Structure and Method of Forming Trench MOSFET Having A Box Shaped Channel and Improved On Resistance Using Double Charged Channel Implant
Publication Date: 2004-Mar-16
The IP.com Prior Art Database
Keywords Trench, MOSFET, Box Channel, On Resistance (RDSon), Double Charged, Implant, Voltage Threshold (Vt), P-Channel Background Trench MOSFET device electrical performance is highly dependent upon precisely forming channel regions having optimized doping concentrations and shape. Channel shapes such as "box-shaped" are well known in the art to improve Trench device electrical performance such as RDSon (1, 2). P-channel devices for example rely heavily on costly implantation and anneal manufacturing equipment and use complex and time consuming process to form such shaped channel regions. Unfortunately, existing process exhibit poor repeatability and process control leading to devices having poorly shaped channel with lackluster electrical performance. Thus, for at least the above reasons it is desirable to devise a novel structure and method of forming Trench MOSFET having a box shaped channel and improved on resistance.