Semiconductor device having a plurality of elements on one semiconductor substrate and method of manufacturing the same

A semiconductor device comprising:

• a semiconductor substrate having a first surface and a second surface and including a plurality of sections having different thicknesses between the first surface and the second surface, the plurality of sections including a first section having a first thickness and a second section having a second thickness, the second section being a thinnest section in the plurality of sections, the first thickness being greater than the second thickness, and the semiconductor substrate further including a connecting portion extending between the first section and the second section, the connecting portion having first and second ends and a thickness extending from the first surface to the second surface, the first surface and the second surface being arranged on opposite sides of the connecting portion of the semiconductor substrate, the first end of the connecting portion having the first thickness and being connected to the first section and the second end of the connecting portion having the second thickness and being connected to the second section, and the thickness of the connecting portion gradually tapering from the first thickness at the first end to the second thickness at the second end;
• a plurality of isolation trenches penetrating the semiconductor substrate from the first surface to the second surface for defining a plurality of element-forming regions therebetween, the connecting portion extending between a first isolation trench and a second isolation trench and being completely isolated from the first section and the second section by the isolation trenches penetrating the semiconductor substrate from the first surface to the second surface, a part of the plurality of element-forming regions provided in the first section and another part of the plurality of element-forming regions provided in the second section;
• and
• a plurality of elements located at respective ones of the plurality of element-forming regions, the plurality of elements including a double-sided electrode element that includes a pair of electrodes separately disposed on the first surface and the second surface, the double-sided electrode element being located in the second section, and the plurality of elements including a vertical passive element that includes one of a diode, a resistor and a wiring element.

A method of manufacturing a semiconductor device, comprising steps of:

• preparing a semiconductor substrate having a first surface and a second surface and including a plurality of sections having different thicknesses between the first surface and the second surface, the plurality of sections including a first section having a first thickness and a second section having a second thickness, the second section being a thinnest section in the plurality of sections, the first thickness being greater than the second thickness, and
• forming a connecting portion from the semiconductor substrate that extends between the first section and the second section, the connecting portion having first and second ends and a thickness extending from the first surface to the second surface, the first end of the connecting portion having the first thickness and being connected to the first section and the second end of the connecting portion having the second thickness and being connected to the second section, and the thickness of the connecting portion tapering from the first thickness at the first end to the second thickness at the second end;
• forming a plurality of isolation trenches penetrating the semiconductor substrate from the first surface to the second surface for defining a plurality of element-forming regions therebetween, the plurality of isolation trenches including a first isolation trench penetrating the first section and a second isolation trench penetrating the second section, the connecting portion extending between the first isolation trench and the second isolation trench and being completely isolated from the first section and the second section by the isolation trenches penetrating the semiconductor substrate from the first surface to the second surface, a part of the plurality of element-forming regions provided in the first section and another part of the plurality of element-forming regions provided in the second section;
• and
• forming a plurality of elements located at respective ones of the plurality of element-forming regions, the plurality of elements including a first element located in the first section and a second element located in the second section, the first element and the second element having different breakdown voltages, the second element including a double-sided electrode element that includes a pair of electrodes separately disposed on the first surface and the second surface, and the plurality of elements including a vertical passive element that includes one of a diode, a resistor and a wiring element.