ASIC Design Flow

Design Consultation
System Specification
Logic Design
The following link shows the basics of a CMOS logic design. Designs are done by drawing schematics or by writing VHDL code.
Test Pattern(data) Generation
Special Cell Design
Existing blocks or cells can seldom be reused without modification. Examples of such cells are: sigma-delta converters, phase lock loops, analog to digital converters, and digital to analog converters, bandgap references and low power oscillators.
Simulation
Place and Route
Post Layout Simulations
Layout Verification (LVS DRC)
Mask Generation (reticle tooling) -Subcontracted
Wafer Fabrication -Subcontracted
More information can be found on how semiconductors work at How Stuff Works
Test Program Generation -Subcontracted
Prototype Assembly and Test -Subcontracted
Product Delivery
Prototype Evaluation
Production -Subcontracted