Formation of nanometer silicon dots with germanium core by highly-selective low-pressure chemical vapor deposition

Nanometer dots with a stacked Si/Ge structure are attracting attention because of their potential importance for precise control of the carrier confinement. To date, the island formation of Ge at an expected position on Si(100) and the overgrowth of Ge on Si islands have been reported. And we have studied the self-assembling of nanometer Si dots on SiO/sub 2/ by controlling the early stages of LPCVD of monosilane and demonstrated the positioning and arrangement of Si dots on SiO/sub 2/ with the control of nucleation or reactive sites such as surface OH-bonds. In this work, we have extended our research to the formation of silicon dots with Ge core by alternately controlling the selective growth conditions in LPCVD using pure SiH/sub 4/ and GeH/sub 4/.