Fabrication of silicon-on-SiO2/diamondlike-carbon dual insulator using ion cutting and mitigation of self-heating effects

A diamondlike-carbon (DLC) layer was used to substitute for the buried SiO2 layer in silicon on insulator (SOI) to mitigate the self-heating effects in our previous study. However, we discovered drawbacks associated with the inferior Si/DLC interface, inadequate thermal stability as well as carbon-silicon interdiffusion at the Si/DLC interface that could hamper future application of this silicon-on-diamond structure to microelectronic devices. In this work, we introduced a silicon dioxide barrier layer between the Si film and DLC buried layer to form a silicon-on-SiO2∕DLC dual-insulator structure to tackle these problems. Cross-sectional high-resolution transmission electron microscopy reveals that the Si/insulator interface is atomically flat and the top Si layer has nearly perfect crystalline quality. The SiO2∕DLC dual-insulator layer retains excellent insulating properties at typical complementary metal oxide silicon processing temperatures. Numerical simulation reveals that the negative differential resistance and channel temperature are significantly reduced compared with those of the same metal oxide semiconductor field effect transistors fabricated in conventional SiO2-based SOI, suggesting that the silicon-on-dual-insulator structure can alleviate the self-heating penalty effectively.