Electro-thermal Modeling Of Advanced Active Devices

In the past three decades,the development of semiconductor technology has followed Moore's law,which means that the feature size of the device is shortened by half every two years.The shrinking size has caused severe self-heating effects for active devices,which will affect device performance and reliability.Meanwhile,the accurate modeling of the electrical characteristics of active devices must also consider the effects of self-heating.Therefore,research on the self-heating effect and electrothermal coupling characteristics of advanced active devices is of great significance.Based on TCAD simulation,this paper studies the electrothermal characteristics of GaN HEMT and FinFET devices,and proposes an equivalent thermal resistance extraction method to characterize the drain current degradation caused by device self-heating effect.Then,based on the equivalent thermal resistance,an electro-thermal coupling model of GaN HEMT and FinFET was constructed.In addition,a FinFET analytical thermal model considering self-heating effect is constructed,which has the characteristics of accurate prediction and fast simulation speed.The main work includes the following three items:(1)Modeling and verification of electro-thermal coupling characteristics of GaN HEMT device.First,a compact electrical model of the GaN HEMT device was constructed,and then based on the equivalent thermal resistance extracted by TCAD electro-thermal simulation,an electro-thermal coupling model of the device was constructed and compared with TCAD electro-thermal simulation.(2)Modeling and verification of electro-thermal coupling characteristics of FinFET device.First,a compact electrical model of a FinFET device is constructed.Then,a FinFET electro-thermal coupling model was constructed using a method similar to GaN HEMT,and compared with TCAD electro-thermal simulation.(3)Based on TCAD electro-thermal simulation,FinFET heat source distribution under different doping and bias voltages was studied.Then,an analytical thermal model of FinFET was constructed based on the steadystate heat conduction equation,and compared with COMSOL thermal simulation.The results show that the model can accurately characterize the thermal characteristics of the device channel under different device doping and bias voltage conditions.