Semiconductor device having junction termination extension

A semiconductor device comprising:

• a semiconductor substrate;
• an n-type SiC drift layer formed in said semiconductor substrate;
• an electrode formed on said semiconductor substrate to come into Schottky contact with said n-type SiC drift layer;
• and
• a p-type Junction Termination Extension region formed in an upper portion of said n-type SiC drift layer under an edge of said electrode which is in contact with said semiconductor substrate, wherein
• said Junction Termination Extension region has a charge level continuously decreasing outwardly from said edge, said charge level ranging from 1.8×1013 to 4×1013 cm−2 under said edge and ranging from 1×1013 to 2.5×1013 cm−2 in a position 15 μm outwardly away from said edge, and
• said Junction Termination Extension region has a constant thickness and an impurity concentration per unit volume continuously decreasing outwardly from said edge.

A semiconductor device comprising:

• a semiconductor substrate;
• an n-type SiC drift layer formed in said semiconductor substrate;
• an electrode formed on said semiconductor substrate to come into Schottky contact with said n-type SiC drift layer;
• and
• a p-type Junction Termination Extension region formed in an upper portion of said n-type SiC drift layer under an edge of said electrode which is in contact with said semiconductor substrate, wherein
• said Junction Termination Extension region has a charge level continuously decreasing outwardly from said edge, said charge level ranging from 1.8×1013 to 4×1013 cm−2 under said edge and ranging from 1×1013 to 2.5×1013 cm−2 in a position 15 μm outwardly away from said edge, and
• said Junction Termination Extension region has a constant impurity concentration per unit volume and a thickness continuously decreasing outwardly from said edge.