Research On Low EMI IGBT With New Charge Layer In The Body

As the core component of power electronic system,Insulated Gate Bipolar Transistor（IGBT）is widely used in industrial control,automotive electronics,aerospace and other fields.However,with its application in higher switching frequency and more complex environment,a good tradeoff between switching on power consumption and Electromagnetic Interference（EMI）noise is required to improve the reliability of devices,which has become the focus of research.In order to solve this problem,two Hole Path Insulated Gate Bipolar Transistor（HP-IGBT）with low EMI noise are proposed by introducing a new charge layer into the body without affecting the static and interruption characteristics of the device,as follows:1.The first proposed structure is the Low Resistance Hole Path Insulated Gate Bipolar Transistor（LR-HP-IGBT）,which introduces a P⁺layer at the floating P-base adjacent to the virtual gate,forming a high-low junction with the original floating p-base.During turn-on period,LR-HP-IGBT further enhances the export of holes in the floating P-base,resulting in a rate of rise of the floating P-base is from 4.59V decreased to 2.51V/μs,so LR-HP-IGBT has less EMI noise.The simulation shows that the maximum d I_C/dt and d V_KA/dt of the new structure are reduced by 37.1%and 12.1%respectively,compared with the HP-IGBT structure at the same turn-on energy loss.At the same on-state voltage drop,both HP-IGBT and LR-HP-IGBT structures have the same turn-off energy loss.Finally,the transverse width,doping concentration and junction depth of P⁺layer are optimized by simulation 0.3μm,5×10¹⁹cm^-3,1μm.2.The second proposed structure is N_D⁺-HP-IGBT,which introduces an N_D⁺layer below the floating p-base and immediately adjacent to the gate oxygen,forming a high-low junction with the original N-drift region.During turn-on period,the newly introduced N_D⁺layer blocks the accumulation of holes near the gate oxygen.Compared with the HP-IGBT structure,the hole concentration near the gate oxygen of the new structure is reduced by 52.3%,so the N_D⁺-HP-IGBT has lower collector current overshoot and d I_C/dt.The simulation shows that under the same turn-on energy loss,the maximum value of d I_C/dt and the maximum value of d V_KA/dt are reduced by 31.6%and 9.21%respectively,Moreover,the two structures have a similar trade-off relationship between on-state voltage drop and turn-off energy loss.Finally,the transverse width,doping concentration and junction depth of N_D⁺layer are optimized by simulation 0.3μm,6×10¹⁵cm^-3,0.4μm.