A method for evaporating silicon to form low dimensional Si lattice structures

Physical deposition by evaporation is a convenient and cost effective method for generating thin layers of material. In this work, we utilise an electron-beam evaporation system retrofitted with a rotating shutter to control and reduce the deposition rate of materials. Under normal conditions, the evaporator is able to achieve a typical deposition rate of 1 A/s. In order to reduce the deposition rate, a rotating shutter was designed and retrofitted to the evaporator. The rotating shutter consists of a metal plate with a slit opening of 6° and 36°. When rotated during evaporation, a reduction in deposition rate of 1/60 and 1/10 onto a sample is expected. We can control the deposition to achieve a rate of 1 A/min. By using this modified system, we deposited Si and SiO₂ onto Si substrates. In situ deposition is monitored using a quartz thickness monitor. After evaporation, film thickness is measured using AFM and verified with spectroscopic ellipsometer measurement. Using this method, we are able to reach a deposited film thickness of 3 nm. This work is expected to contribute significantly towards the fabrication of low dimensional silicon devices.