Thermal Behavior of Self-heating Effect in FinFET Devices Acting on Back-end Interconnects

Thermal impact on back-end interconnects resulted from self-heating (SH) effect in FinFET devices is investigated here. The self-heating effect in FinFET devices will generate more heat in fin structures than planar devices and influence the reliability of interconnects. In this study, testing structures including metal sensors of different metal layers are designed, fabricated and measured, as well as a computer-aided finite element model is also built and utilized in this report. With FinFET devices, the evaluation includes temperature saturation with the number of powered devices, temperature rising in different metal layer, and self-heating effect accompanying with joule heating (so-called coupling effect). This investigation shows the contribution of SH effect would change with varying joule heating. It is important to considering the temperature rising from SH effect when assess the risk of back-end interconnects reliability.