Method for the adjustment of a semiconductor disc relative to a radiation mask in X-ray photolithography
Abstract
Abstract In an illustrative embodiment marks with dual x-ray permeable apertures are at three spaced locations on the mask and transmit x-ray beams which are directed obliquely to the semiconductor surface. In this case, the marks on the semiconductor disc may be formed by monocrystals shaped in conformity with the incident beam cross section and located so as to produce reflected x-ray beams which intersect correspondingly shaped further apertures of the respective dual aperture marks on the mask. Alternatively the beams may impinge on the surface of the semiconductor disc itself at an angle to produce reflection, with x-ray absorbing material surrounding each reflecting region. In either case the reflected beams as transmitted by the further apertures are detected as a measure of the degree of parallelism of the mask and semiconductor disc.
Inventors
- 👤 Eckart Hundt
Bibliographic Details
Claims Analysis
Total Claims: 7References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-02-04 | 1983-08-06 | 1984-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-02-04 | 1987-08-06 | 1988-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-02-04 | 1991-08-06 | 1992-02-05 | $7700.00 | Window Closed / Lapsed |