self-heating modeling

**Self-heating modeling** is the **electrothermal modeling of temperature rise generated internally by device operation and limited heat extraction** - it predicts local channel and interconnect temperature that often exceeds package sensor readings, directly impacting performance and aging. **What Is Self-heating modeling?** - **Definition**: Model of localized temperature increase caused by on-device power dissipation and thermal resistance. - **Technology Context**: FinFET and gate-all-around structures are especially sensitive due to thermal confinement. - **Inputs**: Power density, activity profile, material thermal conductivity, and layout-level heat spreading paths. - **Outputs**: Transient and steady-state hotspot temperature for reliability and timing analysis. **Why Self-heating modeling Matters** - **Aging Acceleration**: Higher local temperature exponentially increases BTI, EM, and TDDB degradation rates. - **Performance Drift**: Temperature rise changes mobility and resistance, reducing effective speed. - **Model Gap Reduction**: Package sensors alone often miss microscale hotspots that drive failures. - **Design Optimization**: Power delivery and floorplan decisions depend on realistic local temperature prediction. - **Thermal Safety**: Self-heating models support safe operating limits for sustained workloads. **How It Is Used in Practice** - **Power Mapping**: Project workload-dependent dynamic and static power to fine spatial grid. - **Electrothermal Solve**: Iterate temperature-dependent electrical parameters until convergence. - **Control Integration**: Feed hotspot estimates into DVFS and thermal throttling policies. Self-heating modeling is **a foundational requirement for trustworthy advanced-node reliability analysis** - accurate hotspot prediction prevents hidden thermal stress from undermining product lifetime.