Super junction power device and method of making the same

Abstract

The present invention provides a power device with super junction structure (or referred to as super junction power device) and a method of making the same. A floating island of a second conductivity type of a cell region, a floating island of the second conductivity type of a termination region, a pillar of the second conductivity type of the cell region and a pillar of the second conductivity type of the termination region may be formed through adding a super junction mask (or reticle) after forming the epitaxial layer of a first conductivity type, through a well mask (or reticle) before or after forming a well of the second conductivity type, and through a contact mask (or reticle) before or after forming a contact structure. Therefore, the process is simple, the cost is low and yield and reliability are high. A breakdown voltage (or referred to as withstand or blocking voltage) may be raised as a result of the charge sharing effect of the floating island of the second conductivity type and the pillar of the second conductivity type in the cell region and both Miller capacitance and input capacitance can be decreased. An on-state resistance can be decreased due to a higher doping level of the epitaxial layer of a first conductivity type allowed to use without degrading the breakdown voltage. A withstand (or blocking) voltage in the termination region may be raised, an area thereof may be reduced, and a whole area of a high voltage device may be decreased because of the floating island of the second conductivity type and the pillar of the second conductivity type of the termination region.