COG & TCP 
   
   Chip-On-Glass – is one of the high-tech mounting methods that 
uses Gold Bump or Flip Chip IC’s, and implemented in most 
compact applications. Chip-On-Glass integrated circuits were 
first introduced by Epson. In flip-chip mounting, the IC chip
is not packaged but is mounted directly onto the PCB as a bare
chip. Because there is no package, the mounted footprint of the
IC can be minimized, along with the required size of the PCB.
This technology reduces a mounting area and is better suited 
to handling high-speed or high-frequency signals. 

  Advantages: 
  Very space economical. Chip-On-Glass LCD modules can be as 
thin as 2 mm. 
  Cost effective over COB, especially in graphic LCD modules,
because much less IC's are required. 
  More reliable than TAB because of the weakness in the bond 
area of TAB.
  Disadvantages:
  COG can only be used at a certain resolution level where the
lines are not too fine. At very fine pitches COG becomes difficult
to test, and TAB is the preferred approach. It may be more 
cost-effective to use TAB or COB, if a designer has to integrate
a keypad or indicator around the display. The active area is not 
centered within the outline but offset, because of the area where 
the circuits are. Since the Chip-On-Glass integrated circuit has
been invented by Epson, COG technology became very popular due 
to the demand for more compact applications. In the near future 
we will see this IC mounting method finding its applications in 
many other equipment than cellular phones, PDA's, computer network
servers, satellite receivers, etc.