °C. The main advantage of corona treatment is related to the spatial separation of the plasma zone and the wafer, hence reducing the electric field stress at the wafer surface.