Control of sizes and optical emission of SiGe quantum dots prepared on ordered mesoporous silica coated Si wafer

A new way of preparing wafer sized SiGe and Ge quantum dots at extremely low cost is presented. The results show that two different controlled nanometer sizes of the quantum dots can be formed simultaneously into two layers on the same wafer with good dot size uniformity. Our initial experiments on SiGe and Ge system suggest that it is possible to squeeze the SiGe dots for much improved optical emission. The advantages of this dot preparation method are its fully compatibility with the Si-technology, its simplicity in dot preparation and extremely low cost.