The Study Of Field Plate Of AlGaN/GaN Schottky Barrier Diode

In the last few decades,with the development of the semiconductor industry,the third generation wide band gap semiconductor is gradually becoming the most notable twenty-first Century materials,including a nitride semiconductor device which focus more researchers on researching,especially the two-dimensional electron gas between the GaN and AlGaN which contains a very high electron concentration,while the nitride semiconductor can work at high temperature,high frequency,and strong radiation environment.The advantages of this natural advantages let the nitride devices become a new hope working in harsh environment,excellent material properties for the future military and civilian which has the potential of a semiconductor material.AlGaN/GaN Schottky barrier diode and AlGaN/GaN high electron mobility transistor HEMT have been developed together.Through years of efforts,AlGaN/GaN Schottky barrier diode is gradually becoming mature for people around the world.The breakdown voltage of Schottky diode is focusing many researchers on attention,most effectively enhance the pressure without affecting the forward characteristics is by way of the field plate structure on Schottky anode,so this paper focuses on analysising the traditional field plate,and then we simulate several variant of the proposed new field plate by simulation software Silvsco,and put forward the possible process methode and process for workers,the main aspects of the research are as follows:1.We explain the mechanism of improving the breakdown voltage of lateral field plate,and find out the relationship between the lateral field plate length,the thickness of the passivation layer and the breakdown voltage,and then further explaining the rules.We study a new field plate structure of Stepped Insulator Floating Field Plate(SFFP),and analysis of the electric field distribution in internal channel and carriers distribution at the same voltage.We explain the reason why the Stepped Insulator Floating Field Plate is better than the other types of field plate structure.Finnaly,we put the Stepped Insulator Floating Field Plate device into the simulation alone,and come put of the best numerical results of Stepped Insulator Floating Field Plate' passivation layer thickness and the horizontal position.2.According to the device LDMOS's vertical field plate structure,we simulate a vertical field plate for AlGaN/GaN SBD,the simulated effect of two parameters on the breakdown voltage the length of vertical field plate and thickness of the passivation layer.We observe the two parameters on the breakdown voltage and the internal electrical field,and then draw the 3D electric field distributiuon of the GaN buffer layer effect.Finally the summary about the advantages of vertical field is coming out.3.We call the combination of lateral field plate and vertical field plate ALVFP-SBD.Fixed length of vertical field plate and the thickness of passivation layer is in the new device,and we analysis the reverse characteristics of these two types of structure.We used the 3D electric field distribution in GaN buffer layer to conclude the influence to the to also these two types of field plate structure.We simulate the forward and reverse characteristics,and calculate the FoM values.We give the possible process of deep electrode device.We simulate the temperature characteristics of AlGaN/GaN Schottky barrier diode.