SPARK-PROCESSING - A NOVEL TECHNIQUE TO PREPARE LIGHT-EMITTING, NANOCRYSTALLINE SILICON

The properties of spark-processed Si appear quite promising for applic ations like optically active components. Spark-processed Si photolumin esces strongly in the violet and in the green spectral range (dependen t on processing). The response is fast (nanoseconds), and its stabilit y against HF etching, intense laser irradiation, and annealing is rema rkable. The microstructure reveals nanocrystalline Si particles which are imbedded in an amorphous matrix. An unambiguous link between these nanocrystals and photoluminescence has not been established. However, several other proposed mechanisms can be excluded based on experiment al evidence.