Palo Alto Research Center Inc.

Novalux, Inc.

René A Lujan

William S Wong

Steven E Ready

Alan G Lewis

Aram Mooradian

Gideon W Yoffe

Kateri E Paul

Hailong Zhou

Glen Phillip Carey

Mark A Emanuel

Ian Jenks

Jacy R Titus

A method for performing a liftoff operation involves printing a liftoff pattern using low-resolution patterning techniques to form fine feature patterns. The resulting feature size is defined by the spacing between printed patterns rather than the printed pattern size. By controlling the cross-sectional profile of the printed liftoff pattern, mask structures may be formed from the liftoff operation having beneficial etch-mask aperture profiles. For example, a multi-layer printed liftoff pattern can be used to create converging aperture profiles in a patterned layer. The patterned layer can then be used as an etch mask, where the converging aperture profiles result in desirable diverging etched features.

Patterning using wax printing and lift off

A method of fabricating a semiconductor device is described. In this method, a starting substrate of sufficient thickness is selected that has the required defect density levels, which may result in an undesirable doping level. Then a semiconductor layer having a desired doping level is formed on the starting substrate. The resulting semiconductor layer has the required defect density and doping levels for the final product application. After active components, electrical conductors, and any other needed structures are formed on the semiconductor layer, the starting substrate is removed leaving a desired thickness of the semiconductor layer. In a VECSEL application, the active components can be a gain cavity, where the semiconductor layer has the necessary defect density and doping levels to maximize wall plug efficiency (WPE). In one embodiment, the doping of the semiconductor layer is not uniform. For example, a majority of the layer is doped at a low level and the remainder is doped at a much higher level. This can result in improved WPE at particular thicknesses for the higher doped material.

Method of fabrication of a support structure for a semiconductor device

Growing community of inventors

Sunnyvale, CA, United States of America

René A Lujan