Semiconductor device including two thin-film transistors and method of fabricating the same

A semiconductor device, comprising:

• a base substrate;
• and
• a first thin-film transistor and a second thin-film transistor disposed on the base substrate,
• wherein the first thin-film transistor comprises a first output electrode, a first semiconductor pattern including a crystalline semiconductor material, and a control electrode disposed on the first semiconductor pattern,
• wherein the second thin-film transistor comprises an input electrode, a second output electrode, the control electrode, a second semiconductor pattern, which is disposed on the control electrode and including an oxide semiconductor material, and a conductive pattern, which is disposed on the second semiconductor pattern and exposes a portion of the second semiconductor pattern,
• wherein the control electrode is disposed between the first semiconductor pattern and the second semiconductor pattern,
• wherein the first semiconductor pattern, the control electrode, and the second semiconductor pattern are overlapped with each other, when viewed on a plane, and
• wherein the conductive pattern passes through the second semiconductor pattern and contacts the first semiconductor pattern.