| 摘要 |
<p>PURPOSE:To prevent the lowering of reverse breakdown voltage while further reducing low forward threshold voltage, and to maintain high-speed switching characteristics by forming a Schottky barrier using a metal having low barrier height and a Schottky barrier employing a metal having high barrier height onto the same semiconductor substrate. CONSTITUTION:A silicon substrate, in which an (n) layer 2 is grown on an n<+> substrate in an epitaxial manner, is used, and a p<+> region 3 is formed in a slender square annular shape. A large square annular p<+> guard ring 4 is shaped while simultaneously surrounding the outer circumference of the substrate. A titanium layer 5 is brought into contact with approximately the halves of the surfaces of the p<+> annular regions 3 and the exposed surfaces of the (n) layer 2 surrounded by the approximately halves of the surfaces of the regions 3, and a molybdenum layer 6 is brought into contact on the residual halves of the surfaces of the p<+> regions 3, the exposed surface of the (n) layer 2 surrounding the p<+> regions 3 and the half of the surface of the guard ring 4. The barrier height of titanium is 0.5eV, and is lower than the 0.66eV of molybdenum. Accordingly, a diode having low forward threshold voltage and high reverse breakdown voltage is acquired.</p> |
