Ohmic electrode

7:

• An ohmic electrode, comprising:
• an ohmic contact layer formed on a SiC semiconductor layer, the ohmic contact layer comprising a material selected from the group consisting of nickel and nickel silicide;
• a barrier layer formed on the ohmic contact layer;
• and
• an electrode layer formed on the barrier layer, the electrode layer comprising a copper alloy comprising at least one selected from the group consisting of zinc, nickel, titanium, manganese, and calcium,
• wherein the barrier layer comprises an element that forms no solid solution with copper or an element that forms a compound with copper, and
• wherein the barrier layer comprises a material selected from the group consisting of molybdenum, tantalum, tungsten, niobium, titanium, and a nitride thereof.

8:

• The ohmic electrode according to claim 7,
• wherein the copper alloy comprises at least one selected from the group consisting of
• zinc in an amount of 0.1 at % or more and 3 at % or less;
• nickel in an amount of 0.1 at % or more and 3 at % or less;
• titanium in an amount of 0.1 at % or more and 0.5 at % or less;
• manganese in an amount of 0.1 at % or more and 1 at % or less, and
• calcium in an amount of 0.1 at % or more and 1 at % or less.