Thin-Wafer Silicon IGBT With Advanced Laser Annealing and Sintering Process

A novel insulated gate bipolar transistor (IGBT) featuring thin-wafer processing and a combined dopant activation laser annealing and contact metal laser sintering is presented. The device concept includes a new back-side boron anode (collector) activation process by laser annealing through a titanium layer to enhance the absorption of the deposited energy from the laser beam. This technology enables improved activation control of the anode injection efficiency for thin-wafer-based IGBTs rated normally below 1700 V. The IGBT concept will therefore be provided with a wider range of performance options on the loss technology curve when compared to state-of-the-art devices processed with conventional activation techniques.