Resources Contact Us Home
Browse by: INVENTOR PATENT HOLDER PATENT NUMBER DATE
 
 
Method of manufacturing semiconductor device including formation of alignment mark










Image Number 7 for United States Patent #5310691.

A p.sup.- semiconductor substrate has a surface which is high in a memory cell region and low in a peripheral circuit region. An n.sup.+ buried semiconductor layer of uniform thickness is formed on the substrate. An n.sup.- epitaxial layer formed on the buried semiconductor layer is thin in the memory cell region and thick in the peripheral circuit region, so that the surface of the epitaxial layer can be flat. A concave or convex step is formed on the surface of the epitaxial layer in a boundary portion between the memory cell region and the peripheral circuit region in order to use it as an alignment mark in a later processing step.








 
 
  Recently Added Patents
System and method for associating data relating to features of a data entity
Tuberculosis vaccines comprising antigens expressed during the latent infection phase
Photodetectors using resonance and method of making
Electrostatic image forming apparatus utilizing index patterns for toner image alignment
System, medium, and method compensating brightness of an image
Printing plate and method for manufacturing solar cell element using the printing plate
Nail dryer
  Randomly Featured Patents
Draining system for outboard engine
Flexible hub magnetic gyro wheel
Heat assisted magnetic recording film including superparamagnetic nanoparticles dispersed in an antiferromagnetic or ferrimagnetic matrix
Security pouch to be clipped to articles of clothing
Folding, head mounted display unit
Engine starting system and method
Method of making combination toothbrush and storage/dispenser apparatus
Method for making fiber-reinforced ceramic matrix composite
Method and device for inductive transmission of electric power to a plurality of mobile consumers
Automated diagnostic service