Resources Contact Us Home
Heterojunction bipolar transistor and method of producing the same

Image Number 7 for United States Patent #6924201.

A heterojunction bipolar transistor of the present invention is produced from a wafer including a substrate and a collector layer of a first conductivity type, a base layer of a second conductivity type and an emitter layer of the first conductivity type sequentially laminated on the substrate in this order. First, the wafer is etched up to a preselected depth of the collector layer via a first photoresist, which is formed at a preselected position on the emitter layer, serving as a mask. Subsequently, the collector layer etched with at least the sidewalls of the base layer and collector layer, which are exposed by the first etching step, and a second photoresist covering part of the surface of the collector layer contiguous with the sidewalls serving as a mask.

  Recently Added Patents
Joining user profiles across online social networks
Fan guide
Techniques for identifying optimized malicious search engine results
Calibrachoa plant named `Balcabdepy`
Method and apparatus for unlocking screen saver
Method and apparatus for reducing combiner loss in a multi-sector, omni-base station
Mobile phone
  Randomly Featured Patents
Bucket top cutting board
Underwater substation
Well logging method and apparatus for NMR and resistivity measurements
Sliding roof for automobiles
Method of preventing cavitation in a fuel injector having a solenoid actuated control valve
Open cell sheeting
Optical waveguide intensity modulator using electro-optic polymer
Methods for fabricating fuse programmable three dimensional integrated circuits
Solid state joining method for continuous structures
Detachable steerable power unit for occupant-propelled wheelchairs