Patent ID: 6589826
Filing Date: 2003-07-08
Classification: H01L

Abstract:
A method of forming a thin film transistor, comprising:forming a semiconductor active layer on a first insulating layer; sequentially forming a second insulating layer and a first conductive layer over the semiconductor active layer; patterning the second insulating layer and the first conductive layer to form a gate insulating layer underlying a gate electrode, and to form a first and a second sub-gate insulating layers underlying a first and a second sub-gate electrodes, respectively; forming an ion injection mask covering at least a portion of each of said first and second sub-gate electrodes, and covering an entire region extending from said first sub-gate electrode to said second sub-gate electrode; implanting a first dose of impurities into exposed portions of the semiconductor active layer using the ion injection mask to form a heavily doped source region abutting a first sub-channel region under said first sub-gate electrode and a heavily doped drain region abutting a second sub-channel region under said second sub-gate electrode; removing said ion injection mask; implanting a second dose of impurities into the semiconductor active layer using the gate electrode and the first and second sub-gate electrodes as a mask to form a first and a second lightly doped regions, wherein said first lightly doped region is between and abutting said first sub-channel region and a channel region underlying said gate electrode, and said second lightly doped region is between and abutting said channel region and said second sub-channel region, and wherein said first and second lightly doped regions are aligned with said channel region and said first and second sub-channel regions in a straight line; and forming a pixel electrode electrically connected to said drain region, wherein a portion of said pixel electrode forms a first electrode of a storage capacitor, and a conductive line connected to said first and second sub-gate electrodes forms a second electrode of said storage capacitor.