Method of forming structure having surface roughness due to...

Details Method of forming structure having surface roughness due to... Method of forming structure having surface roughness due to...

2001-01-05

2002-10-22

Utech, Benjamin L. (Department: 1765)

Semiconductor device manufacturing: process

Chemical etching

Vapor phase etching

C438S710000, C438S712000, C438S713000

Reexamination Certificate

active

06468916

ABSTRACT:

This application claims priority under 35 U.S.C. §§ 119 and/or 365 to Korean Application No. 00-363 filed Jan. 5, 2000; the entire content of which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method of forming a micro structure having nano-sized surface features.
2. Description of the Related Art
Forming a micro structure requires precise fabrication technologies since the micro structure includes a plurality of miniaturized electronic components. Generally, a thin film is grown and formed on one substrate and physicochemically cut in a predetermined pattern at a specific step to obtain a micro structure having a desired structure. In some cases, a micro structure is formed by growing and forming thin films on two substrates, cutting them in predetermined patterns, and combining the two substrates into one.
Typically, a patterning process such as photolithography or plasma etching is applied to form a regularly-structured micro structure. Sometimes a micro structure having an irregular shape with a nano- or micro-sized features may be required. However, since conventional etching techniques are chiefly applied to regularly-shaped micro structures, it is difficult to obtain micro structure having an irregular shape with a nano- or micro-sized features.
For example, it is known that a micro tip having more edges, which is an electron emission source of a field emission display, is advantageous in electron emission over that a micro chip having a single electron emission edge, but effective fabrication techniques therefor has been not yet proposed.
Micro structures other than the micro tip may also require a structure having an irregular shape of a micro scale or a nano scale.
SUMMARY OF THE INVENTION
To solve the above problems, it is an objective of the present invention to provide a method of forming a micro structure having surface roughness due to nano-sized surface features.
Accordingly, to achieve the above objective, the present invention provides a method of forming a micro structure having surface roughness due to nano-sized surface features. The method includes the steps of forming a micro structure having predetermined size and shape on a substrate; coating a carbon polymer layer on the substrate including the micro structure to a predetermined thickness; performing a first etch on the carbon polymer layer by means of plasma etching using a reactive gas in which O
2
gas for etching the carbon polymer layer and a gas for etching the micro structure are mixed and forming a mask layer by the residual carbon polymer layer on the surface of the micro structure, and performing a second etch by means of plasma etching using the mixed reactive gas to remove the mask layer and etch the surface of the micro structure not covered by the mask layer so that the micro structure has nano-sized surface features.
Preferably, the carbon polymer layer is formed of polyimide or photoresist, and etched using reactive ion etching (RIE).
When etching the carbon polymer layer, the reactive gas is preferably composed of O
2
as a main component and at least one of fluorine-family gases such as CF
4
, SF
6
and CHF
3
or composed of O
2
as a main component and at least one of chlorine-family gases such as Cl
2
and CCl
4
. In particular, if the reactive gas contains fluorine-family gas, at least one of CF
4
/O
2
, SF
6
/O
2
, CHF
3
/O
2
, CF
4
/SF
6
/O
2
, CF
4
/CHF
3
/O
2
, and SF
6
/CHF
3
/O
2
is preferably applied. If the reactive gas contains chlorine-family gas, at least one of Cl
2
/O
2
, CCl
4
/O
2
, and Cl
2
/CCl
4
/O
2
is applied.
In etching the micro structure, an etch rate is preferably adjusted by at least one of plasma power, the O
2
content of the reactive gas with respect to the etch gas for etching the micro structure and a plasma process pressure, thereby controlling the surface roughness of the micro structure.


REFERENCES:
patent: 4642163 (1987-02-01), Greschner et al.
patent: 5578185 (1996-11-01), Bergeron et al.
patent: 5637189 (1997-06-01), Peeters et al.
patent: 6193870 (2001-02-01), Morse et al.
Yue Kuo, “Factors Affecting the Molybdenum Line Slope By Reactive Ion Etching”,Journal of the Electrochemical Society, Electrochemical Society, Manchester, Jun. 1, 1990, pp. 1907-1911, vol. 137, No. 6, New Hampshire.

Affiliated with

Also associated with

Rating

Method of forming structure having surface roughness due to... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method of forming structure having surface roughness due to..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of forming structure having surface roughness due to... will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2930943