h-gate

**H-Gate** is a **transistor layout technique in SOI where the gate forms an "H" shape** — with the horizontal bar serving as the actual gate over the channel and the vertical bars providing body contacts on both sides, eliminating floating body effects while maintaining compact layout. **What Is an H-Gate?** - **Shape**: The gate poly forms an "H". The crossbar is the active channel. The vertical bars extend to diffusion body ties. - **Advantage**: Body contact integrated directly into the gate structure — no extra routing needed. - **Use**: PD-SOI analog circuits where body potential control is critical. **Why It Matters** - **Analog Performance**: Ensures stable output resistance and gain by keeping the body potential fixed. - **Area Efficiency**: More compact than separate T-shaped body contacts. - **PD-SOI Era**: Was a common layout practice for IBM and AMD PD-SOI designs. **H-Gate** is **a clever geometrical trick** — embedding body contacts directly into the gate layout to solve the floating body problem with minimal area overhead.