Omega shape channel LDMOS: A novel structure for high voltage applications

• A novel Omega shape channel LDMOS transistor is proposed in this paper.
• Uniform electric field causes high breakdown voltage in the OCH-LDMOS.
• High doping density of right side omega shape channel reduces specific on resistance in the proposed structure.
• The ATLAS simulation shows the high performance of the proposed OCH-LDMOS transistor.

A new device structure for high breakdown voltage and low specific on resistance of the LDMOS device is proposed in this paper. The main idea in the proposed structure is using omega shape channel. The benefits of omega shape channel could be determined by extending depletion region in the drift region that causes low specific on resistance. Also, uniform horizontal electric field would be achieved that results in high breakdown voltage. The proposed structure is called Omega-shape Channel LDMOS (OCH-LDMOS). The simulation with two dimensional ATLAS simulator shows that the breakdown voltage increases to 712 V from 243 V of the conventional LDMOS at 12 µm drift length. Also, effective values of doping, length, and depth of Ω-shape channel are investigated.

A schematic cross-sectional view of the proposed Omega-shape Channel LDMOS (OCH-LDMOS) structure implemented in ATLAS simulator is shown in following figure. The extended channel in the drift side and source side causes high breakdown voltage and low specific on resistance.Figure optionsDownload as PowerPoint slide