Routes to Novel Dielectric and Semiconductor Devices Using Cyclohexasilane

Abstract

A newly developed “liquid silicon” precursor will be discussed. Cyclohexasilane (CHS; Si6H12) has been used to make silicon-based films (such as polysilicon, silicon nitride, silicon carbide and others), as well as silicon nanowires and quantum dots. CHS offers a more versatile, lower-cost and safer pathway to a variety of silicon based products being considered for flexible and printable electronics.There is a need for a silicon precursor that is not only cost effective, but one that can be readily chemically functionalized to develop advanced materials. CHS is one such silicon precursor that is a liquid at room temperature allowing for easier storage and handling. Cyclohexasilane has a moderate boiling point, 80 °C at 15 torr. It has long been considered to be the preeminent silicon precursor for a variety of applications including semiconductor devices and can create thin films of β-SiC on a variety of substrates under mild conditions including conventional CVD; but also LPCVD, APCVD, and laser assisted CVD. The growth rate of β-SiC using CHS is an order of magnitude faster compared to other silicon precursors and the crystalline quality should rival materials grown by MBE.Aside from those advantages, CHS allows for facile p-doping of materials into the β-SiC films such as aluminum and due to the methods of deposition and the deposition conditions amenable to a reagent such as CHS, continuous growth with the suppression of unintentional secondary deposits may be readily achieved. Moreover, it may be possible to use CHS to achieve solution growth to deliver high structural quality SiC with significantly decreased capital and operational costs.The use of CHS across a wide range of industries and applications will be discussed as will the advantages of this material over incumbent technologies.