In this thesis a novel N-channel UHV 700v-800v JFET innovated device structure combined with control gate is studied. The UHV 600v LDMOS popular for high voltage power switching device and it may be ON/OFF device. For OFF device there are many LDMOS devices available but when it comes for ON device JFET is required where as LDMOS is OFF device.
Since JFET is a normally on device so it is widely used as sensor and safety devices like fire alarm and automobile sensor etc. The various Pinch-off voltage can be adjusted through Nwell mask and gap between P-top and PPlus by keeping the breakdown voltage in between the range of 700v-800v. By using 2D simulation method instead of 3D simulation is more time convenient and time saving for optimization and design. Multi ring P-top structure is not only capable of adjusting various Pinch-off voltage it also enhances breakdown compared with uniform P-top structure.
We can design the desired pinch-off voltage without any additional process mask. N-channel JFETs with different pinch-off voltages can be implemented in the low-cost BCD Integration.