DIGITAL STORAGE DEVICE

摘要

A digital storage device comprises a crystalline substrate such as silicon in which pockets of amorphous substrate material represent one of the binary logic states; the absence of amorphous material represents the other logic state. The amorphous material is formed by irradiation with a laser beam. Typically the radiation for silicon is at 347 nanometres, 2.5 nanosecond pulse length. The power density varies with crystalline orientation; for (001) silicon it is typically 0.3 J/cm<2> and for (111) silicon it is 0.3 to 0.6 J/cm<2>. Erasure of the information is achieved by laser annealing the amorphous material back to its crystalline form.