SiC semiconductor device having a high mobility and a high threshold voltage, inverter circuit, and vehicle
A semiconductor device including a p-type SiC layer, a gate electrode, and a gate insulating layer therebetween, the gate insulating layer including a first layer, a second layer provided between the first layer and the gate electrode and having a higher oxygen density than the first layer, a first and second regions provided in the second layer, the first region including a first element (at least one of Ta, Nb and V) having a first concentration peak, and the second region including a second element (at least one of Ge, B, Al, Ga, In, Be, Mg, Ca, Sr, Ba , La, and lanthanoid) having a second concentration peak of the second element and a third concentration peak of C, a distance between the second concentration peak and the third concentration peak being shorter than a distance between the first concentration peak and the third concentration peak.
1. A semiconductor device, comprising:
a p-type SiC layer;
a gate electrode; and
a gate insulating layer provided between the SiC layer and the gate electrode, the gate insulating layer including:
a first layer,
a second layer provided between the first layer and the gate electrode, the second layer having a higher oxygen density than the first layer,
a first region provided in the second layer, the first region including a first element which is at least one element in the group of Ta (tantalum), Nb (niobium), and V (vanadium) and the first region having a first concentration peak of the first element; and
a second region provided in the first layer, the second region including a second element which is at least one element in the group of Ge (germanium), B (boron), Al (aluminum), Ga (gallium), In (indium), Be (beryllium), Mg (magnesium), Ca (calcium), Sr (strontium), Ba (barium), La (lantern), and lanthanoid (Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) and the second region having a second concentration peak of the second element and a third concentration peak of C (carbon), a distance between the second concentration peak and the third concentration peak being shorter than a distance between the first concentration peak and the third concentration peak.
2. The semiconductor device according to claim 1 , wherein a distance between the second concentration peak and the first concentration peak is equal to or less than 4 nm, and the distance between the first concentration peak and the third concentration peak is equal to or less than 4 nm.
3. The semiconductor device according to claim 1 , wherein full widths at half maximum of the first concentration peak and the second concentration peak are equal to or less than 1 nm.
4. The semiconductor device according to claim 1 , wherein a full width at half maximum of the third concentration peak is equal to or less than 1 nm.
5. The semiconductor device according to claim 1 , wherein the first layer is a silicone oxide film.
6. The semiconductor device according to claim 1 , wherein the second layer is a hafnium oxide film or a zirconium oxide film.
7. A semiconductor device, comprising:
a p-type SiC layer;
a gate electrode; and
a gate insulating layer provided between the SiC layer and the gate electrode, the gate insulating layer including:
a first layer,
a second layer provided between the first layer and the gate electrode, the second layer having a lower oxygen density than the first layer,
a first region provided across the first layer and the second layer, the first region including a first element which is at least one element in the group of N (nitrogen), P (phosphorus), As (arsenic), Sb (antimony), and Bi (bismuth) and the first region having a first concentration peak of the first element, and
a second region provided in the second layer, the second region including a second element which is at least one element in the group of N (nitrogen), P (phosphorus), As (arsenic), Sb (antimony), and Bi (bismuth) and the second region having a second concentration peak of the second element and a third concentration peak of C (carbon), a distance between the second concentration peak and the third concentration peak being shorter than a distance between the first concentration peak and the third concentration peak.
8. The semiconductor device according to claim 7 , wherein a distance between the second concentration peak and the first concentration peak is equal to or less than 4 nm, and the distance between the first concentration peak and the third concentration peak is equal to or less than 4 nm.
9. The semiconductor device according to claim 7 , wherein full widths at half maximum of the first concentration peak and the second concentration peak are equal to or less than 1 nm.
10. The semiconductor device according to claim 7 , wherein a full width at half maximum of the third concentration peak is equal to or less than 1 nm.
11. The semiconductor device according to claim 7 , wherein the second layer is a silicone oxide film.
12. The semiconductor device according to claim 7 , wherein the first layer is a hafnium oxide film or a zirconium oxide film.
13. An inverter circuit, comprising the semiconductor device according to claim 1 .
14. A vehicle comprising the semiconductor device according to claim 1 .
15. An inverter circuit, comprising the semiconductor device according to claim 7 .
16. A vehicle comprising the semiconductor device according to claim 7 .