wafer coring
                     What Is Wafer Coring? 
Wafer coring is a process used to remove the core of a 
semiconductor wafer and create a flat surface for 
subsequent processes. This process is also called edge 
polishing or beveling and it improves the yield of post-
processing by removing Epic defects. Wafer coring is 
usually done for silicon, ingots, or a combination of these. 
Listed below are some of the services that can be 
performed on wafers. 
Laser cutting 
The process of laser cutting wafers is used to create 
individual dies from a single wafer. This process involves a 
mechanical cutter that does not contact the top surface of 
the wafer, while a laser creates scribes in the wafer's 
surface. The laser then cuts the wafer's surface into 
individual dies. The laser's high speed and low thermal 
conductivity make it ideal for manufacturing complex 
electronic components. 

Mechanical dicing 
The mechanical dicing process of silicon wafers consists of 
spinning abrasive discs with diamond blades that are 
bonded to an electroplated nickel matrix. The spinning 
abrasive discs rotate at high speeds. This process has several 
challenges, including the possibility of clogging, changes in 
the nozzle adjustment, and operator error. In order to 
overcome these challenges, mechanical dicing requires an 
on-line monitoring system for blade torque. 
Die attach film 
A die attach film for wafer coring comprises an adhesive 
layer for attaching a semiconductor chip to a lead frame or 
wiring board. In one embodiment, the die attach film 
comprises a thickness ratio of 0.2 to 0.5. In another 
embodiment, the die attach film is a combination of two or 
more layers, and the thickness ratio is 0.1 to 0.25. The 
adhesive layer may be made from polyethylene 
terephthalate, polytetrafluoroethylene, polypropylene, or 
butadiene. 
Additional wafer flats 
To make semiconductor wafers smaller, they undergo 
processes called wafer coring. These processes include 
downsizing a silicon wafer to a desired diameter and 
thickness, as well as cutting, scribing, and full penetration 
cuts. While wafer coring can be performed on any size 
or shape of the silicon wafer, it is recommended to start 
with a sample. Additional wafer flats are useful for testing 
different coring techniques and evaluating the effectiveness 
of each method. 
Backgrinding 
Backgrinding is a process where the back side of a silicon 
wafer is ground to remove imperfections. The first step in 
this process is tape lamination, which attaches an adhesive 
tape to the front surface of the wafer. The silicon 
compound that forms the back side of the wafer spreads 
out in all directions during back grinding. The force of this 
grinding process can damage a wafer, particularly larger 
ones. To protect these softer wafers from damage, a thin 
blue tape is placed over the wafer to absorb any ultraviolet 
light.