Trench mosfet with periodic p-island shielding

A semiconductor structure, comprising:

• a plurality of trench structures extending, at least partially, within a stack of doped semiconductor layers, the plurality of trench structures including first trench structures and second trench structures, wherein the second trench structures are located between two adjacent first trench structures;
• a gate structure disposed within the first trench structures and the second trench structures;
• and
• a plurality of shielding structures embedded, at least partially, within the stack of doped semiconductor layers surrounding the gate structure within the first trench structures, the plurality of shielding structures being separated by a distance selected based on initiating a three-dimensional pinch-off effect between adjacent shielding structures,
• wherein the gate structure within the second trench structures is surrounded by the stack of doped semiconductor layers.

A semiconductor structure, comprising:

• a semiconductor substrate of a first conductivity type, the semiconductor substrate including silicon carbide;
• a drift layer of the first conductivity type located above the semiconductor substrate;
• a channel layer of a second conductivity type located above the drift layer, the second conductivity type of the channel layer being opposite to the first conductivity type of the drift layer;
• a source region of the first conductivity type located above the channel layer;
• a plurality of trenches penetrating through the source region, the channel layer and a portion of the drift layer;
• an insulating region lining the plurality of trenches, wherein the insulating region includes a bottom portion, a lower side portion and an upper side portion;
• a gate electrode located within each of the plurality of trenches lined with the insulating region;
• and
• a plurality of shielding structures of the second conductivity type located around the gate electrode, wherein the plurality of shielding structures covers sidewalls and a bottom of the plurality of the trenches, the plurality of shielding structures being arranged in an island-like manner.