Patent · US Expired

Method for making liquid crystal display device with reduced mask steps

US5998230A · kind A · utility

51Cited by
3References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 22, 1998
Grant dateDec 7, 1999
Priority date
Expiry dateOct 22, 2018

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02F1/136227
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

In a method for making a liquid crystal display device, a first conductive film is formed on a substrate, and patterned to form a gate electrode and a gate line; a gate insulating film for covering the gate electrode and the gate line, a semiconductor film, an impurity-doped semiconductor film, and a second conductive film are continuously formed; the second conductive film and the impurity-doped semiconductor film are patterned using a common mask to form a source electrode, a source line, and a drain electrode from the second conductive film and to form an ohmic contact layer from the impurity-doped semiconductor layer; an insulating film is formed onto at least the source electrode, the source line, the drain electrode, and the semiconductor film; the insulating film, the semiconductor film, and the gate insulating film are patterned using a common mask to form a thin film transistor to be in contact with a pixel electrode; a transparent conductive film is deposited on the non-deposited section of the substrate and patterned to form the pixel electrode; and a liquid crystal is enclosed between the resulting thin film transistor substrate and a counter substrate.

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