The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 06, 1998
Filed:
Dec. 22, 1994
Steven G Eaton, Sunnyvale, CA (US);
Rusmin Kudinar, Union City, CA (US);
William R Wheeler, Saratoga, CA (US);
Tencor Instruments, Santa Clara, CA (US);
Abstract
A profilometer has a constant force mechanism for biasing of the stylus arm. The mechanism has a centrally-aligned configuration of the moving magnet relative to the magnetic coil and also has a magnetic shield isolating these elements from other ferromagnetic materials in the assembly. The moving magnet is made of a material that is hard magnetically and the magnetic shield is made of a series of low hysteresis, high permeability materials. The force thus generated by the stylus biasing device is very linear with the drive current upon the magnetic coil at any particular position of the stylus, thereby allowing for control and predictability of the stylus force upon the surface to be profiled. This predictability is used for dynamic stylus force adjustments during profiling of a specimen. The profilometer is also equipped with a balanced, spring-loaded stylus-stabilizing sensor assembly, task-specific dual-view optics for protection of the delicate stylus assembly, and a temperature drift compensator.