Nanometer-scale local oxidation of silicon using silicon nitride islands formed in the early stages of nitridation

Abstract

We have studied the silicon nitride (SiN) nucleation on the Si(111) 7×7 surface due to thermal nitridation with scanning tunneling microscopy (STM), and applied the resultant small SiN islands to oxidation masks in local oxidation of Si (LOCOS) process for fabrication of nanometer-scale Si structures. The nitrides appear as dark regions in STM images and the average size increases (the density decreases) with increasing nitridation temperature. When the nitrided surface is successively oxidized in the etching mode with a reaction of Si+O2→SiO↑, the nitrides turn to bright regions by selective etching of the clean 7×7 regions and the brightness (height) increases with increasing etching time. Thus, the microscopic LOCOS process is demonstrated and nanometer-scale Si pillars are fabricated.

Field electron emission device using silicon nanoprotrusions

“…Since the SiN islands again work as oxidation masks, Si protrusions can also be obtained by this oxidation, 6 although the grown SiO 2 must be removed by a HF solution at the final step. In this oxidation condition, SiO 2 film is grown on the Si surface.…”

Low-temperature formation of highly reliable silicon-nitride gate dielectrics with suppressed soft-breakdown phenomena for advanced complementary metal–oxide–semiconductor technology

“…6 Recently, using self-limiting atomic-layer deposition ͑ALD͒, 7-11 we developed a lowtemperature growth technique for silicon nitride. A high thermal budget in the formation process, such as thermal nitridation of silicon, 12,13 is not suitable for future gate dielectrics because it is difficult to obtain a precise doping profile.…”

Role of surface steps in the arrangement of silicon nano-dots on a vicinal Si(111) surface: Scanning tunneling microscopy investigation

“…Using lithography techniques, several groups have produced silicon pillars with diameters in the nanometer range. 9, 10 E-beam lithography technique is superior to the nonlithographic ones in fabricating the regular array of nanostructures, but it causes damage to the substrate due to its high beam energy. 7 Gas-surface chemical reactions can also be used for the formation of silicon nanostructures.…”