Liquid crystal display device and manufacturing method of the same

A liquid crystal display device comprising:

• an active matrix substrate;
• a counter substrate disposed to face the active matrix substrate;
• a liquid crystal layer provided between the active matrix substrate and tie counter substrate;
• and
• a plurality of pixels arranged in a matrix including a plurality of rows and a plurality of columns,
• wherein the active matrix substrate includes
• a first substrate having a main surface,
• a plurality of light blocking layers provided on the main surface of the first substrate,
• a lower insulating layer provided to cover the plurality of light docking layers,
• pixel TFTs, each pixel TFT being provided corresponding to each of the plurality of pixels, the pixel TFT including an oxide semiconductor layer provided on the lower insulating layer, a gate insulating layer provided on the oxide semiconductor layer, and a gate electrode provided to face the oxide semiconductor layer with the gate insulating layer interposed between the gate electrode and the oxide semiconductor layer,
• a plurality of gate wiring lines extending in a row direction, each gate wiring line being formed from a conductive film the same as the gate electrode,
• a plurality of source wiring lines extending in a column direction,
• a plurality of pixel electrodes, each pixel electrode being provided in each of the plurality of pixels and electrically connected to the pixel TFT,
• an interlayer insulating layer provided to cover the oxide semiconductor layer, the gate electrode, and the plurality of gate wiring lines, and
• a common electrode provided on the interlayer insulating layer,
• the oxide semiconductor layer includes a channel region, a first low-resistive region, and a second low-resistive region, the first low-resistive region and the second low-resistive region being located on both sides of the channel region and having specific resistances Lower than the channel region,
• the plurality of source wiring lines are located between the main surface of the first substrate and the lower insulating layer, and are formed from a conductive film the same as the plurality of light blocking layers,
• the pixel electrode is formed from an oxide film the same as the oxide semiconductor film, and is continuous with the second low-resistive region of the oxide semiconductor layer, and
• the active matrix substrate further includes a connection electrode formed from a transparent conductive film the same as the common electrode, the connection electrode connecting any one of the plurality of source wiring lines to the first low-resistive region of the oxide semiconductor layer.