the present invention discloses a method of manufacturing an active matrix display device , comprising : a ) forming a semiconductor layer on an insulating substrate ; b ) forming a gate insulating layer over the whole surface of the substrate while convering the semiconductor layer ; c ) forming a gate electrode on the gate insulating layer over the semiconductor layer ; d ) forming spacers on both side wall portions of the gate electrode while exposing both end portions of the semiconductor layer ; e ) ion - implaing a high - density impurity into the semiconductor layer to form high - density source and drain regions in the semiconductor layer ; f ) depositing sequentially a transparent conductive layer and a metal layer on the inter insulating layer ; g ) patterning the transparent conductive layer and the metal layer to form the source and drain electrodes , the source and drain electrodes directly contacting the high - density source and drain regions and having a dual - layered structure ; h ) forming a passivation layer over the whole surface of the substrate ; i ) etching the passivation layer and the metal layer to form an opening portion exposing a portions of the transparent conductive layer , thereby forming a pixel electrode ; and j ) performing a reflow process to cover the metal layer in the opening portion by the passivation layer .