Ge Nanocrystals Metal-Oxide-Semiconductor Capacitors with Ge Nanocrystals Formed by Oxidation of Poly-Si0.88Ge0.12

In this paper, we report a simple and CMOS compatible method for forming Ge QDs using selective oxidation of SiGe and demonstrated significant memory effects in the related Ge nc metal-oxide-semiconductor capacitors (MOS-Cs). It is known that Si is preferentially oxidized during high-temperature oxidation of SiGe alloy and the Ge segregation, induce Ge atom pile-up along the SiGe/SiO₂ interface. Therefore, Ge QDs would be naturally formed by Ge atom segregation and agglomeration. Besides, Ge QDs would be more attractive for nc transistors because that stronger carrier confinements and larger energy level separations (smaller tunneling noise) would be achieved for their lower energy bandgap and smaller carrier´s effective mass as compared to Si QDs with the same size. It is reasonable to expect that Ge nc memory devices would provide better solutions for the trade-off between speed and retention time