Backside metallization is required for many high performance applications like power devices, microprocessors, laser diodes where backside contacts are needed for subsequent die attach. Precise control of pre-clean and deposition processes is very important for excellent thermal, electrical and mechanical properties. This process is sometimes done on very thin and fragile wafers, so ability to control stress and handling the wafers is very critical.

N2 flow during deposition improves film stress. N2 flow during deposition decreases film stress from highly tensile to almost zero stress. Ti or TiW adhesion layer improves film stress.

Tango offers process recipes for very low, and even zero stress on common material stacks used for backside metallization.

  • Common Film Stacks: Ti/Pt/AuSn, Ti(W)/Au, Ti/Ni(V)/Ag
  • Wafer flipping option for 200/300mm
  • Wafer front side protection
  • Ability to handle warped wafers as well as Taiko wafers
  • Taiko processed wafers to 30 microns

Backside Metallization

  • HPC (IGBT)
  • HBM (IGBT)
  • Power electronics (IGBT)
  • Ability to Handle wafers on Edge
  • Prevent Front side contact to Hard surfaces
  • Flipping with Bernoulli
  • Stress optimization for thick layers