Memory Characteristics of Metal-Oxide-Semiconductor Structures Based on Ge Nanoclusters-Embedded GeO _x Films Grown at Low Temperature

The memory devices constructed from the Ge-nanoclusters embedded GeO _x layer deposited by the laser-assisted chemical vapor deposition (LACVD) system were fabricated. The Ge nanoclus-ters were observed by a high-resolution transmission electron microscopy. Using the capacitance versus voltage (G–V) and the conductance versus voltage (G–V) characteristics measured under various frequencies, the memory effect observed in the G–V curves was dominantly attributed to the charge storage in the Ge nanoclusters. Furthermore, the defects existed in the deposited film and the interface states were insignificant to the memory performances. Capacitance versus time (G–t) measurement was also executed to evaluate the charge retention characteristics. The charge storage and retention behaviors of the devices demonstrated that the Ge nanoclusters grown by the LACVD system at low temperature are promising for memory device applications.