KR20150035247A

KR20150035247A - Showerhead

Info

Publication number: KR20150035247A
Application number: KR20130115574A
Authority: KR
Inventors: 권성구
Original assignee: 군산대학교산학협력단
Priority date: 2013-09-27
Filing date: 2013-09-27
Publication date: 2015-04-06

Abstract

The present invention relates to a showerhead for spraying a gaseous raw material into a chamber of a chemical vapor deposition apparatus in a semiconductor device manufacturing process, and a thin film apparatus having the same, wherein the showerhead plasma- Since the radicals and the organic metal precursors are injected into the injection space through separate passages, damage of the organic metal precursor due to contact with the radicals can be prevented and the loss of the plasma can be minimized by controlling the long- So that the metal thin film can be deposited uniformly, quickly, and efficiently.

Description

Showerhead {Showerhead}

The present invention relates to a showerhead for depositing a thin film on a substrate and a thin film device having the showerhead. More particularly, the present invention relates to a showerhead in which a thin film is improved in deposition efficiency by separately supplying and supplying a process gas and an organometallic gas, The present invention relates to a thin film device provided with a thin film transistor.

2. Description of the Related Art Recently, miniaturization of a semiconductor device has resulted in research and development of techniques for miniaturizing and increasing the degree of integration of patterns. Accordingly, it is difficult to form a metal layer having a multi-layer structure due to reduction of the size of the contact hole and deepening of the aspect ratio between the devices. In particular, since the conventional technique of embedding a metal in a contact hole by using a physical vapor deposition (PVD) method is difficult to apply, a new process technology for embedding a metal in a contact hole of a minute size need.

Accordingly, a process for forming a metal layer using metal organic chemical vapor deposition (MOCVD), which has excellent covering properties, has been developed to fabricate highly integrated and miniaturized semiconductor devices. However, the above process has a problem that the deposition rate is low and the productivity of the device is low, so that the manufacturing cost is high.

Therefore, a Plasma enhanced chemical vapor deposition (PECVD) method has been devised in which a plasma apparatus in which a reaction gas is activated and plasmaized to improve a deposition rate of a metal is introduced.

Plasma devices can be generally divided into a capacitive coupled plasma (CCP) type and an inductively coupled plasma (inductive coupled plasma) type according to a method of generating a plasma.

The plasma generated in the capacitively coupled plasma apparatus has an advantage of high ion energy accelerated by an electric field formed by itself. However, there is a problem that a thin film and a pattern formed on a substrate or a substrate are damaged by high energy ions, The degree of damage is great. On the other hand, the plasma formed in an inductively coupled plasma apparatus has a high density and forms a low ion energy distribution, which has the advantage of less damage to the substrate or thin film. However, the ion density of the plasma formed in the chamber is constant in the central region of the chamber, but is disadvantageous in that the uniformity of the ion density is lowered toward the edge region.

KOKAI Publication No. 1997-0003557 discloses a capacitively coupled plasma apparatus for generating a capacitive plasma including an upper reactor electrode and a lower reactor electrode located below the upper reactor electrode. Korean Patent No. 10-0963519 There is provided an inductively coupled plasma generating apparatus including a gas injecting unit for injecting a source gas into an upper portion of a chamber, an antenna to which a source power is applied, and an electrostatic chuck to which a bias power is applied, have.

A first problem to be solved by the present invention is to provide a shower head capable of minimizing the loss of plasma and delivering it onto a substrate.

A second object of the present invention is to provide a thin film deposition apparatus having the showerhead.

According to an aspect of the present invention, there is provided a thin film deposition apparatus including: a chamber having a space for performing a deposition process on a substrate; A susceptor capable of seating a substrate; And a showerhead.

The space portion where the deposition process is performed may be a spray space in which the plasma-treated process gas injected from the showerhead and the organometallic precursor are injected.

Wherein the showerhead may be positioned above the substrate and may be radial, square, or a variation thereof. The showerhead includes a plasma generator; A process gas inlet connected to the upper side of the plasma generator; And a jetting unit positioned below the plasma generating unit,

A plurality of first injection nozzles formed so as to penetrate through the ejection portion so that one end thereof communicates with the plasma generation portion and the other end opens into the ejection space; A precursor accommodating portion formed in the injection portion and containing an organometallic precursor supplied from the outside; And a plurality of second injection nozzles, one end of which is connected to the precursor accommodating portion and the other end of which is opened to the injection space.

A gas diffusion plate may be further provided between the plasma generating unit and the process gas inlet. The gas diffusion plate may be a plate having a plurality of holes formed densely.

The first injection nozzle may have a value obtained by dividing a width (diameter) by a length (height) of more than 0.05. Preferably, the value obtained by dividing the width by the length may be larger than 0.1 and smaller than 0.5, The value divided by the length may be greater than 0.2 and less than 0.3.

The width of the first injection nozzle may be 1-10 mm, and the width of the second injection nozzle may be 0.1-3 mm.

An electrode to which a high frequency power is supplied may be provided in the plasma generating unit. A process gas introduced into the plasma generating unit through the inlet may be converted into a plasma to generate radicals, And can be grounded to the top of the ejection plate.

The first injection nozzle and the second injection nozzle may be made of one or more materials selected from the group consisting of stainless steel, nickel, aluminum alloy and aluminum oxide, but are not limited thereto.

The precursor receiving portion may further include an organometallic gas inlet.

The thin film deposition apparatus according to the present invention may be a plasma induced chemical vapor deposition apparatus.

The thin film deposition apparatus according to the present invention may be a plasma-induced atomic layer deposition apparatus.

The thin film deposition apparatus having a showerhead according to the present invention is characterized in that the organic metal raw material to be injected and the radicals induced by the process gas are injected into the injection space through separate passages so that damage to the organic metal precursor due to contact with radicals (Aspect ratio) of the injection nozzle can be controlled to minimize the loss of the plasma and to be transferred to the injection space. Therefore, compared with the conventional chemical vapor deposition process, the metal can be uniformly, quickly, A thin film can be deposited.

1 is a cross-sectional view of a thin film deposition apparatus equipped with a showerhead according to an embodiment of the present invention.
FIG. 2 is an enlarged cross-sectional view of the spray nozzle of the shower head shown in FIG. 1. FIG.
3 is a plan view of a showerhead according to an embodiment of the present invention.
4 is a cross-sectional view of a spray plate provided in a showerhead according to an embodiment of the present invention.
5 is a sectional view of a capacitive coupled plasma thin film deposition apparatus according to another embodiment of the present invention.
6 is a cross-sectional view of a capacitive coupled plasma thin film deposition apparatus according to another embodiment of the present invention.
7 is a cross-sectional view of an internal inductively coupled plasma thin film deposition apparatus according to another embodiment of the present invention.
8 is a plan view of an electrode included in a thin film deposition apparatus according to an embodiment of the present invention.
9 is a plan view of a gas diffusion plate provided in a thin film deposition apparatus according to an embodiment of the present invention.
10 is a thin film deposition process diagram according to an embodiment of the present invention.
11 is a thin film deposition apparatus manufactured according to an embodiment of the present invention.
12 is a graph showing a difference in thickness deposited according to an RF power according to an embodiment of the present invention.
13 is a graph showing electrical characteristics of a thin film deposited according to an embodiment of the present invention.
FIG. 14 is a graph showing a deposition rate of a ZnO thin film according to a substrate temperature under a condition that a plasma power is applied at 150 watts according to an embodiment of the present invention. FIG.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to the drawings.

FIG. 1 is a cross-sectional view of a thin film deposition apparatus according to an embodiment of the present invention. FIG. 2 is an enlarged view of a first spray nozzle and a second spray nozzle of a shower head spraying unit provided in the thin film deposition apparatus shown in FIG. Sectional view of the unit.

1, 2, and 5 to 7, a thin film deposition apparatus according to the present invention includes a chamber 100 having a space in which a deposition process for a substrate is performed; A showerhead 200; And a susceptor 300 on which the substrate is mounted.

The showerhead 200 and the susceptor 300 are located inside the chamber 100. The chamber may further include an entrance door through which the substrate is loaded and unloaded for loading / unloading the substrate, and an exhaust port for exhausting the gas inside the chamber.

The susceptor may be formed in a flat plate shape where the substrate is seated.

The showerhead is configured to be capable of performing metal-organic chemical vapor deposition (MOCVD) or atomic layer deposition, and includes a plasma generator 230 ).

According to the present invention, the gas to be plasma-treated is preferably a process gas. When the precursor of the organometallic precursor is plasma-treated, the precursor is decomposed and the efficiency of the thin-film deposition reaction is rapidly lowered. The metal gas is preferably supplied without plasma treatment.

According to the present invention, the showerhead has a process inlet inlet 201 through which the process gas flows into the plasma generator 230, and a gas diffusion plate 210 is provided to uniformly supply the process gas. . The gas diffusion plate may have a plate shape in which a plurality of holes are densely formed.

The plasma generator may generate radicals by converting the process gas introduced through the inlet 201 into plasma. The plasma generating unit 230 includes high-frequency electrodes 231 and 232 and a power source unit 220.

A jetting unit 250 is formed below the plasma generating unit. The jetting unit will be described in more detail with reference to FIG. The jetting unit 250 can be divided into an upper plate 251 and a lower plate 252. In the upper plate, a precursor accommodating portion 260 capable of accommodating an organometallic precursor introduced from the outside is formed. In the precursor accommodating portion, an organometallic precursor inlet 202 for transferring the organometallic precursor into the precursor accommodating portion is formed The lower plate includes a plurality of second injection nozzles 261, one end of which is connected to the precursor accommodating portion and the other end of which is opened to the injection space so as to inject the organic metal precursor. And a plurality of first injection nozzles formed so as to penetrate through the ejection portion so that one end communicates with the plasma generation portion and the other end opens to the ejection space.

According to the present invention, the process gas is introduced through a process gas inlet, plasma-processed by a plasma generator to produce radicals, and the process gas containing the radicals is transferred through a first injection nozzle and seated on a substrate, The organometallic precursor may be introduced through the organometallic precursor inlet and transferred to the precursor receptacle and may be seated on the substrate through the second injection nozzle.

Generally, in order to perform a deposition process on a substrate, a single gas such as hydrogen, oxygen, H ₂ O, nitrogen, argon, helium, or the like or a mixed gas of two or more of the above gases may be used as a process gas for generating plasma Since the supply amount is preferably 50-500 sccm, it is preferable that the width of the injection nozzle is designed to be in the range capable of supplying the supply amount, and the deposition process may be repeatedly performed 1 to several times.

According to the present invention, the width of the first injection nozzle may be 1-10 mm, preferably 2-5 mm, and the width of the second injection nozzle may be 0.1-3 mm.

According to the present invention, in order to minimize the loss of the plasma in the deposition process for the substrate, and to supply a smooth process gas and a large amount of radicals onto the substrate, it is preferable to adjust the long-term ratio of the injection nozzle.

The first injection nozzle may have a value obtained by dividing a width by a length greater than 0.05. Preferably, the value obtained by dividing the width by the length may be larger than 0.1 and smaller than 0.5, and more preferably, the value obtained by dividing the width by the length is 0.2 And it may be smaller than 0.3. In the above range, plasma transfer efficiency is high, so that it is possible to supply a smooth process gas onto the substrate and to supply a large amount of radicals.

If the width of the first injection nozzle is out of the above range, the efficiency of transferring the radicals generated by the plasma treatment is increased, but the uniformity of mixing of the organic metal precursor and the reactive gas on the substrate is locally deteriorated, The uniformity of the composition of the thin film is lowered and the uniformity of the deposition rate is locally deteriorated, so that it is difficult to secure the desired thin film characteristics. When the width of the first injection nozzle is smaller than the above ratio, it is changed from the active species to the inactive species due to the collision with the wall surface or the vapor phase collision in the process of passing through the first injection nozzle, and the effect of plasma application is greatly reduced. Or the ratio of the active species passing through the nozzle is sharply reduced.

Generally, since the organic metal precursor is highly reactive, when it is mixed with a process gas in advance, a large number of particles are generated due to an excessive reaction before passing through the spray plate to cause a problem that the spray nozzle is clogged. However, The first injection nozzle can inject radicals generated by plasma processing of the process gas into the substrate, and the second injection nozzle includes an organometallic precursor The two gases are not mixed with each other until reaching the injection space, so that damage of the organic metal precursor due to contact with the radical can be prevented, and the metal thin film can be efficiently deposited.

The high frequency power may be 0 to 2000 Watt, and may be supplied for 10 seconds to 600 seconds, but is not limited thereto.

The temperature of the substrate that is seated on the susceptor may be 50-500 ° C,

The deposition can be performed in the range of 100-1000 mTorr.

The power supply unit includes an insulating member for applying power to generate a plasma in the plasma generating unit.

The thin film deposition apparatus having a showerhead according to the present invention can deposit a thin film with a thickness of 100 to 20,000 A / min.

According to the present invention, the thin film deposition apparatus may be a plasma induced chemical vapor deposition apparatus.

According to the present invention, the thin film deposition apparatus may be a plasma-induced atomic layer deposition apparatus.

Hereinafter, an embodiment in which a ZnO ₂ thin film is deposited using the thin film deposition apparatus constructed as described above will be described.

A process gas is supplied to the process gas inlet 201, a precursor is supplied to the organometallic gas inlet 202, and a power source of the high voltage electrode is applied to generate a plasma.

Example

The substrate (borosilicate glass; 20 X 20 mm ² ) was diluted with isopropylalcohol (IPA) for 10 minutes and Standard Cleaning 1 (SC1) for 10 minutes, diluted hydrofluoride DHF) for 5 minutes, followed by drying with nitrogen and washing.

A showerhead having a spraying portion having a width (a) of the first spraying nozzle divided by a length (c) of 0.25, a width of the first spraying nozzle of 3 mm and a width of the second spraying nozzle of 1 mm was mounted, .

The substrate was placed on a susceptor, purged with argon, treated with H ₂ O plasma conditions, purged again with argon, AZO (Aluminum Zinc Oxide) was deposited, and then purged with argon to complete ZnO deposition Respectively.

In order to confirm the effect of the plasma propagation through the deposition experiment according to the RF power under the above process conditions, the results are shown in FIG. 12 and FIG. 13. The substrate temperature was set at 150 ° C and DEZn and H2O were supplied to the reactor at 10 sccm and 40 sccm respectively. The pressure was set to 300 mTorr and the deposition time was 180 seconds. Referring to FIG. 12, when the plasma is not applied, the film thickness is about 550 nm when the RF power is applied for 180 seconds. However, when RF power of 200 W is applied, the film thickness is increased to about 700 nm to about 30% And the deposition rate is improved in accordance with the RF power in the range therebetween. Therefore, it can be seen that the radical transfer efficiency of the shower head used in this embodiment is very excellent. FIG. 13 is a graph showing the electrical characteristics of the deposited thin film. When the plasma is not applied, the resistivity is very high because the reaction between the organometallic precursor and the H 2 O proceeds incompletely at a low deposition temperature and the impurity concentration in the thin film is high And the crystallinity is low. As the plasma power is increased, the resistivity is greatly improved. As a result, it can be seen that the radical generated in the plasma reacts with the organometallic precursor to form a very good thin film. This shows that XRD and ultraviolet- Visible light transmission experiments were also confirmed. From these results, it can be seen that when the reaction gas is excited by the remote plasma and then the shower head can effectively transmit the plasma, high productivity and excellent thin film characteristics can be obtained even at a low temperature.

14 is a graph showing a deposition rate of a ZnO thin film according to a substrate temperature under a condition that a plasma power is 150 watt. The plasma effect and the substrate effect showed a synergistic effect. The ZnO thin film exhibited a rapid deposition rate of more than 1000 nm per minute at a deposition temperature of about 250 ° C. This was because the deposition rate per minute (100 to 300 nm) It can be seen that the productivity can be greatly improved by about 2 to 3 times faster. However, in many plasma enhanced metal-organic chemical vapor deposition, the excellent results shown in this example are often not obtained, which is considered to be due to the low plasma transfer efficiency. Therefore, if the technology of this patent is utilized, it is considered that it can contribute to improvement of the characteristics of the thin film and increase of the productivity.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation in the embodiment in which said invention is directed. It will be understood by those skilled in the art that various changes may be made and equivalents may be resorted to without departing from the scope of the appended claims.

100 chamber
201 Process gas inlet 202 Organometallic precursor inlet
210 gas diffusion plates 220, 221 and 222,
230, 231, 232 High frequency electrode 240 Fixing unit
250 minutes 251 upper plate
252 Lower plate 260 Precursor receiving part
261 Second injection nozzle 270 First injection nozzle
280 injection space
300 susceptor

Claims

A plasma generator;
A process gas inlet connected to the upper side of the plasma generator; And
And a jetting section located below the plasma generating section,
A plurality of first injection nozzles formed to penetrate through the injection unit so that one end thereof communicates with the plasma generation unit and the other end opens into the injection space so as to inject the radicals generated in the plasma generation unit into the injection space;
A precursor accommodating portion formed in the injection portion and containing an organometallic precursor supplied from the outside;
And a plurality of second injection nozzles, one end of which is connected to the precursor accommodating portion and the other end of which is opened to the injection space so as to inject the organometallic precursor contained in the precursor accommodating portion into the injection space. .

The method according to claim 1,
Further comprising a gas diffusion plate between the plasma generating unit and the process gas inlet.

3. The method of claim 2,
Wherein the gas diffusion plate is of a plate shape in which a plurality of holes are densely formed.

The method according to claim 1,
Wherein the first injection nozzle has a value obtained by dividing a width by a length of greater than 0.05.

The method according to claim 1,
Wherein the first injection nozzle has a value obtained by dividing a width by a length greater than 0.1 and smaller than 0.5.

The method according to claim 1,
Wherein the first injection nozzle has a width divided by a length of more than 0.2 and less than 0.3.

The method according to claim 1,
Wherein the width of the first injection nozzle is 1-10 mm.

The method according to claim 1,
And the width of the second injection nozzle is 0.1 to 3 mm.

The method according to claim 1,
Wherein an electrode to which high-frequency power is supplied is provided in the plasma generating portion.

The method according to claim 1,
Wherein the radical is generated by converting the process gas introduced through the inlet into plasma by the plasma generator.

The method according to claim 1,
Wherein the first injection nozzle and the second injection nozzle are made of one or more materials selected from the group consisting of stainless steel, nickel, aluminum alloy and aluminum oxide.

The method according to claim 1,
Wherein the precursor receiving portion further comprises an organometallic gas inlet.

A chamber in which a space is formed in which a deposition process for the substrate is performed;
A susceptor installed inside the chamber and on which the substrate is placed; And
A thin film deposition apparatus, comprising: the showerhead according to any one of claims 1 to 12.

14. The method of claim 13,
Wherein the thin film deposition apparatus is a plasma chemical vapor deposition apparatus.

14. The method of claim 13,
Wherein the thin film deposition apparatus is a plasma atomic layer deposition apparatus,