Monolithic integration of a thin film transistor over a complimentary transistor

An apparatus comprising:

• a first device that is a III-N field effect transistor;
• and
• a second device above the first device,
• wherein the second device comprises (i) a source terminal and a drain terminal, (ii) a body comprising a semiconductor material including a metal and oxygen, the body extending laterally from the source terminal of the second device to the drain terminal of the second device, and (ii) a gate stack coupled to the body,
• wherein a source terminal of the first device is coupled to the drain terminal of the second device, or a drain terminal of the first device is coupled to the source terminal of the second device, and
• wherein the first device is one of an enhancement mode transistor or a depletion mode transistor, and the second device is the other of the enhancement mode transistor or the depletion mode transistor.

An integrated circuit comprising:

• a first device comprising an enhancement mode III-N heterostructure field effect transistor (HFET) that includes gallium and nitrogen;
• a second device over the first device, the second device comprising a depletion mode thin film transistor (TFT) that includes (i) a body comprising oxide semiconductor, (ii) a source or drain terminal above the body, and (iii) a gate stack below the body;
• and
• a connector to couple a first terminal of the first device to a first terminal of the second device.