Characteristic Studies Of Rectifiers With Schottky Structure

Power semiconductor devices are recognized as a key component of all power electronic systems. With the wide spread use of electronics in the consumer, industrial, medical, and transportation sectors, power devices have a major impact on the economy, because they determine the cost and efficiency of systems. In actual power electronic applications, the devices are demanded for high voltage, low reverse leakage current, low forward voltage drop, fast-switching rectifier features and excellent reverse recovery behavior. For these years, several attempts have been made for the rectifiers with schottky structure.In this paper, the chapters are devoted to various advanced power rectifier structures. The unipolar device structures are first covered in the chapter 2 on the TMBS (Trench MOS Barrier Schottky) and GD-TMBS (Trench MOS Barrier Schottky with Graded Doping Profile) rectifiers. The rectifiers change the profiles of electronic field by MOS structure. The rectifiers exhibit advantaged character. The chapter 3 provides analysis of the MPS (Merged PIN Schottky),SJ-MPS (Super Junction Merged PIN Schottky),SEMI-SJ MPS (SEMI Super Junction Merged PIN Schottky) and TSOX-MPS (A Planarized Silicon Trench Sidewall OXide Merged P-i-n Schottky) rectifiers. The rectifiers exhibit the better reverse I-V character than the conventional schottky rectifier and the much shorter reverse recovery time than the PiN rectifier.In the chapter 4, the rectifiers based on trench sidewall schottky is proposed and demonstrated including TSBS(Trench Schottky Barrier Controlled Schottky),TSS-MPS(Trench Sidewall Schottky Merged PIN Schottky) and TD-MPS(A merged double PiN Schottky rectifier based on trench structure) rectifiers. Some characters of TSBS tectifier have been simulated by SIVAVLCO software. The simulation result exhibits high peak electronic field in the corner of trench structure. Some characters of TSS-MPS tectifier have been simulated by SIVAVLCO software. The simulation result exhibits big reverse leakage current with the long depth of trench. The TD-MPS based on the peak electronic field of TSBS and big reverse leakage current with the long depth of TSS-MPS trench is proposed. By SIVAVLCO and ISE-TACD software, the Experiment shows that the TD-MPS rectifier exhibits the lower forward voltage than the conventional MPS rectifier for high current density and the much shorter reverse recovery time than the PiN rectifier. Physical explanations about the forward and rever recovery Performance are given by the hole concentration and electronic field simulation.