Semiconductor device and method for forming the same

A semiconductor device, comprising:

• a first transistor over a substrate, comprising:
• a first semiconductor channel layer;
• a first gate structure over the first semiconductor channel layer;
• and
• a first source/drain epitaxy structure alongside the first semiconductor channel layer;
• a second transistor vertically above the first transistor, comprising:
• a second semiconductor channel layer
• a second gate structure over the second semiconductor channel layer;
• and
• a second source/drain epitaxy structure alongside the second semiconductor channel layer;
• an isolation structure electrically isolating the first gate structure from the second gate structure;
• and
• a bottom gate contact electrically coupled to the first gate structure, wherein in a first cross-sectional view, the isolation structure has a first portion laterally between the bottom gate contact and the second gate structure.

A semiconductor device, comprising:

• a first transistor over a substrate, comprising:
• a first semiconductor channel layer;
• a first gate structure over the first semiconductor channel layer;
• and
• a first source/drain epitaxy structure alongside the first semiconductor channel layer;
• a second transistor vertically above the first transistor, comprising:
• a second semiconductor channel layer
• a second gate structure over the second semiconductor channel layer;
• and
• a second source/drain epitaxy structure alongside the second semiconductor channel layer;
• an isolation structure electrically isolating the first gate structure from the second gate structure;
• and
• a bottom gate contact electrically coupled to the first gate structure, wherein in a top view of the isolation structure covers three sides of the bottom gate contact.