Ann F. Koo
11Patents
0Active
11Granted
29Portfolio score
Filing activity: May 26, 1989 → Feb 24, 2000
Most-cited patents
| Patent | Title | Area | Cited by | Status |
|---|---|---|---|---|
| US5452078A | Method and apparatus for finding wafer index marks and centers | Electricity | 43 | Expired |
| US5270560A | Method and apparatus for measuring workpiece surface topography | Physics | 22 | Expired |
| US5708279A | Method and apparatus for measuring surface topography | Physics | 17 | Expired |
| US5118955A | Film stress measurement system having first and second stage means | Physics | 14 | Expired |
| USD450000S | Multiple environment testing chamber | General | 11 | Expired |
| US5696383A | Method and apparatus for measuring the curvature of wafers with beams of different wavelengths | Electricity | 9 | Expired |
| US6546820B1 | Method and apparatus for multifunction vacuum/nonvacuum annealing system | Physics | 9 | Expired |
| US5369286A | Method and apparatus for measuring stress in a film applied to surface of a workpiece | Physics | 8 | Expired |
| US5523582A | Method and apparatus for measuring the curvature of wafers with a laser source selecting device | Electricity | 8 | Expired |
| US5917191A | Apparatus for measuring surface topography | Physics | 4 | Expired |
| US5532499A | Beam spot position detector having a detector moving mechanism | Physics | 2 | Expired |
Source: USPTO / EPO open patent data. Counts and citation impact are objective bibliographic measures.