We develop a downstream localized plasma-etching process that permits in situ monitoring of light throughput in a semiconductor-clad channel waveguide as the semiconductor thickness is trimmed. Hydrogenated amorphous silicon films are deposited on ion-exchanged channel waveguides by plasma-enhanced chemical vapor deposition. We then employ the localized plasma-etching process to maximize accurately the extinction ratio between TE and TM polarizations propagating in the clad waveguide. We achieve polarization extinction ratios of greater than 30 dB for both TE-pass and TM-pass polarizers.
© 1994 Optical Society of America
Original Manuscript: December 29, 1992
Revised Manuscript: July 9, 1993
Published: March 1, 1994
David L. Veasey, Donald R. Larson, and Iris Veigl, "Waveguide polarizers processed by localized plasma etching," Appl. Opt. 33, 1242-1244 (1994)