Three dimensional integrated circuits

摘要

Semiconductor crystal grains are formed by metal-induced lateral crystallisation. The positions of the grain boundaries normal to the crystallisation direction are controlled, to position the grains correctly for subsequent formation of electronic devices within them. In a first technique, the grains are positioned by depositing the metal in short strips which each induce the crystallisation of a single corresponding grain. In a second technique, the grains are positioned by pre-patterning the amorphous silicon which is used to form the grains. Electronic circuit elements can be formed in each grain. The resultant structure can be used in a microelectronic mechanical system. Several grains can be formed successively and circuit elements formed in each layer to form a three-dimensional integrated circuit.