Post structure, semiconductor device and light emitting device using the structure, and method for forming the same

Abstract

A nanometer-scale post structure and a method for forming the same are disclosed. More particularly, a post structure, a light emitting device using the structure, and a method for forming the same, which is capable of forming a nanometer-scale post structure having a repetitive pattern by using an etching process, are disclosed. The method includes forming unit patterns on a substrate by use of a first material, growing a wet-etchable second material on the substrate formed with the unit patterns, and wet etching the substrate having the grown second material.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principle of the invention. In the drawings:

FIGS. 1 to 10 are views illustrating a method for forming a post structure according to an embodiment of the present invention, in which;

FIG. 1 is a plan view illustrating unit patterns formed on a substrate;

FIG. 2 is a sectional view illustrating an example of unit patterns formed on the substrate;

FIG. 3 is a sectional view illustrating another example of unit patterns formed on the substrate;

FIG. 4 is a plan view illustrating a second material formed over the unit patterns;

FIG. 5 is a sectional view of FIG. 4;

FIG. 6 is a plan view illustrating an interfacing process of the second material;

FIG. 7 is a sectional view of FIG. 6;

FIG. 8 is an electron microscope photograph illustrating the interfaced second material;

FIG. 9 is an electron microscope photograph illustrating an initial etching stage; and

FIG. 10 is an electron microscope photograph illustrating a post structure;

FIG. 11 is a side view illustrating a post structure according to an embodiment of the present invention;

FIG. 12 is a sectional view illustrating a manufacturing procedure of a light emitting device having the post structure according to the present invention;

FIG. 13 is a sectional view of the light emitting device having the post structure according to an embodiment of the present invention;

FIGS. 14 to 16 are sectional views illustrating a process for forming a capacitor for use in a memory device using the post structure according to the present invention, in which;

FIG. 14 is a sectional view illustrating an oxide post structure;

FIG. 15 is a sectional view illustrating poly silicone formed over the post structure; and

FIG. 16 is a sectional view illustrating the capacitor for the memory device.

Claims

1. A method for forming a post structure comprising: forming unit patterns on a substrate by use of a first material;growing a wet-etchable second material on the substrate formed with the unit patterns; andwet etching the substrate having the grown second material.

2. The method according to claim 1, wherein the formation of the unit patterns comprises: forming a first material layer over the substrate; andetching the first material layer, to form the unit patterns.

3. The method according to claim 1, wherein the growth of the second material is performed at least until the second materials, which begin to be grown over the adjacent unit patterns, come into contact with each other to thereby form an interface.

4. The method according to claim 1, wherein the wet etching of the substrate is performed until the substrate is exposed.

5. A method for forming a semiconductor device comprising: forming unit patterns on a substrate by use of a first material;growing a wet-etchable second material on the substrate formed with the unit patterns;wet etching the substrate having the grown second material, to form a post structure;forming a third material layer over the post structure;etching a plane formed with the third material layer; andremoving at least a part of the post structure.

6. The method according to claim 5, wherein the substrate is a silicon substrate.

7. The method according to claim 5, wherein the post structure is made of an oxide.

8. The method according to claim 5, wherein the third material layer is made of polycrystalline silicon.

9. The method according to claim 5, wherein the etching of the plane formed with the third material layer is performed until the post structure is exposed.

10. A method for forming a light emitting device comprising: forming unit patterns on a substrate by use of a first material;growing a wet-etchable second material on the substrate formed with the unit patterns;wet etching the substrate having the grown second material, to form a post structure;forming a semiconductor layers having multi-layer structure on the substrate formed with the post structure;forming a first electrode on the semiconductor layers;removing the substrate; andforming a second electrode on the semiconductor layers that is exposed after removing the substrate.

11. The method according to claim 10, further comprising: after the formation of the first electrode, forming a supporting layer having a metallic element or a semiconductor including Si on the first electrode.

12. A post structure comprising: a substrate;unit patterns formed on the substrate by use of a first material; anda plurality of polygonal posts connected to the unit patterns, respectively, the posts being made of a second material.

13. The post structure according to claim 12, wherein each of the posts has a lower end portion having a smaller diameter than a diameter of the post.

14. The post structure according to claim 13, wherein the smaller diameter portion is located between the unit pattern and the post.

15. The post structure according to claim 12, wherein the first material is the same material as a constituent material of the substrate.

16. The post structure according to claim 12, wherein a vertical cross section of each unit pattern has any one shape selected from among an arc shape, a partial elliptical shape, and a trapezoidal shape.

17. The post structure according to claim 12, wherein the second material is an oxide or nitride.

18. A light emitting device comprising: a plurality of semiconductor layers having a first plane and a second plane;a plurality of posts periodically arranged at the first plane of the semiconductor layers, each post having a protrusion protruded from the first plane;a first electrode located on the second plane of the semiconductor layers; anda second electrode located on the first plane of the semiconductor layers.

19. The light emitting device according to claim 18, wherein a vertical cross section of the protrusion of each post has any one shape selected from among an arc shape, a partial elliptical shape, and a trapezoidal shape.

20. The light emitting device according to claim 18, wherein the protrusion has an inclined surface.

21. The light emitting device according to claim 18, wherein the first electrode comprises: an ohmic electrode; anda reflective electrode located on the ohmic electrode.

22. The light emitting device according to claim 18, wherein a supporting layer having a metallic element or a semiconductor including Si is formed on the first electrode.

23. The light emitting device according to claim 18, wherein the semiconductor layers comprise: a first conductive semiconductor layer;a light emitting layer located on the first conductive semiconductor layer; anda second conductive semiconductor layer located on the light emitting layer.

24. The light emitting device according to claim 18, wherein the plurality of posts are located such that at least a part of each post is located in one of the semiconductor layers.

25. The light emitting device according to claim 18, wherein the plurality of posts are made of a dielectric material.

26. The light emitting device according to claim 18, wherein each of the posts has a lower end portion having a smaller diameter than a diameter of the post.