Patent · US Expired

Semiconductor thin film decomposing method, decomposed semiconductor thin film, decomposed semiconductor thin film evaluation method, thin film transistor made of decomposed semiconductor thin film, and image display device having circuit constituted of thin film transistors

US7151046B2 · kind B2 · utility

6Cited by
4References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 28, 2004
Grant dateDec 19, 2006
Priority date
Expiry dateAug 22, 2024

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D86/0229
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A surface roughness of a polycrystalline semiconductor film to be formed by a laser annealing method is reduced. A transmittance distribution filter is disposed at the optical system of a laser annealing apparatus. The transmittance distribution filter controls an irradiation light intensity distribution along a scanning direction of a substrate formed with an amorphous silicon semiconductor thin film to have a distribution having an energy part equal to or higher than a fine crystal threshold on a high energy light intensity side and an energy part for melting and combining only a surface layer. This transmittance distribution filter is applied to an excimer laser annealing method, a phase shift stripe method or an SLS method respectively using a general line beam to thereby reduce the height of protrusions on a polycrystalline surface.

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