Resources Contact Us Home
Browse by: INVENTOR PATENT HOLDER PATENT NUMBER DATE
 
 
Method for manufacturing semiconductor rectifier










Image Number 2 for United States Patent #4977107.

Rectifiers of excellent characteristics may be more economically fabricated by a process in which a cavity is first etched in a non-epitaxial semiconductor wafer to a depth in the range of typically 15-25 percent of the initial wafer thickness. Simultaneous diffusion of N and P type dopants is used to provide (for an N type substrate) a P+ region in the bottom of the cavity and surrounding surface, and an N+ region on the opposite face of the wafer. A mask is then provided in the cavity bottom and the surrounding wafer regions etched to remove the P+ dopant outside the cavity thereby re-exposing the surrounding region of the original N type substrate. The P+ region may be level with or protrude slightly from the substrate surface. The junction formed between the P+ region in the cavity bottom and the N type substrate has a gradual contour where it intersects the surface thereby providing a more favorable field distribution. Passivation and metallization are provided in the conventional manner. The resulting devices may be fabricated in very thin wafers without significant mechanical breakage loss.








 
 
  Recently Added Patents
Storage system, control method therefor, and program
Printed wiring board with reinforced insulation layer and manufacturing method thereof
Method and system for phase-sensitive magnetic resonance imaging
Vehicles with electric motor
Sensor coating
Device for maneuvering a vehicle using maneuvering moves using at least one trajectory
Solid-state imaging apparatus and imaging system
  Randomly Featured Patents
Botryoccocus braunii triterpene synthase proteins and nucleic acid molecules, and methods for their use
Recessed channel array transistor (RCAT) structures
Method, medium, and system estimating pose of mobile robots
Method and system for remotely sensing the file formats processed by an e-mail client
Remanufacturing method for process cartridge
Transparent panel having high reflectivity for solar radiation and a method for preparing same
Secure scan design
Modular-type home gateway system including ADSL controller and homePNA controller
Radiation image erase unit for use with stimulable phosphor sheet
Production of non-woven fabrics