Project Title:

Low-Scatter Silicon Optical Surfacing Using Plasma Assisted Chemical Etching

94-1		08.06	1667

Low-Scatter Silicon Optical Surfacing Using Plasma Assisted 
Chemical Etching

Abstract:

OCA proposes a research program into an improved, automated 
technology for the finishing of precision aspheric optical surfaces 
employing the Plasma Assisted Chemical Etching (PACE) process. 
Automated fabrication using the PACE process offers significant 
cost and performance benefits for the generation and finishing of 
low scatter, low subsurface damage optical surfaces on CVD silicon 
films on lightweight silicon carbide mirror substrates. The program 
will employ OCA's newly constructed PACE aspheric figuring system. 
Using this system and the new process, we will be capable of 
producing surfaces figured to precise tolerances with no physical 
surface contact and completely under computer numerical control. 
As part of the program, we will devise low sub-surface damage 
finishing processes for silicon, optimize the PACE process for Si-
SiC aspheric figuring and produce an aspherized Si-SiC 
demonstration optic to high-precision, low scatter optical 
tolerances. We believe that PACE will prove an efficient method for 
greatly reducing the cost of low-scatter aspheric optical 
components and will enable the greater use of aspheres in diverse, 
high-performance optical applications. 

OCA envisions several optical applications where the processes 
resulting from the proposed research can yield significant 
cost and performance advantages. These areas include ultra-low 
scatter optics, Si-SiC mirrors, zero sub-surface damage 
optics, inexpensive silicon aspheres, diamond films and 
complex oxide thinning and figuring. 

Key Words

OCA Applied Optics
7421 Orangewood Ave.,
Garden Grove, CA 92641