KR20080061811A - Surface processing apparatus for substrate - Google Patents

Surface processing apparatus for substrate Download PDF

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Publication number
KR20080061811A
KR20080061811A KR1020060136935A KR20060136935A KR20080061811A KR 20080061811 A KR20080061811 A KR 20080061811A KR 1020060136935 A KR1020060136935 A KR 1020060136935A KR 20060136935 A KR20060136935 A KR 20060136935A KR 20080061811 A KR20080061811 A KR 20080061811A
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KR
South Korea
Prior art keywords
inner antenna
plasma
height
reaction gas
surface treatment
Prior art date
Application number
KR1020060136935A
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Korean (ko)
Inventor
성명은
Original Assignee
주식회사 케이씨텍
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Publication date
Application filed by 주식회사 케이씨텍 filed Critical 주식회사 케이씨텍
Priority to KR1020060136935A priority Critical patent/KR20080061811A/en
Publication of KR20080061811A publication Critical patent/KR20080061811A/en

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    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
    • C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
    • C23C16/455—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating characterised by the method used for introducing gases into reaction chamber or for modifying gas flows in reaction chamber
    • C23C16/45563—Gas nozzles
    • C23C16/45565—Shower nozzles
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
    • C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
    • C23C16/50—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating using electric discharges
    • C23C16/505—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating using electric discharges using radio frequency discharges
    • C23C16/509—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating using electric discharges using radio frequency discharges using internal electrodes
    • C23C16/5096—Flat-bed apparatus
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
    • C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
    • C23C16/50—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating using electric discharges
    • C23C16/513—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating using electric discharges using plasma jets
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/67—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere
    • H01L21/67005—Apparatus not specifically provided for elsewhere
    • H01L21/67242—Apparatus for monitoring, sorting or marking

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Materials Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Plasma & Fusion (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Manufacturing & Machinery (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Plasma Technology (AREA)
  • Drying Of Semiconductors (AREA)

Abstract

An apparatus processing a surface of a substrate is provided to uniformly distribute a reaction gas and a source gas by uniformly distributing a reaction gas plasma in a plasma generating space. An inner antenna(180) is installed in a plasma generating space(150), and is connected to a radio frequency power supplier(160). A height adjusting unit(195) adjusts a height of the inner antenna according to plasma density in the plasma generating space. A pressure sensor is additionally installed in the plasma generating space, and the height adjusting unit adjusts the height of the inner antenna according to the pressure detected by the pressure sensor. The height adjusting unit moves the inner antenna up if the pressure is lower than a reference value, and moves the inner antenna down if the pressure is higher than the reference value.

Description

Substrate surface treatment equipment {SURFACE PROCESSING APPARATUS FOR SUBSTRATE}

1 and 2 is a view showing a conventional substrate surface treatment apparatus,

3 is a view showing a substrate surface treatment apparatus according to a preferred embodiment of the present invention.

<Description of Major Symbols in Drawing>

115: processing space 120: substrate or wafer

130: heater 140: first shower head

141: top of the shower head 142: bottom of the shower head

150: plasma generation space 160: RF power supply

170: exhaust port 180: inner antenna

181: electrode 182: dielectric

190: second shower head 195: height adjustment unit

197: cooling unit 198: cooling water circulation structure

The present invention relates to a substrate surface treatment apparatus, and more particularly, to a substrate surface treatment apparatus capable of improving the surface treatment performance of a substrate by allowing the reaction gas plasma to be uniformly distributed.

In unit processes, such as dry etching, physical or chemical vapor deposition, photoresist cleaning, and other surface treatment, the method using plasma is widely used.

Examples of conventional substrate surface treatment apparatuses include those introduced in Korean Patent Application Nos. 1997-33864 and 2001-24902. For the generation of plasma, an ICP antenna may be used as an electrode, or a flat plate may be used as an electrode, such as CCP. .

1 is a view showing a thin film deposition apparatus 100 using a general plasma.

As shown in FIG. 1, the thin film deposition apparatus 100 using plasma is a method for depositing a high quality thin film at a low temperature, and is sourced through a showering method using a plurality of holes formed at a lower portion during plasma spraying. The reaction between the gas and the reaction gas is more activated.

Here, the thin film deposition apparatus 100 has a chamber (110) is formed in the lower exhaust port 170 to maintain the internal environment in a vacuum state, and formed in the upper portion of the chamber to form a plurality of injection holes in the lower Shower head 140 for injecting the source gas and the reaction gas supplied from the source gas supply unit and the reaction gas supply unit, and a wafer or substrate on which the source gas ions activated by the reaction gas injected by the shower head is deposited in a thin film ( Hereinafter, the heater 130 is provided to support the substrate 120 and provide a predetermined heat source.

In addition, the thin film deposition apparatus 100 forms a gas supply port (not shown) through which the source gas and the reaction gas are supplied from the source gas supply unit and the reaction gas supply unit.

In addition, the thin film deposition apparatus 100 is connected to the RF power supply unit 160 for the plasma generation of the supplied reaction gas plasma.

In the thin film deposition apparatus 100 configured as described above, the thin film deposition process on the substrate 120 is as follows.

That is, when the heater 130 supplies the thermal energy to heat the substrate 120 to be deposited and the high frequency power is applied to the plasma generating unit formed thereon, the reaction gas is plasma-reacted. At this time, the reaction gas in the plasma state to activate the source gas is source gas injected from the shower head is deposited on the substrate 120 as a thin film.

2 illustrates a conventional substrate surface treatment apparatus in more detail. The plasma generating unit, which is positioned at the upper side and reacts with a plasma, is formed of an ICP type. The plasma generation unit may include an ICP type antenna connected to the first RF power supply unit 160 to which RF power is applied, and a plasma generation space 150 for converting the reaction gas introduced by the ICP method into a plasma ion state. Equipped.

In FIG. 2, the reaction gas is supplied to the plasma generating space 150 to be plasma-reacted and injected into the processing space 115 in which the substrate 120 is located through a plurality of induction tubes formed in the shower head 140.

The shower head 140 includes an upper plate 141 having a plurality of induction tubes and a lower plate 142 having a plurality of source gas holes formed separately from the through holes through which the induction tubes penetrate.

A buffer space is formed between the upper plate 141 and the lower plate 142 to accommodate the source gas, and the source gas is supplied from the external source gas supply unit 145 to the buffer space. The source gas supplied to the buffer space is injected into the lower processing space 115 through the source gas hole. Reference numeral 144 denotes a reaction gas supply unit.

In the conventional inductively coupled plasma generator, that is, the ICP type plasma generator, a single spiral antenna or a plurality of split-electrode antennas are used. A magnetic field is formed, and this temporally changing magnetic field forms an induction electric field inside the plasma generating space, and the induction electric field heats electrons to generate a plasma inductively coupled with the antenna. The electrons collide with the surrounding neutral gas particles to generate ions and radicals, which are used for plasma etching and deposition.

However, in the antenna of the spiral structure, each winding constituting the antenna is connected in series, so the amount of current flowing in each winding becomes constant. In this case, it is difficult to control the distribution of the induced electric field. It is difficult to prevent the density of the plasma from decreasing in the central part of the high density near the inner wall. Therefore, it is extremely difficult to keep the density of the plasma uniform. In addition, since each winding of the antenna is connected in series, the voltage drop caused by the antenna is increased, thereby increasing the influence of capacitive coupling with the plasma. Therefore, the power efficiency is lowered and it is also difficult to maintain the uniformity of the plasma.

Next, in the antenna having three split-pole structures connected to three high frequency power sources having different phases from each other, the plasma density is high at the position close to each split electrode, and the plasma density is lower at the center of the chamber. Difficulty in securing, and in particular, processing a large area of sample is significantly difficult. In addition, since power must be used independently of each other, the cost increases, and there is a problem in that an independent impedance matching circuit must be used for each divided electrode for impedance matching for efficient use of the power source.

In order to improve the uniformity of the plasma may be used to modify the antenna in the form of a dome, but it has a limitation that it is difficult to apply to the process such as oxide etching and the complicated structure.

The present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to provide a substrate surface treatment apparatus for securing the uniformity of the density of the reaction gas plasma in the plasma generating space.

Therefore, the density of the reaction gas and the source gas injected into the processing space in which the object to be processed is uniform may improve surface treatment performance.

The substrate surface treatment apparatus according to the present invention comprises: an inner antenna connected to a high frequency power supply unit and installed to be elevated in a plasma generation space; And a height adjusting unit for adjusting the height of the inner antenna according to the plasma density in the plasma generating space.

Preferably, a pressure sensor is provided in the plasma generating space, and the height adjusting unit adjusts the height of the inner antenna according to the pressure sensed by the pressure sensor.

The height adjusting unit may be configured to raise the inner antenna to the top when the pressure is lower than the reference value, and to lower to the bottom when the pressure is higher than the reference value.

The inner antenna is preferably formed in a flat plate shape. An electrode is embedded in a dielectric, and the high frequency power supply unit is connected to the electrode.

More preferably, a cooling unit for cooling the inner antenna is further provided.

In addition, the reaction gas shower head for dispersing the reaction gas widely in the plasma generating space is preferably further provided. The reaction gas shower head may be provided above the plasma generation space or be provided below the inner antenna.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, and in the following description with reference to the accompanying drawings, the same or corresponding components are denoted by the same reference numerals, regardless of the reference numerals. Duplicate explanations will be omitted.

3 is a view showing a substrate surface treatment apparatus 200 according to a preferred embodiment of the present invention.

As shown in FIG. 3, the inner antenna 180 is located in the plasma generation space 150. The inner antenna 180 has a form of a disc in which an electrode 181 connected to the RF power supply 160 is embedded in the dielectric 182.

The inner antenna 180 is provided to be height-adjustable by the height adjusting unit 195. In addition, the means for height adjustment may utilize a height adjustment means that is well known in the art. For example, the height of the inner antenna 180 may be adjusted by hydraulic, mechanical, or electronic.

The height adjusting unit 195 adjusts the height of the inner antenna 180 according to the plasma density in the plasma generating space 150. Here, although the plasmid density is taken as an example, the height of the inner antenna 180 may be adjusted according to the power of the RF power, the type of gas supplied, the amount of gas, the pressure, and the like.

For example, the height adjustment of the inner antenna 180 according to the pressure will be described by way of example.

A pressure sensor (not shown) is provided in the plasma generating space 150, and a signal of the pressure sensor is transmitted to the height adjusting unit 195. The height adjusting unit 195 adjusts the height of the inner antenna 180 according to the signal of the pressure sensor.

Preferably, the height adjusting unit 195 raises the inner antenna 180 when the pressure sensed by the pressure sensor is lower than the reference value, and lowers the inner antenna 180 when the pressure is higher than the reference value. Get off. Here, the reference value is programmed and stored in a memory or the like and can be updated as a setting value. In addition, the pressure sensor as described above may be provided in plurality.

Since the inner antenna 180 is height-adjusted according to the pressure, it is possible to secure a uniform distribution of the reaction gas plasma.

In addition, a second shower head 190 is provided on the inner antenna 180 separately from the first shower head 140 installed below. The reaction gas introduced from the reaction gas supply unit 144 to the upper portion of the plasma generation space 150 is sprayed widely through the second shower head 190 and uniformly distributed.

Although not shown, the inner antenna 180 may be provided with a plurality of injection holes. Thus, the inner antenna 180 itself having the plurality of injection holes may take the role of the second shower head 190. That is, the second shower head 190 may be formed to be integrated with the inner antenna 180.

In addition, even if not integrated form, when a plurality of injection holes are provided in the inner antenna 180, it can be free from the arrangement of the second shower head 190. For example, the reaction gas injected through the upper second showerhead 190 may be introduced while maintaining uniformity under the inner antenna 180. In addition, the second shower head 190 may be provided under the inner antenna 180.

The reaction gas is uniformly distributed in the plasma generating space 150 and plasma-reacted, and then injected into the processing space 115 through the first shower head 140 positioned below.

The source gas is supplied to the buffer space provided in the first shower head 140 and injected into the processing space 115 through the injection hole.

As such, since the shower head is provided in two, the reaction gas is widely sprayed in the plasma generating space 150 by the second shower head 190, and thus may be uniformly distributed. In addition, the uniformly distributed reaction gas is injected into the processing space 115 through the first shower head 140 together with the source gas. Therefore, the uniformity of reaction gas and source gas distribution can be ensured further.

Meanwhile, a cooling unit 197 is provided to cool the inner antenna 180, and the cooling unit 197 may be implemented in various forms such as cooling through air or cooling through cooling water. For example, in the cooling method through the cooling water, the inner antenna 180 is cooled by supplying the cooling water to the inner antenna 180 and circulating the same. At this time, the inner antenna 180 is provided with a circulation structure 198 through which the cooling water can be circulated.

The substrate surface treatment apparatus according to the present invention is not limited to the thin film deposition apparatus, and various types of semiconductors and FPDs used in unit processes such as dry etching using plasma, physical or chemical vapor deposition, photoresist cleaning, and other surface treatments. Applicable to surface treatment equipment.

Therefore, the present invention is not limited to the above-described embodiments, and a person having ordinary skill in the art may change the design or avoid the design without departing from the scope of the technical idea of the present invention. Will be in range.

As described above, according to the present invention, the reaction gas plasma may be uniformly distributed in the plasma generating space and injected into the processing space. In addition, since the source gas is uniformly injected into the processing space through the shower head, the reaction gas and the source gas are uniformly distributed.

As such, since the density of the reaction gas and the source gas injected into the processing space where the object is located is uniformly distributed, the surface treatment performance is improved.

Claims (6)

An inner antenna connected to the high frequency power supply unit and installed to be liftable in the plasma generation space; A height adjusting unit adjusting the height of the inner antenna according to the plasma density in the plasma generating space; Substrate surface treatment apparatus comprising a. The method of claim 1, A pressure sensor is further provided in the plasma generating space, and the height adjusting unit controls the height of the inner antenna according to the pressure sensed by the pressure sensor. The method of claim 2, And the height adjusting part raises the inner antenna upward when the pressure is lower than the reference value, and lowers the inner antenna upward when the pressure is higher than the reference value. The method of claim 1, The inner antenna is a substrate surface treatment apparatus, characterized in that the electrode is embedded in the form of a plate-like dielectric. The method of claim 1, Substrate surface treatment apparatus further comprises a cooling unit for cooling the inner antenna. The method of claim 1, Substrate surface treatment apparatus further comprises a shower head for injecting a wide reaction gas in the plasma generating space.
KR1020060136935A 2006-12-28 2006-12-28 Surface processing apparatus for substrate KR20080061811A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR1020060136935A KR20080061811A (en) 2006-12-28 2006-12-28 Surface processing apparatus for substrate

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Application Number Priority Date Filing Date Title
KR1020060136935A KR20080061811A (en) 2006-12-28 2006-12-28 Surface processing apparatus for substrate

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101050463B1 (en) * 2009-05-07 2011-07-20 삼성모바일디스플레이주식회사 Plasma processing equipment
KR20140108178A (en) * 2013-02-28 2014-09-05 노벨러스 시스템즈, 인코포레이티드 Ceramic showerhead with embedded rf electrode for capacitively coupled plasma reactor

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101050463B1 (en) * 2009-05-07 2011-07-20 삼성모바일디스플레이주식회사 Plasma processing equipment
US8901008B2 (en) 2009-05-07 2014-12-02 Samsung Display Co., Ltd. Substrate plasma-processing apparatus
KR20140108178A (en) * 2013-02-28 2014-09-05 노벨러스 시스템즈, 인코포레이티드 Ceramic showerhead with embedded rf electrode for capacitively coupled plasma reactor
KR20210023915A (en) * 2013-02-28 2021-03-04 노벨러스 시스템즈, 인코포레이티드 Ceramic showerhead with embedded rf electrode for capacitively coupled plasma reactor
KR20220084000A (en) * 2013-02-28 2022-06-21 노벨러스 시스템즈, 인코포레이티드 Ceramic showerhead with embedded rf electrode for capacitively coupled plasma reactor

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