KR20110025499A

KR20110025499A - Fabricating method of photo resist pattern

Info

Publication number: KR20110025499A
Application number: KR1020090083599A
Authority: KR
Inventors: 이병호
Original assignee: 주식회사 동부하이텍
Priority date: 2009-09-04
Filing date: 2009-09-04
Publication date: 2011-03-10

Abstract

In another embodiment, a method of forming a photoresist pattern may include forming a phase change material layer on a semiconductor substrate; Injecting energy into an area of the phase change material layer corresponding to a desired photoresist pattern using an energy scanning device; Forming a photoresist layer on the phase change material layer; And exposing the entire surface of the photoresist layer.

By using the reflection characteristics of the phase change material, it is possible to secure a stable process margin, to realize a fine line width, and to solve problems of a photolithography process such as a bridge phenomenon. In addition, there is an effect that can easily adjust the critical line width and thickness of the photoresist pattern.

Description

Fabrication method of photo resist pattern

An embodiment relates to a method of forming a photoresist pattern.

In order to fabricate semiconductor devices having a line width of several tens of nm, for example, 50 nm to 60 nm, photolithography processes satisfying various resolution enhancement technologies (RETs) are essential.

For example, there is a method of directly forming a photoresist pattern having a fine line width using a Phase Shift Mask (PSM) and ArF (Argon Fluoride) light source to which Chromeless Phase Lithography (CPL) technology is applied.

The ArF light source has a short wavelength of about 193 nm, and when used in an immersion type equipment, the wavelength may be further shortened by the refractive index of pure water, so that the photoresist pattern having a fine line width may be engraved.

In addition, there is a double exposure method using a binary mask and an alternating PSM.

However, this method requires expensive exposure equipment and expensive masks with high magnification NA (oral ratio), and the processing is complicated and the probability of defects is high.

In addition, the immersion ArF exposure equipment is about five times more expensive than the KrF (Frexed Krypton) exposure equipment, and the CPL mask takes about 10 times more manufacturing cost than the general mask.

In particular, CPL masks are very difficult to fabricate and have a high probability of generating defects on the mask, making it difficult to apply them to circuit implementation of semiconductor devices.

The embodiment provides a method of forming a photoresist pattern capable of fabricating a photoresist pattern having a fine line width using general exposure equipment without using expensive equipment having a special function.

In addition, the embodiment provides a method of forming a photoresist pattern capable of realizing a fine line width while at the same time securing a stable process margin by using the reflection characteristics of the phase change material.

According to the embodiment, the following effects are obtained.

First, a photoresist pattern having a fine line width of 65 nm or less may be manufactured using general exposure equipment without using expensive equipment having a special function.

Second, by using the reflection characteristics of the phase change material, it is possible to secure a stable process margin, to realize a fine line width, and to solve problems of a photolithography process such as a bridge phenomenon. In addition, there is an effect that can easily adjust the critical line width and thickness of the photoresist pattern.

Third, there is no need to provide expensive exposure equipment and masks, thereby improving process efficiency, reducing defect rates, and reducing production costs.

A method of forming a photoresist pattern according to an embodiment will be described in detail with reference to the accompanying drawings.

Hereinafter, in describing the embodiments, detailed descriptions of related well-known functions or configurations are deemed to unnecessarily obscure the subject matter of the present invention, and thus only the essential components directly related to the technical spirit of the present invention will be referred to. .

1 is a view schematically illustrating a process of patterning a phase change material layer 100 in a method of forming a photoresist pattern according to an embodiment, and FIG. 2 is a phase change material layer in a method of forming a photoresist pattern according to an embodiment. It is a side sectional view which partially shows the pattern of (100).

Phase Change Material (PCM) refers to a material that changes its state by energy sources such as laser, ions, visible light, electricity, and heat. Representative phase change materials used in semiconductor processes include GeSbTe, GeTe, SbTe, etc. are mentioned.

Such a phase change material is amorphous when it is not energized, has an increase in resistance, diffuse reflection of light, and the like.

In addition, the phase change material may be crystalline when subjected to energy, have low resistance, and may have specular reflectance of light. In other words, it can be said that the phase change material receiving the energy is in a state similar to that of the metal material.

First, the phase change material layer 100 is formed by depositing a phase change material on a semiconductor substrate (not shown) that requires a photolithography process such as an ion implantation process or an etching process.

The semiconductor substrate may be a substrate on which a metal wiring layer, an insulating layer, a gate electrode layer, an ion implantation layer, and the like are formed, and the phase change material may be deposited using a method such as sputtering or chemical vapor deposition (CVD).

Next, using an energy scanning device, as described above, energy such as laser, ions, visible light, electricity, and heat is scanned into the phase change material layer 100.

In this case, the energy is scanned such that the scanning region of the phase change material layer 100 and the pattern region to be formed on the subsequent photoresist layer (see FIG. 3) 200 are the same.

The embodiment is intended to form a nano-pattern fine pattern on the photoresist layer, so that a laser scanning device, an electron injection device, an ion implantation device, etc., which are easy to scan along the pattern shape and can implement a fine line pattern, are used. It is good.

As such, as illustrated in FIG. 1, an energy injection region 120 (hereinafter referred to as an “energy injection region”) and an energy injection region (not shown) are illustrated in FIG. 1 through an energy injection process. 110 " energy non-injection region "

The energy injection region 120 functions similarly to the metal layer as described above, and the energy non-injection region 110 functions similarly to the nonmetal layer.

Therefore, as shown in FIG. 2, the energy injection region 120 vertically reflects light incident from the upper side, and the energy non-injection region 110 diffusely reflects light incident from the upper side at various angles.

3 is a view schematically illustrating a process of patterning the photoresist layer 200 in the method of forming the photoresist pattern according to the embodiment.

Next, a photoresist material is coated on the phase change material layer 100 to form a photoresist layer 200.

When the photoresist layer 200 is formed, an exposure process is performed on the entire surface of the semiconductor substrate.

The light used for exposure passes through the photoresist layer 200 firstly, exposes the photoresist layer 200 as a whole, and reaches the phase change material layer 100 disposed thereunder.

Among the light reaching the phase change material layer 100, the light reaching the energy injection region 120 is mostly totally reflected to the upper side to expose the photoresist layer 200 to the second exposure.

On the other hand, the light reaching the energy non-injection region 110 among the light reaching the phase change material layer 100 is diffusely reflected and is mostly concentrated outside the photoresist layer 200.

Therefore, the second exposed region of the photoresist layer 200 has a shape in which the pattern of the energy injection region 120 of the phase change material layer 100, that is, the phase change material layer 100 is transferred as it is. do.

Next, when the development process is performed, only the secondary exposure area of the photoresist layer 200 is removed, and the photoresist pattern is completed.

Thereafter, an ion implantation process, an etching process, and the like may be performed, and the photoresist layer 200 and the phase change material layer 100 may be removed.

For reference, the energy scanning region may be reversed depending on whether the material of the photoresist layer 200 is a positive type material or a negative type material.

For example, depending on the type of the photoresist material, the energy is injected into the region of the phase change material layer 100 corresponding to the photoresist pattern to be implemented or vice versa in the region of the phase change material layer 100. The energy can be injected.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be understood that various modifications and applications other than those described above are possible. For example, each component specifically shown in the embodiments of the present invention can be modified and implemented. And differences relating to such modifications and applications will have to be construed as being included in the scope of the invention defined in the appended claims.

1 is a view schematically illustrating a process of patterning a phase change material layer in a method of forming a photoresist pattern according to an embodiment.

2 is a side cross-sectional view partially showing a pattern of a phase change material layer in a method of forming a photoresist pattern according to an embodiment.

3 is a view schematically illustrating a process of patterning a photoresist layer in a method of forming a photoresist pattern according to an embodiment.

Claims

Forming a phase change material layer on the semiconductor substrate;

Injecting energy into an area of the phase change material layer corresponding to a desired photoresist pattern using an energy scanning device;

Forming a photoresist layer on the phase change material layer; And

And exposing the entire surface of the photoresist layer.

The method of claim 1, wherein the phase change material constituting the phase change material layer

A method of forming a photoresist pattern comprising at least one of GeSbTe, GeTe, and SbTe.

The method of claim 1, wherein the phase change material layer

A method of forming a photoresist pattern, wherein the phase change material is deposited by any one of a sputtering method and a CVD method.

The energy injection device of claim 1, wherein

A method of forming a photoresist pattern, comprising injecting energy of at least one of laser, ions, visible light, electrons and heat.

The method of claim 1,

And after the exposure process is processed, the developing process is further processed.

The method of claim 1,

And removing the photoresist layer and the phase change material layer.

The method of claim 1, wherein injecting energy

And the injecting and non-injecting regions of the energy are inverted according to the photosensitive type of the photoresist layer.

The method of claim 1, wherein the semiconductor substrate

A method of forming a photoresist pattern comprising at least one layer of an etching target layer and an ion implantation target layer requiring a photolithography process.