High Electron Mobility Transistors and Integrated Circuits with Improved Feature Uniformity and Reduced defects for Microwave and Millimetre Wave Applications

摘要

High mobility transistors and microwave integrated circuits with an improved uniformity of the width of the smallest of features, an increased lithographic yield and reduced defects in the active components are provided. Before and during fabrication, a first grooving process is performed to partially or completely remove composite epitaxial layers in the field lanes to reduce the initial bow to be smaller than DOF range and to improve the uniformity of the critical dimension. A second grooving process may also be performed to remove composite epitaxial layers in the dicing lanes to further improve the uniformity of the width of the smallest features for the devices and circuits to be made.

主权项

1. A microchip with improved feature uniformity and circuit performance for power switching and millimetre wave applications comprises a plurality of high electron mobility transistors each in a composite epitaxial layers HEMT region on a substrate, a plurality of resistors, capacitors, inductors, transmission lines on said substrate, said microchip having a plurality of x-axis field lanes and a plurality of y-axis field lanes defining a plurality of fields, said composite epitaxial layers comprise a buffer layer having a buffer layer thickness, a conductive channel layer, a Schottky barrier layer, a ledge layer and a doped ohmic contact layer, wherein materials of said composite epitaxial layers in said x-axis field lanes and y-axis field lanes are substantially removed to reduce deformation in said substrate to improve feature uniformity and to reduce unwanted microcracks induced in said composite epitaxial layers in channel regions of said high electron mobility transistors to increase fabrication yield and reliability of said microchips.