Patent · US Expired

Method for making defect-free zone by laser-annealing of doped silicon

US4181538A · kind A · utility

86Cited by
5References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 26, 1978
Grant dateJan 1, 1980
Priority date
Expiry dateSep 26, 1998

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S148/097
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

This invention is a method for improving the electrical properties of silicon semiconductor material. The method comprises irradiating a selected surface layer of the semiconductor material with high-power laser pulses characterized by a special combination of wavelength, energy level, and duration. The combination effects melting of the layer without degrading electrical properties, such as minority-carrier diffusion length. The method is applicable to improving the electrical properties of n- and p-type silicon which is to be doped to form an electrical junction therein. Another important application of the method is the virtually complete removal of doping-induced defects from ion-implanted or diffusion-doped silicon substrates.

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