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. When making a super junction power device, impurity of a second conductive type may be implanted into an epitaxial layer of a first conductive type to form a floating island of the second conductive type and a pillar of the second conductive type successively through a super junction mask (or reticle) after forming the epitaxial layer of the first conductive type, directly through a well mask (or reticle) before or after forming a well region of the second conductive type, and directly through a contact mask (or reticle) before or after forming a contact structure. Multiple epitaxial processes and deep trench etching process may not be needed. Therefore, the process is simple, the cost is low and yield and reliability are high. Because the super junction power device of the present invention has both the floating island of the second conductive type and the pillar of the second conductive type, in open state, a breakdown voltage may be raised and both Miller capacitance and input capacitance can be decreased and in on state, an on-state resistance can be decreased.