Method for forming picture element structure

The invention discloses a method for forming a picture element structure, comprising the following steps of: forming a scanning line and data line segments by utilizing a first conducting layer, forming a channel structure, a first isolation structure and a second isolation structure by utilizing a semiconductor layer and a gate insulation layer, and forming a source electrode, a drain electrode and a common electrode by utilizing a second conducting layer. The first isolation structure and the second isolation structure can prevent the common electrode from electrically connecting to the scanning line and the data line segments and simultaneously expose partial data line segments so that the source electrode can directly contact the data line segment to form a data line. Thereby, the method can make the picture element structure with a screen positioned above the data line without utilizing a semitransparent mask or semi-color light-regulating mask and keep the low impedance of the data line.