Diode and manufacturing method thereof
Disclosed are a diode and a manufacturing method thereof. The diode includes: a first substrate, the first substrate being an N-type doped substrate with a doping concentration equal to or greater than 1×10 18 cm −3 ; a metal atomic layer located on a first surface of the first substrate; an epitaxial structure located on the metal atomic layer; a first electrode located on the epitaxial structure; and a second electrode located on a second surface, opposite to the first surface, of the first substrate. The diode significantly reduces forward conduction voltage drop.
1 . A diode, comprising:
a first substrate, the first substrate being an N-type doped substrate with a doping concentration equal to or greater than 1×10 18 cm −3 ;
a metal atomic layer located on a first surface of the first substrate;
an epitaxial structure located on the metal atomic layer, wherein the epitaxial structure is in direct contact with the metal atomic layer;
a first electrode located on the epitaxial structure; and
a second electrode located on a second surface, opposite to the first surface, of the first substrate.
2 . The diode according to claim 1 , wherein the epitaxial structure comprises:
an N-type semiconductor layer; and
a P-type semiconductor layer located on the N-type semiconductor layer.
3 . The diode according to claim 2 , wherein the epitaxial structure further comprises: an intrinsic semiconductor layer located between the N-type semiconductor layer and the P-type semiconductor layer.
4 . The diode according to claim 2 , wherein the N-type semiconductor layer comprises a groove, and the P-type semiconductor layer is located in the groove.
5 . The diode according to claim 2 , wherein a doping concentration of the N-type semiconductor layer is equal to or greater than 1×10 18 cm −3 .
6 . The diode according to claim 2 , wherein the N-type semiconductor layer is a lightly doped semiconductor layer, and the P-type semiconductor layer is a heavily doped semiconductor layer.
7 . The diode according to claim 2 , wherein the N-type semiconductor layer and the P-type semiconductor layer have a single-layer structure or a multi-layer structure.
8 . The diode according to claim 1 , wherein the first substrate has at least one pattern.
9 . The diode according to claim 1 , wherein the metal atomic layer has a pattern, and the pattern is a continuous pattern or a discontinuous pattern.
10 . The diode according to claim 1 , wherein a material of the metal atomic layer is one of Al and Mg.
11 . The diode according to claim 1 , wherein a contact manner between the first electrode and the epitaxial structure comprises a Schottky contact.
12 . The diode according to claim 1 , wherein the second electrode is in ohmic contact with the first substrate.
13 . The diode according to claim 1 , further comprising: a second substrate located between the first substrate and the second electrode, wherein the second substrate is an N-type doped substrate with a doping concentration less than 1×10 18 cm −3 , and the second electrode is in ohmic contact with the second substrate.
14 . The diode according to claim 2 , wherein the N-type semiconductor layer and the P-type semiconductor layer are semiconductor layers made of one or more materials of GaN, AlN, AlGaN, InGaN, InN, InAlGaN and AlInN.
15 . The diode according to claim 1 , wherein the first electrode and the second electrode are both single-layer metal or multi-layer mixed metal.
16 . The diode according to claim 1 , further comprising: a passivation layer located on the epitaxial structure, wherein the passivation layer is formed by one or a combination of aluminum nitride, silicon dioxide, silicon oxynitride and aluminum oxide.
17 . The diode according to claim 1 , wherein the diode is a vertical structure light emitting diode, and a horizontal width of the vertical structure light emitting diode is less than 500 um.
18 . The diode according to claim 17 , wherein the horizontal width of the vertical structure light emitting diode is less than 100 um.
19 . A manufacturing method of a diode, comprising:
forming a metal atomic layer on a first surface of a first substrate, the first substrate being an N-type doped substrate with a doping concentration equal to or greater than 1×10 18 cm −3 ;
forming an epitaxial structure on the metal atomic layer, wherein the epitaxial structure is in direct contact with the metal atomic layer;
forming a first electrode on the epitaxial structure; and
forming a second electrode on a second surface, opposite to the first surface, of the first substrate.