Patent · US Expired

Method and apparatus for laser irradiating semiconductor material

US4316074A · kind A · utility

52Cited by
17References
28Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 20, 1978
Grant dateFeb 16, 1982
Priority date
Expiry dateDec 20, 1998

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB23K26/0823
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

A laser system is disclosed for facilitating transient surface heating and/or melting and regrowth of amorphous, polycrystalline or imperfect crystalline semiconductor wafer material. This system also has specific application to gettering of impurities and the annealing-out of defects within a semiconductor wafer. In the system, a number of circular target-wafers are arranged around the periphery of a turntable. The turntable rotates while a simple, slow-moving beam-delivery system moves radially with respect to the turntable delivering a helical scan which may also be in the form of a multiple-track. Use of the turntable with a multiple wafer load allows efficient batch-processing. Blocking masks may be employed when it is desired to irradiate only selected areas of the semiconductor substrates.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.