Integrated circuit devices including discharging path and methods of forming the same

A method of forming an integrated circuit device, the method comprising:

• forming a stacked structure on a substrate, the stacked structure comprising lower channel layers, upper channel layers, and an isolation layer between the lower and upper channel layers;
• forming source/drain regions in the stacked structure, the source/drain regions comprising lower source/drain regions having a first conductivity type, and upper source/drain regions having a second conductivity type that is opposite from the first conductivity type;
• forming gate structures in the stacked structure, the gate structures comprising lower gate structures and upper gate structures;
• and
• forming a discharging path between an upper gate structure and the substrate, wherein the discharging path extends through the isolation layer and comprises a diode structure,
• wherein at least a portion of the diode structure is below an upper surface of the substrate.