|
Total Thickness Variation：
The difference between the highest and the lowest elevation of the top surface of a clamped wafer.
The back surface referenced. |
|
|
Total Indicated Reading：
The difference between the highest point above and the lowest point below the front surface referenced focal plane of a clamped wafer.
3 points on the front surface generally used. |
|
|
Local Thickness Variation:
The difference between the highest point and the lowest point within a site of the top surface of a clamped wafer.
The back surface referenced. |
|
|
Percent LTV：
Percentage of sites on a wafer within the specified LTV value. |
|
The difference between the highest point above and the lowest point below the front surface referenced focal plane of an
unclamped wafer.
A least square fit on the front surface generally used. |
|
: 1409KB ]
