Short-pulse Laser Crystallization And Structuring Of A-ge

Laser pulses in the nanosecond range were used to crystallize and structure (lateral dimensions≤1 μm) amorphous germanium thin films. The crystallized material consists of grains with sizes increasing from about 5 to more than 20 nm as a function of laser pulse energy. Arrays of polycrystalline Ge dots (diameter ∼1 μm, period ∼5 μm) were produced by bringing three laser beams to interference on the sample surface. These arrays can be used as seeds for solid-phase growth of polycrystalline areas by thermal annealing below 450°C.