Synthesis of ultrathin heteroepitaxial 3C-SiC films by pyrolysis of molecular layer deposition polyamide films on Si

Abstract

Polyamide films were grown on Si(111) using a molecular layer deposition (MLD) process with 1,2-ethylenediamine and trimesoyl chloride precursors at 120 °C. Synthesized polyamide films on Si(111) were then pyrolyzed in vacuum (10−7 Torr) to yield crystalline SiC thin films. High-resolution transmission electron microscope images of heat-treated samples showed the heteroepitaxial nature of the synthesized 3C-SiC (β-SiC) with respect to the Si(111) substrate. Raman, x-ray photoelectron spectroscopy, and x-ray diffraction analysis confirmed the formation of single-crystal SiC films. Samples pyrolyzed at 1300 °C showed defects attributed to Si sublimation. Formation of highly conformal SiC film after pyrolysis was demonstrated using Bosch-processed Si trenches. The thicknesses of 3C-SiC films obtained after pyrolysis were linearly dependent on the number of MLD cycles used to deposit polyamide films.