Dalsa Semiconductor Inc.

Jonathan Lachance

Luc M Ouellet

Stephane Blain

Sylvie Archambault

Manuel Grondin

A method of making optical quality films is described. A silica film is deposited on a wafer by PECVD (Plasma Enhanced Chemical Vapor Deposition). The deposited film is then subjected to a first heat treatment to reduce optical absorption, wafer warp, and compressive stress. A second film is deposited. This step is then followed by a second heat treatment to reduce optical absorption, wafer warp and tensile stress. The two heat treatments have similar temperature profiles.

Method of reducing stress-induced mechanical problems in optical components

To deposit optical quality films by PECVD (Plasma Enhanced Chemical Vapor Deposition), a six-dimensional space wherein five dimensions thereof correspond to five respective independent variables of which a set of four independent variables relate to the flow-rate of respective gases, a fifth independent variable relates to total pressure, and a six dimension relates to observed FTIR characteristics is first created. Then an optical film is deposited while maintaining three of the set of four independent variables substantially constant as well as the fifth independent variable, and varying a fourth of the set of four independent variables to obtain desired characteristics in the sixth dimension.

Method of depositing optical films

A method for making an integrated photonic device involves depositing buffer, core and cladding layers on the front side of a wafer. A thick tensile stress layer is deposited on the back side of the wafer just prior to performing a high temperature thermal treatment above 600&deg; C. on the cladding layer to prevent the cracking of the layers as a result of the thermal treatment.

Method of preventing cracking in optical quality silica layers

A method is disclosed for depositing an optical quality silica film on a wafer by PECVD. The flows rates for a raw material gas, an oxidation gas, a carrier gas, and a dopant gas are first set at predetermined levels. The total deposition pressure is set at a predetermined level. The deposited film is then subjected to a post deposition heat treatment at a temperature selected to optimize the mechanical properties without affecting the optical properties. Finally, the observed FTIR characteristics of the deposited film are monitored to produce a film having the desired optical and mechanical properties. This technique permits the production of high quality optical films with reduced stress.

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Granby, Canada

Jonathan Lachance