Average Co-Inventor Count = 3.10
ph-index = 3
The patent ph-index is calculated by counting the number of publications for which an author has been cited by other authors at least that same number of times.
Company Filing History:
1. Nippon Telegraph and Telephone Corporation (4 from 5,290 patents)
2. Hitachi, Ltd. (2 from 42,517 patents)
4 patents:
1. 4820609 - Highly sensitive positive resist mixture
2. 4808829 - Mark position detection system for use in charged particle beam apparatus
3. 4699870 - Patterning method
4. 4692579 - Electron beam lithography apparatus