A new method of fabricating multilayer optical coatings used at terahertz frequencies has been developed. Using plasma-enhanced chemical-vapor deposition, a multilayer antireflection coating for germanium optics at terahertz frequencies was fabricated. The coating consists of amorphous silicon and silicon-oxide layers. The transmittance and structure of the coating were experimentally investigated. The transmittance spectrum of the coating on the Ge substrate shows a wideband antireflection behavior in the 40–120 cm−1 region.
© 2005 Optical Society of America
Original Manuscript: March 22, 2004
Revised Manuscript: December 20, 2004
Manuscript Accepted: January 20, 2005
Published: June 20, 2005
Iwao Hosako, "Multilayer optical thin films for use at terahertz frequencies: method of fabrication," Appl. Opt. 44, 3769-3773 (2005)