Semiconductor device and method of manufacturing the same
A MOSFET that has a drain region and a source region on an upper surface of a semiconductor substrate and a gate electrode that is formed on the semiconductor substrate, and an element separation insulating film that includes an opening portion which exposes an active region, on the semiconductor substrate, are formed. At this point, a gate leading-out interconnection that overlaps the element separation insulating film when viewed from above, and that is integrally combined with the gate electrode is formed in a position where the gate leading-out interconnection does not extend over a distance between both the drain region and the source region when viewed from above, on a region that is exposed from the gate electrode.
1. A semiconductor device comprising:
a semiconductor substrate;
a source region and a drain region that are formed on an upper surface of the semiconductor substrate and are adjacent to each other in a first direction;
an element separation insulating film that is formed on the semiconductor substrate and exposes a portion of a first region which is the upper surface of the semiconductor substrate between both the source region and the drain region;
a gate electrode that is formed on a region over the first region, a portion of the drain region and a portion of the source region;
a gate insulating film thinner than the element separation insulating film and the gate electrode;
a gate leading-out interconnection that is integrally connected to the gate electrode and is formed on the element separation insulating film; and
a well that is formed on an upper surface of the semiconductor substrate,
wherein a portion of the element separation insulating film abuts the well,
wherein the gate electrode, the source region, and the drain region constitute a field effect transistor,
wherein the gate leading-out interconnection is separated from one of the source region and the drain region in plan view,
wherein a first side, a second side and a third side of the source region is surrounded by the well in plan view, and a first side, a second side and a third side of the drain region is surrounded by the well in plan view,
wherein a fourth side of the source region is electrically connected to a drain electrode and a fourth side of the drain region is electrically connected to a source electrode, and
wherein the fourth side of the source region is electrically connected to the drain electrode via a plug and the fourth side of the drain region is electrically connected to the source electrode via a second plug.
2. The semiconductor device according to claim 1 ,
wherein the gate leading-out interconnection is separated from the source region when viewed from above.
3. The semiconductor device according to claim 1 , further comprising:
a well that is formed on the upper surface of the semiconductor substrate and on an upper surface of which the source region and the drain region are formed; and
a first semiconductor region that is formed on the first region which overlaps an end portion in a gate width direction of the gate electrode when viewed from above, and that has a higher concentration of impurities than the well,
wherein the well and the first semiconductor region have different conductivity than the source region and the drain region.
4. The semiconductor device according to claim 3 ,
wherein the first semiconductor region is electrically connected to the source region.
5. The semiconductor device according to claim 3 , further comprising:
a first electrode that is formed right over the first semiconductor region with the element separation insulating film in between,
wherein the same electric potential as is applied to the first semiconductor region is applied to the first electrode.
6. The semiconductor device according to claim 4 , further comprising:
a source electrode that is formed right over the first semiconductor region with the element separation insulating film in between, and is electrically connected to the source region.
7. The semiconductor device according to claim 3 , further comprising:
an element separation region that is formed on the upper surface of the semiconductor substrate, and is a second semiconductor region that surrounds the well, the source region, and the drain region when viewed from above,
wherein the element separation region has the same conductivity as the well, and
wherein the element separation region and the first semiconductor region are in contact with each other.
8. The semiconductor device according to claim 1 ,
wherein a length of the gate leading-out interconnection is smaller in a gate length direction of the gate electrode than a length of the gate electrode.
9. The semiconductor device according to claim 1 ,
wherein the semiconductor substrate is made of a material that has a wider band gap than silicon.
10. The semiconductor device according to claim 1 , wherein
the source region and the drain region are formed from an upper surface of the well to a middle of a depth of the well.
11. The semiconductor device according to claim 10 , wherein the well separates the source region and the drain region.
12. The semiconductor device according to claim 1 , further comprising:
an element separation region that is formed on the upper surface of the semiconductor substrate and in the well.
13. The semiconductor device according to claim 12 , wherein
the element separation region that is formed on the upper surface of the semiconductor substrate and surrounds the source region and the drain region.