WO2015174517A1 - ｐ型酸化亜鉛膜の製造方法 - Google Patents

ｐ型酸化亜鉛膜の製造方法 Download PDF

Info

Publication number
WO2015174517A1
WO2015174517A1 PCT/JP2015/064018 JP2015064018W WO2015174517A1 WO 2015174517 A1 WO2015174517 A1 WO 2015174517A1 JP 2015064018 W JP2015064018 W JP 2015064018W WO 2015174517 A1 WO2015174517 A1 WO 2015174517A1
Authority
WO
WIPO (PCT)
Prior art keywords
film
zinc oxide
oxide film
target
source
Prior art date
Application number
PCT/JP2015/064018
Other languages
English (en)
French (fr)
Inventor
種村　眞幸
守道 渡邊
吉川　潤
七瀧　努
Original Assignee
国立大学法人名古屋工業大学
日本碍子株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 国立大学法人名古屋工業大学, 日本碍子株式会社 filed Critical 国立大学法人名古屋工業大学
Priority to JP2016519311A priority Critical patent/JP6609764B2/ja
Publication of WO2015174517A1 publication Critical patent/WO2015174517A1/ja
Priority to US15/346,831 priority patent/US9934968B2/en

Links

Images

Classifications

    • 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
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104—Forming layers
    • H01L21/02365—Forming inorganic semiconducting materials on a substrate
    • H01L21/02518—Deposited layers
    • H01L21/02521—Materials
    • H01L21/02551—Group 12/16 materials
    • H01L21/02554—Oxides
    • 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
    • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
    • C23C14/0021—Reactive sputtering or evaporation
    • 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
    • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
    • C23C14/06—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the coating material
    • C23C14/08—Oxides
    • C23C14/086—Oxides of zinc, germanium, cadmium, indium, tin, thallium or bismuth
    • 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
    • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
    • C23C14/22—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the process of coating
    • 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
    • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
    • C23C14/22—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the process of coating
    • C23C14/24—Vacuum evaporation
    • C23C14/32—Vacuum evaporation by explosion; by evaporation and subsequent ionisation of the vapours, e.g. ion-plating
    • C23C14/325—Electric arc evaporation
    • 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
    • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
    • C23C14/58—After-treatment
    • C23C14/5806—Thermal treatment
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
    • H01J37/32—Gas-filled discharge tubes
    • H01J37/32009—Arrangements for generation of plasma specially adapted for examination or treatment of objects, e.g. plasma sources
    • H01J37/32055—Arc discharge
    • 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
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104—Forming layers
    • H01L21/02365—Forming inorganic semiconducting materials on a substrate
    • H01L21/02367—Substrates
    • H01L21/0237—Materials
    • H01L21/0242—Crystalline insulating materials
    • 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
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104—Forming layers
    • H01L21/02365—Forming inorganic semiconducting materials on a substrate
    • H01L21/02367—Substrates
    • H01L21/02433—Crystal orientation
    • 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
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104—Forming layers
    • H01L21/02365—Forming inorganic semiconducting materials on a substrate
    • H01L21/02518—Deposited layers
    • H01L21/0257—Doping during depositing
    • H01L21/02573—Conductivity type
    • H01L21/02579—P-type
    • 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
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104—Forming layers
    • H01L21/02365—Forming inorganic semiconducting materials on a substrate
    • H01L21/02612—Formation types
    • H01L21/02614—Transformation of metal, e.g. oxidation, nitridation
    • 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
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104—Forming layers
    • H01L21/02365—Forming inorganic semiconducting materials on a substrate
    • H01L21/02612—Formation types
    • H01L21/02617—Deposition types
    • H01L21/02631—Physical deposition at reduced pressure, e.g. MBE, sputtering, evaporation
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2237/00—Discharge tubes exposing object to beam, e.g. for analysis treatment, etching, imaging
    • H01J2237/32—Processing objects by plasma generation
    • H01J2237/33—Processing objects by plasma generation characterised by the type of processing
    • H01J2237/332—Coating

Definitions

  • the present invention relates to a method for producing a p-type zinc oxide film using arc plasma.
  • Zinc oxide (ZnO) has a very high potential as a safe and inexpensive semiconductor material, but is known to be difficult to synthesize p-type zinc oxide.
  • film forming methods such as molecular beam epitaxy (MBE) and pulsed laser deposition (PLD) have been proposed so far, but it is difficult to form a film on a large area. there were.
  • Patent Document 1 Japanese Patent No. 4072620 discloses a p-type oxide doped with nitrogen by evaporating zinc using an arc discharge in an oxygen-nitrogen mixed gas atmosphere having a gas pressure of 20 ⁇ 10 3 Pa, for example.
  • Patent Document 2 Japanese Patent Application Laid-Open No. 2008-244387 discloses a light-emitting element using nitrogen-doped p-type zinc oxide crystal particles.
  • the p-type zinc oxide crystal particles are also 20 ⁇ , for example. It is manufactured by evaporating zinc using arc discharge in an oxygen-nitrogen mixed gas atmosphere having a gas pressure of 10 3 Pa.
  • the p-type zinc oxide disclosed in Patent Documents 1 and 2 is in powder form.
  • p-type zinc oxide in powder form there is a problem that only a semiconductor device with low efficiency can be produced. Therefore, in order to produce a semiconductor device with higher efficiency, a method capable of producing p-type zinc oxide in a film form is desired.
  • the present inventors have now formed a film using an arc discharge in a gas atmosphere containing a nitrogen source and an oxygen source at a gas pressure of 0.1 to 100 Pa, and the resulting film is formed in an oxidizing atmosphere. It has been found that by annealing, a p-type zinc oxide film that has been considered difficult to synthesize can be stably formed.
  • An object of the present invention is to provide a manufacturing method that can stably form a p-type zinc oxide film and that is suitable for a large area.
  • a method for manufacturing a p-type zinc oxide film A target including a zinc source and a deposition target substrate are placed in a gas atmosphere including a nitrogen source and an oxygen source at a gas pressure of 0.1 to 100 Pa, and the target is exposed to arc discharge so that zinc is deposited on the deposition target substrate. And forming a precursor film containing oxygen, Annealing the precursor film in an oxidizing atmosphere to obtain a p-type zinc oxide film;
  • Example 2 is an SCM image (p / n polarity image) of the film produced in Example 1.
  • the present invention is a method for producing a p-type zinc oxide film.
  • the term “film” means that a constituent component (that is, zinc oxide) is bonded in a planar shape to the surface of a solid such as a substrate, or a constituent particle on the surface of a solid such as a substrate. (That is, zinc oxide particles) are connected to each other in the shape of a plane and the shape is maintained. In that sense, a powder deposit that is simply deposited in layers on the substrate without the constituent particles being connected to each other is not a “film”.
  • Whether or not it is such a “film” is determined, for example, by immersing the film-formed substrate in a solvent in which the film component such as ethanol and the substrate are insoluble and non-reactive and drying, and then before and after immersion and drying. It can be determined by whether it remains as a film-like residue without change.
  • a target including a zinc source and a deposition target substrate are set with a nitrogen source and an oxygen source having a gas pressure of 0.1 to 100 Pa. Install in a gas atmosphere. Subsequently, the target including the zinc source is exposed to arc discharge to generate vapor including ions including the zinc source, neutral species, and the like, thereby forming a precursor film including zinc and oxygen on the deposition target substrate. Next, this precursor film is annealed in an oxidizing atmosphere to obtain a p-type zinc oxide film.
  • a method of forming a film by exposing the target to arc discharge is generally known, and an arc discharge film forming apparatus is also commercially available.
  • the present inventors have reported that a p-type zinc oxide film has been obtained. As far as I know, it has never been done.
  • both of the p-type zinc oxide crystals reported in Patent Documents 1 and 2 are in powder form, not in film form.
  • a gas containing a nitrogen source and an oxygen source having a gas pressure of 0.1 to 100 Pa (much lower than the gas pressure of 20 ⁇ 10 3 Pa employed in Patent Documents 1 and 2).
  • a p-type zinc oxide film can be formed in a larger area compared to conventional methods such as molecular beam epitaxy (MBE) method and pulsed laser deposition (PLD) method.
  • MBE molecular beam epitaxy
  • PLD pulsed laser deposition
  • a target containing a zinc source and a substrate to be deposited are placed in a gas atmosphere containing a nitrogen source and an oxygen source at a gas pressure of 0.1 to 100 Pa. Then, the target is exposed to arc discharge to form a film made of a precursor containing zinc and oxygen, which may be zinc oxide, on the deposition target substrate.
  • the composition of the precursor film may be zinc oxide equivalent to or close to the stoichiometric composition of ZnO, or may be a zinc oxide-like composition lacking oxygen. This is because even a composition lacking oxygen can be supplemented with oxygen in the subsequent annealing step.
  • the arc discharge may be generated by causing it to occur by using known conditions and apparatuses, and vapor including ions including a zinc source, neutral species, and the like can be generated from the target by the arc discharge. And the vapor
  • the arc discharge is preferably formed in a vacuum chamber, and after evacuating the vacuum chamber to a desired degree of vacuum (eg, 1 ⁇ 10 ⁇ 8 to 100 Pa, preferably 1 ⁇ 10 ⁇ 8 to 0.1 Pa).
  • a gas atmosphere containing a nitrogen source and an oxygen source may be introduced. Accordingly, a pressure of 0.1 to 100 Pa in a gas atmosphere containing a nitrogen source and an oxygen source is approximately the total pressure of the vacuum chamber during film formation.
  • the formation of the precursor film using arc discharge is particularly preferably performed using an arc plasma gun.
  • arc plasma gun vapor containing zinc source generated through arc discharge can be emitted with directivity according to the direction of the injection port, so high quality precursor film can be formed at high deposition rate. It is also suitable for increasing the area.
  • it is preferable to perform film formation by attaching an arc plasma gun loaded with a target to a vacuum apparatus and extending an injection port of the arc plasma gun into a vacuum chamber of the vacuum apparatus.
  • the atmospheric gas is a gas containing a nitrogen source and an oxygen source, and may be a multi-component gas (that is, a mixed gas) as long as it contains nitrogen atoms and oxygen atoms in any form, or a one-component system.
  • Gas for example, nitrogen oxide gas
  • a preferable atmospheric gas is a mixed gas of N 2 and O 2 , and may be air, for example.
  • the mixed gas of N 2 and O 2 preferably has a N 2 / O 2 ratio of 99/1 to 10/90 on a molar basis, more preferably 90/10 to 50/50.
  • the pressure of the atmospheric gas is 0.1 to 100 Pa. Such a gas pressure is much lower than the gas pressure of 20 ⁇ 10 3 Pa exemplified in Patent Documents 1 and 2, which contributes to the formation of a high-quality film (not just a powdery layer adhesion). It is thought that it is doing.
  • the target including the zinc source is a source of zinc atoms that can form the zinc oxide film, and may be any target that includes zinc atoms in a form that evaporates when exposed to arc discharge.
  • the target containing a zinc source include a metal zinc target, a zinc alloy target, and a conductive zinc oxide target.
  • the precursor film tends to have a zinc oxide-like composition lacking oxygen, but this is presumed to obtain p-type characteristics by supplementing oxygen in the subsequent annealing step. (This is only a guess and the present invention should not be limited to this).
  • the substrate on which the precursor film is to be formed is not particularly limited as long as the material does not interfere with the quality (for example, crystallinity and p-type characteristics) of the p-type zinc oxide film.
  • preferred substrates include sapphire substrates.
  • the sapphire substrate may have any surface orientation such as a-plane, c-plane, m-plane, and r-plane.
  • preferred examples of the substrate include a zinc oxide single crystal and an oriented polycrystalline zinc oxide sintered body.
  • a p-type zinc oxide film may be formed on an n-type zinc oxide film on the substrate.
  • membrane which can become a light emitting layer on the said n-type zinc oxide film
  • the obtained precursor film is annealed (heat treatment) in an oxidizing atmosphere to obtain a p-type zinc oxide film.
  • the precursor film is modified to a p-type zinc oxide film. Therefore, the annealing may be performed under conditions that provide a p-type zinc oxide film, and the temperature and time thereof are not particularly limited. It may be performed for 1 minute to 5 hours.
  • the oxidizing atmosphere may be an atmosphere containing any oxidizing gas, but is preferably an air atmosphere or an O 2 atmosphere.
  • the film finally obtained in this way is a p-type zinc oxide film.
  • Whether or not the obtained zinc oxide film is p-type can be determined by acquiring an SCM image (p / n polarity image) using a commercially available scanning capacitance microscope (SCM).
  • SCM scanning capacitance microscope
  • thermoelectromotive force measuring device it can be determined whether it is p-type, and if a p-type signal is obtained in the majority of the measurement locations, it can be determined as p-type. If a p-type signal is obtained at 3 out of 5 measurement locations, it may be determined as p-type.
  • it is possible to determine whether or not the zinc oxide film is p-type by using another method such as Hall effect measurement.
  • the thickness of the p-type zinc oxide film is not particularly limited as long as it is appropriately determined depending on the application, but it can be preferably 1 nm or more.
  • Example 1 A p-type zinc oxide film was produced on an a-plane sapphire substrate using an arc plasma gun (ULVAC, Hyper Arc Plasma Gun ARL-300) (hereinafter referred to as APG) as follows.
  • UVAC Ultra Arc Plasma Gun ARL-300
  • APG Hyper Arc Plasma Gun
  • an a-plane sapphire having a size of 10 mm ⁇ 10 mm was prepared as a substrate, and metallic zinc (purity> 99%) was prepared as a target for APG.
  • the APG loaded with the metal zinc target and the substrate were attached to a vacuum apparatus. After operating the vacuum device to evacuate the vacuum chamber to a vacuum degree of about 1 ⁇ 10 ⁇ 4 Pa, the atmosphere is introduced to 10 Pa, voltage: 100 V, capacitor unit: 1080 ⁇ F, substrate-anode electrode interval: 150 mm
  • the film number was formed by operating the APG under the condition of the number of pulses: 25000 pulses. The thickness of the obtained film was about 200 nm, and the film formation rate was 8 nm / 1000 pulses.
  • the thickness of the film was prepared by separately preparing a sample that had been partially masked under the same conditions, and the surface profile of this sample was measured using a small shape roughness measuring machine (Taylor-Hubson, Form Talysurf plus). It was performed by using and measuring.
  • the sapphire substrate thus formed was annealed at 400 ° C. for 3.5 hours in an air atmosphere.
  • the obtained film was subjected to a qualitative analysis of the film using an enclosed tube X-ray diffractometer (D8 ADVANCE, manufactured by Bruker AXS), and was confirmed to be zinc oxide. Moreover, when the film was evaluated using a scanning capacitance microscope (SCM) (Bruker Ax, NanoScope IV), the SCM image shown in FIG. 1 was obtained. From the SCM image shown in FIG. 1, a p-type dC / dV signal was detected from substantially the entire surface of the film, and it was confirmed that a p-type film was formed. Further, when a pn determination of the film was performed using a thermoelectromotive force measuring device (Napson's thermoelectromotive force measuring device PN-12 ⁇ ), p-type signals were obtained at 3 out of 5 measurement points.
  • SCM scanning capacitance microscope
  • the pn determination of the film was performed using the SCM and the thermoelectromotive force measuring device, but there is no problem even if evaluation is performed using another method such as Hall effect measurement.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Materials Engineering (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • Power Engineering (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Computer Hardware Design (AREA)
  • Manufacturing & Machinery (AREA)
  • General Physics & Mathematics (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Organic Chemistry (AREA)
  • Metallurgy (AREA)
  • Mechanical Engineering (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Analytical Chemistry (AREA)
  • Plasma & Fusion (AREA)
  • Thermal Sciences (AREA)
  • Physical Vapour Deposition (AREA)
  • Physical Deposition Of Substances That Are Components Of Semiconductor Devices (AREA)

Abstract

　ｐ型酸化亜鉛膜を安定的に形成可能な、大面積化にも適した製造方法が提供される。本発明によるｐ型酸化亜鉛膜の製造方法は、亜鉛源を含むターゲットと被成膜基板をガス圧０．１～１００Ｐａの窒素源及び酸素源を含むガス雰囲気中に設置し、ターゲットをアーク放電に曝して、前記被成膜基板上に亜鉛及び酸素を含む前駆体膜を形成する工程と、前駆体膜を酸化性雰囲気中でアニールしてｐ型酸化亜鉛膜を得る工程とを含んでなる。

Description

ｐ型酸化亜鉛膜の製造方法
　本発明は、アークプラズマを用いたｐ型酸化亜鉛膜の製造方法に関する。
　酸化亜鉛（ＺｎＯ）は安全かつ安価な半導体材料として非常に高い将来性を有しているが、ｐ型酸化亜鉛の合成が難しいことが知られている。ｐ型酸化亜鉛の製法として、これまでに分子線エピタキシー（ＭＢＥ）法、パルスレーザー堆積（ＰＬＤ）法等による成膜方法が提案されているが、大面積への成膜が難しいとの問題があった。
　一方、アーク放電を利用したｐ型酸化亜鉛粉末の合成法やそれを用いた発光素子の製法が知られている。例えば、特許文献１（特許第４０７２６２０号公報）には、例えば２０×１０３Ｐａといったガス圧の酸素－窒素混合ガス雰囲気中でアーク放電を用いて亜鉛を蒸発させて窒素ドープされたｐ型酸化亜鉛超微粒子を製造する方法が開示されている。また、特許文献２（特開２００８－２４４３８７号公報）には、窒素ドープされたｐ型酸化亜鉛結晶粒子を用いた発光素子が開示されており、このｐ型酸化亜鉛結晶粒子もまた例えば２０×１０３Ｐａといったガス圧の酸素－窒素混合ガス雰囲気中でアーク放電を用いて亜鉛を蒸発させて作製されている。
特許第４０７２６２０号公報 特開２００８－２４４３８７号公報
　しかしながら、特許文献１及び２に開示されるｐ型酸化亜鉛は粉末形態である。そして、粉末形態のｐ型酸化亜鉛を用いた場合、効率が低い半導体デバイスしか作製できないとの問題があった。そこで、より効率が高い半導体デバイスを作製するためには、膜形態のｐ型酸化亜鉛を製造できる方法が望まれる。
　本発明者らは、今般、ガス圧０．１～１００Ｐａの窒素源及び酸素源を含むガス雰囲気中でアーク放電を用いて成膜し、なおかつ、それにより得られた膜を酸化性雰囲気中でアニールすることで、これまで合成が難しいとされてきたｐ型酸化亜鉛膜を安定的に形成できるとの知見を得た。
　本発明の目的は、ｐ型酸化亜鉛膜を安定的に形成可能な、大面積化にも適した製造方法を提供することにある。
　本発明の一態様によれば、ｐ型酸化亜鉛膜の製造方法であって、
　亜鉛源を含むターゲットと被成膜基板をガス圧０．１～１００Ｐａの窒素源及び酸素源を含むガス雰囲気中に設置し、前記ターゲットをアーク放電に曝して、前記被成膜基板上に亜鉛及び酸素を含む前駆体膜を形成する工程と、
　前記前駆体膜を酸化性雰囲気中でアニールしてｐ型酸化亜鉛膜を得る工程と、
を含む、方法が提供される。
例１において作製された膜のＳＣＭ像（ｐ／ｎ極性像）である。
　定義
　本発明はｐ型酸化亜鉛膜の製造方法である。本明細書において「膜」とは、基板等の固体の表面に構成成分（すなわち酸化亜鉛）が面状に結合してその形態を保持してなるもの、又は基板等の固体の表面に構成粒子（すなわち酸化亜鉛粒子）同士が面状に連結してその形態を保持してなるものを意味する。その意味において、構成粒子同士が連結することなく単に基板上に層状に付着したにすぎない粉末付着物は「膜」とはいえない。そのような「膜」であるか否かは、例えば、膜形成した基板をエタノール等の膜成分と基板が不溶且つ反応しない溶媒に浸漬し、乾燥させた後に、浸漬及び乾燥の前後で状態が変化せずに膜状残留物として残るか否かによって判定可能である。
　ｐ型酸化亜鉛膜の製造方法
　本発明によるｐ型酸化亜鉛膜の製造方法においては、先ず、亜鉛源を含むターゲットと被成膜基板を、ガス圧０．１～１００Ｐａの窒素源及び酸素源を含むガス雰囲気中に設置する。続いて、亜鉛源を含むターゲットをアーク放電に曝して亜鉛源を含むイオン、中性種等からなる蒸気を発生させ、被成膜基板上に亜鉛及び酸素を含む前駆体膜を形成する。次いで、この前駆体膜を酸化性雰囲気中でアニールしてｐ型酸化亜鉛膜を得る。ターゲットをアーク放電に曝して成膜を行う方法は一般的に知られており、アーク放電成膜装置も市販されているが、それによってｐ型酸化亜鉛膜を得たとの報告は、本発明者の知るかぎり今までなされていない。実際、特許文献１及び２において報告されるｐ型酸化亜鉛結晶はいずれも粉末形態であり、膜形態ではない。この点、本発明の方法においては、（特許文献１及び２において採用される２０×１０３Ｐａといったガス圧よりも格段に低い）ガス圧０．１～１００Ｐａの窒素源及び酸素源を含むガス雰囲気中でアーク放電を用いて成膜し、なおかつ、それにより得られた膜を酸化性雰囲気中でアニールすることで、これまで合成が難しいとされてきたｐ型酸化亜鉛膜を安定的に形成することができる。本発明の方法によりｐ型酸化亜鉛膜が得られるメカニズムは定かではないが、亜鉛源を含む蒸気と成膜雰囲気由来の酸素源が反応し、被成膜基板上へ前駆体膜が形成される際に、成膜雰囲気由来の窒素のドープ及び／又は酸化性雰囲気でのアニールによる前駆体膜への酸素の補完に起因するものではないかと推測される（これはあくまで推測であり本発明はこれに限定されるべきではない）。また、このアーク放電を用いた成膜法によれば、ｐ型酸化亜鉛膜を、分子線エピタキシー（ＭＢＥ）法、パルスレーザー堆積（ＰＬＤ）法等の従来法と比べて、より大面積での成膜が可能となるとの利点もある。
（１）アーク放電を介した酸化亜鉛膜の形成
　本発明においては、亜鉛源を含むターゲットと被成膜基板をガス圧０．１～１００Ｐａの窒素源及び酸素源を含むガス雰囲気中に設置し、ターゲットをアーク放電に曝して、この被成膜基板上に、酸化亜鉛でありうる亜鉛及び酸素を含む前駆体からなる膜を形成する。前駆体膜の組成は、ＺｎＯの化学量論組成と同等又はそれに近い酸化亜鉛であってもよいし、酸素が欠乏した酸化亜鉛様組成であってもよい。酸素が欠乏した組成であっても後続のアニール工程において酸素が補完されうるからである。
　アーク放電は公知の条件及び装置を用いて生起させることにより発生させればよく、アーク放電によってターゲットから亜鉛源を含むイオン、中性種等からなる蒸気を発生させることができる。そして、蒸発された亜鉛源を含む蒸気が基板上に上記ガス雰囲気に由来する酸素源と共に基板上に堆積することで、亜鉛及び酸素を含む前駆体膜が形成される。アーク放電の形成は真空チャンバ内において行うのが好ましく、真空チャンバ内は所望の真空度（例えば１×１０－８～１００Ｐａ、好ましくは１×１０－８～０．１Ｐａ）になるまで排気した後、窒素源及び酸素源を含むガス雰囲気を導入すればよい。従って、窒素源及び酸素源を含むガス雰囲気の圧力０．１～１００Ｐａが概ね成膜中の真空チャンバの全圧となる。
　アーク放電を用いた前駆体膜の形成は、アークプラズマガンを用いて行われるのが特に好ましい。アークプラズマガンによれば、アーク放電を介して生じた亜鉛源を含む蒸気を射出口の方向に従って指向性を持たせて放出することができるので、良質の前駆体膜を高い成膜速度で形成することができ、また、大面積化にも適する。例えば、ターゲットを装填したアークプラズマガンを真空装置に取り付け、アークプラズマガンの射出口を真空装置の真空チャンバ内に延出させて成膜を行うのが好ましい。
　雰囲気ガスは、窒素源及び酸素源を含むガスであり、窒素原子と酸素原子を任意の形態で含むガスであれば、多成分系ガス（すなわち混合ガス）でってもよいし、一成分系ガス（例えば窒素酸化物ガス）であってもよい。好ましい雰囲気ガスはＮ２及びＯ２の混合ガスであり、例えば大気でありうる。Ｎ２及びＯ２の混合ガスは、Ｎ２／Ｏ２比がモル基準で９９／１～１０／９０であるのが好ましく、より好ましくは９０／１０～５０／５０である。
　雰囲気ガスの圧力は、０．１～１００Ｐａである。このようなガス圧は特許文献１及び２において例示される２０×１０３Ｐａのガス圧よりも格段に低いものであり、それが（単なる粉末の層状付着ではなく）良質な膜の形成に寄与しているのではないかと考えられる。
　亜鉛源を含むターゲットは、酸化亜鉛膜を構成しうる亜鉛原子の供給源となるものであり、アーク放電に曝した際に蒸発する形態で亜鉛原子をターゲット中に含むものであればよい。亜鉛源を含むターゲットの好ましい例としては、金属亜鉛ターゲット、亜鉛合金ターゲット、導電性酸化亜鉛ターゲットが挙げられる。例えば金属亜鉛ターゲットを用いた場合、前駆体膜は酸素が欠乏した酸化亜鉛様組成となりやすいが、これが後続のアニール工程で酸素が補完されることでｐ型特性を得るのではないかと推測される（これはあくまで推測であり本発明はこれに限定されるべきではない）。
　前駆体膜が形成されるべき基板はｐ型酸化亜鉛膜の品質（例えば結晶性やｐ型特性）を妨げない材質であれば特に限定されない。好ましい基板の例としては、サファイア基板、等が挙げられる。例えば、サファイア基板はａ面、ｃ面、ｍ面、ｒ面等のいずれの面方位のものであってもよい。ｐ型酸化亜鉛膜をホモエピタキシャル成長させるような場合においては、基板として酸化亜鉛単結晶や配向多結晶酸化亜鉛焼結体等が好ましく例示される。一方、ｐｎ接合を用いた発光素子や太陽電池等のデバイスを作製する場合、上記基板上にｎ型酸化亜鉛膜を作製した上にｐ型酸化亜鉛膜を作製してもよい。また、ＬＥＤ等の発光素子を形成する場合、上記ｎ型酸化亜鉛膜上に発光層となり得るノンドープ酸化亜鉛膜を作製し、その上にｐ型酸化亜鉛膜を作製してもよい。
（２）酸化亜鉛膜のアニール処理
　得られた前駆体膜を酸化性雰囲気中でアニール（熱処理）してｐ型酸化亜鉛膜を得る。このアニールを施すことで前駆体膜がｐ型酸化亜鉛膜に改質される。したがって、アニールはｐ型酸化亜鉛膜をもたらす条件で行えばよく、その温度及び時間は特に限定されないが、好ましくは２００～７００℃、より好ましくは３００～５００℃の温度で、所望の時間、例えば１分間～５時間行えばよい。また、酸化性雰囲気は任意の酸化性ガスを含む雰囲気であってよいが、好ましくは大気雰囲気又はＯ２雰囲気である。
　こうして最終的に得られる膜はｐ型酸化亜鉛膜である。得られた酸化亜鉛膜がｐ型か否かの判定は、市販の走査型静電容量顕微鏡（ＳＣＭ）を用いてＳＣＭ像（ｐ／ｎ極性像）を取得することにより行うことができる。また、市販の熱起電力測定器を用いてもｐ型か否かの判定が可能であり、測定箇所の過半数の箇所でｐ型のシグナルが得られればｐ型と判定することができ、例えば測定箇所５箇所中３箇所でｐ型のシグナルが得られればｐ型と判定してよい。あるいは、ホール効果測定など別の方法を用いても酸化亜鉛膜がｐ型か否かの判定が可能である。
　また、ｐ型酸化亜鉛膜の厚さは、用途に応じて適宜決定すればよく特に限定されないが、好ましくは１ｎｍ以上とすることができる。
　本発明を以下の例によってさらに具体的に説明する。
　例１
　ａ面サファイア基板上にアークプラズマガン（ＵＬＶＡＣ社製、ハイパーアークプラズマガンＡＲＬ－３００）（以下、ＡＰＧという）を用いてｐ型酸化亜鉛膜の作製を以下のようにして行った。
　まず、基板として１０ｍｍ×１０ｍｍのサイズのａ面サファイアを用意し、ＡＰＧ用のターゲットとして金属亜鉛（純度＞９９％）を用意した。この金属亜鉛ターゲットを装填したＡＰＧと基板を真空装置に取り付けた。真空装置を作動させて真空チャンバ内を真空度が１×１０－４Ｐａ程度になるまで排気した後、大気を１０Ｐａまで導入し、電圧：１００Ｖ、コンデンサユニット：１０８０μＦ、基板－アノード電極間隔：１５０ｍｍ、パルス数：２５０００パルスの条件でＡＰＧを作動させて成膜を行った。得られた膜の厚さは約２００ｎｍであり、成膜速度は８ｎｍ／１０００パルスであった。なお、膜の厚さは、一部マスクを施して同条件で成膜した試料を別途準備し、この試料の表面プロファイルを小型形状粗さ測定機（Ｔａｙｌｏｒ－Ｈｏｂｓｏｎ社製、Ｆｏｒｍ　Ｔａｌｙｓｕｒｆ　ｐｌｕｓ）を用いて測定することにより行った。こうして成膜されたサファイア基板に、大気雰囲気下４００℃で３．５時間アニール処理を施した。
　得られた膜に対し、封入管式Ｘ線回折装置（ブルカー・エイエックスエス製、Ｄ８　ＡＤＶＡＮＣＥ）を用いて膜の定性分析を行ったところ、酸化亜鉛であることが確認された。また、走査型静電容量顕微鏡（ＳＣＭ）（ブルカー・エイエックス社製、ＮａｎｏＳｃｏｐｅ　ＩＶ）を用いて膜の評価を行ったところ、図１に示されるＳＣＭ像が得られた。図１に示されるＳＣＭ像より、膜の略全面からｐ型のｄＣ／ｄＶ信号が検出され、ｐ型膜が形成されていることが確認された。また、熱起電力測定器（ナプソン製　熱起電力測定器ＰＮ－１２α）を用いて膜のｐｎ判定を行ったところ、測定箇所５箇所中３箇所でｐ型のシグナルが得られた。
　なお、本例ではＳＣＭ及び熱起電力測定器を用いて膜のｐｎ判定を行ったが、ホール効果測定など別の方法を用いて評価しても問題はない。

 

Claims (7)

  1. 　ｐ型酸化亜鉛膜の製造方法であって、
    　亜鉛源を含むターゲットと被成膜基板をガス圧０．１～１００Ｐａの窒素源及び酸素源を含むガス雰囲気中に設置し、前記ターゲットをアーク放電に曝して、前記被成膜基板上に亜鉛及び酸素を含む前駆体膜を形成する工程と、
    　前記前駆体膜を酸化性雰囲気中でアニールしてｐ型酸化亜鉛膜を得る工程と、
    を含む、方法。
  2. 　前記アーク放電を用いた前記前駆体膜の形成が、アークプラズマガンを用いて行われる、請求項１に記載の方法。
  3. 　前記ターゲットが金属亜鉛ターゲットである、請求項１又は２に記載の方法。
  4. 　前記窒素源及び酸素源を含むガスがＮ２及びＯ２の混合ガスである、請求項１～３のいずれか一項に記載の方法。
  5. 　前記混合ガスが大気である、請求項４に記載の方法。
  6. 　前記アニールが２００～７００℃の温度で行われる、請求項１～５のいずれか一項に記載の方法。
  7. 　前記酸化性雰囲気が大気雰囲気又はＯ２雰囲気である、請求項１～６のいずれか一項に記載の方法。
     
PCT/JP2015/064018 2014-05-16 2015-05-15 ｐ型酸化亜鉛膜の製造方法 WO2015174517A1 (ja)

Priority Applications (2)

Application Number Priority Date Filing Date Title
JP2016519311A JP6609764B2 (ja) 2014-05-16 2015-05-15 ｐ型酸化亜鉛膜の製造方法
US15/346,831 US9934968B2 (en) 2014-05-16 2016-11-09 Method for manufacturing p-type zinc oxide film

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2014102384 2014-05-16
JP2014-102384 2014-05-16

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US15/346,831 Continuation US9934968B2 (en) 2014-05-16 2016-11-09 Method for manufacturing p-type zinc oxide film

Publications (1)

Publication Number Publication Date
WO2015174517A1 true WO2015174517A1 (ja) 2015-11-19

Family

ID=54480053

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2015/064018 WO2015174517A1 (ja) 2014-05-16 2015-05-15 ｐ型酸化亜鉛膜の製造方法

Country Status (3)

Country Link
US (1) US9934968B2 (ja)
JP (1) JP6609764B2 (ja)
WO (1) WO2015174517A1 (ja)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2015174517A1 (ja) * 2014-05-16 2015-11-19 国立大学法人名古屋工業大学 ｐ型酸化亜鉛膜の製造方法

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004311702A (ja) * 2003-04-07 2004-11-04 Sumitomo Heavy Ind Ltd 薄膜トランジスタの製造方法および薄膜トランジスタ
JP2005068544A (ja) * 2003-08-25 2005-03-17 Uchitsugu Minami 酸化亜鉛系透明導電膜へのアルミニウムの添加方法
JP2008031035A (ja) * 2006-07-06 2008-02-14 National Institute Of Advanced Industrial & Technology ｐ型酸化亜鉛薄膜及びその作製方法
JP2010280941A (ja) * 2009-06-03 2010-12-16 Nikon Corp 被膜形成物および被膜形成物の製造方法

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4072620B2 (ja) 2003-08-08 2008-04-09 国立大学法人島根大学 酸化亜鉛超微粒子および酸化亜鉛超微粒子の製造方法
CN101577231B (zh) * 2005-11-15 2013-01-02 株式会社半导体能源研究所 半导体器件及其制造方法
US7608308B2 (en) * 2006-04-17 2009-10-27 Imra America, Inc. P-type semiconductor zinc oxide films process for preparation thereof, and pulsed laser deposition method using transparent substrates
JP5277430B2 (ja) 2007-03-29 2013-08-28 国立大学法人島根大学 酸化亜鉛系発光素子
EP2151853A1 (en) * 2007-05-25 2010-02-10 National University Corporation Tohoku University Compound-type thin film, method for compound-type thin film formation, and electronic apparatus using the thin film
KR101746198B1 (ko) * 2009-09-04 2017-06-12 가부시키가이샤 한도오따이 에네루기 켄큐쇼 표시장치 및 전자기기
US8592810B2 (en) * 2009-10-09 2013-11-26 National University Corporation Tohoku University Thin film, method of forming the same, and semiconductor light-emitting element comprising the thin film
US9343310B1 (en) * 2012-06-27 2016-05-17 Nathaniel R Quick Methods of forming conductors and semiconductors on a substrate
WO2015174517A1 (ja) * 2014-05-16 2015-11-19 国立大学法人名古屋工業大学 ｐ型酸化亜鉛膜の製造方法
WO2016031019A1 (ja) * 2014-08-28 2016-03-03 国立大学法人九州大学 レーザ照射装置及びレーザ照射方法

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004311702A (ja) * 2003-04-07 2004-11-04 Sumitomo Heavy Ind Ltd 薄膜トランジスタの製造方法および薄膜トランジスタ
JP2005068544A (ja) * 2003-08-25 2005-03-17 Uchitsugu Minami 酸化亜鉛系透明導電膜へのアルミニウムの添加方法
JP2008031035A (ja) * 2006-07-06 2008-02-14 National Institute Of Advanced Industrial & Technology ｐ型酸化亜鉛薄膜及びその作製方法
JP2010280941A (ja) * 2009-06-03 2010-12-16 Nikon Corp 被膜形成物および被膜形成物の製造方法

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
N.H. ERDOGAN ET AL.: "Effect of the oxidation temperature on microstructure and conductivity of ZnxNy thin films and their conversion into p-type ZnO:N films", APPLIED SURFACE SCIENCE, vol. 271, 20 January 2013 (2013-01-20), pages 70 - 76, XP029003397 *
Y.G. WANG ET AL.: "Observations of nitrogen- related photoluminescence bands from nitrogen- doped ZnO films", JOURNAL OF CRYSTAL GROWTH, vol. 252, no. Issue 1-3, 2003, pages 265 - 269, XP027392421 *

Also Published As

Publication number Publication date
JP6609764B2 (ja) 2019-11-27
US20170053801A1 (en) 2017-02-23
US9934968B2 (en) 2018-04-03
JPWO2015174517A1 (ja) 2017-04-20

Similar Documents

Publication Publication Date Title
KR101467118B1 (ko) 스퍼터링 방법을 이용한 산화갈륨 나노와이어의 제조 방법
Thakur et al. Electronic structure of GaN nanowall network analysed by XPS
Kushvaha et al. Structural, optical and electronic properties of homoepitaxial GaN nanowalls grown on GaN template by laser molecular beam epitaxy
JP7031181B2 (ja) 窒化ガリウム系膜ならびにその製造方法
US7842539B2 (en) Zinc oxide semiconductor and method of manufacturing the same
JP6740623B2 (ja) 窒化ガリウム系膜ならびにその製造方法
TW201417335A (zh) 磊晶膜形成方法、濺鍍裝置、半導體發光元件之製造方法、半導體發光元件及照明裝置
JP5490368B2 (ja) エピタキシャル薄膜の形成方法及び半導体基板の製造方法
JP6609764B2 (ja) ｐ型酸化亜鉛膜の製造方法
US10526723B2 (en) System and method for increasing III-nitride semiconductor growth rate and reducing damaging ion flux
Nguyen et al. Fabrication of ZnO nanorods for gas sensing applications using hydrothermal method
Hsu et al. Indium-diffused ZnO nanowires synthesized on ITO-buffered Si substrate
Pang et al. Growth of wurtzite and zinc-blende phased GaN on silicon (100) substrate with sputtered AlN buffer layer
JP2007049032A (ja) 酸化物結晶の成長装置及びそれを使用した製造方法
Zherikhin et al. Laser deposition of ZnO films on silicon and sapphire substrates
JP5936028B2 (ja) ウルツ鉱型結晶膜およびその製造方法
Biyikli et al. Low-Temperature Self-Limiting Growth of III-Nitride Thin Films by Plasma-Enhanced Atomic Layer Deposition
JP6392206B2 (ja) 炭素ドープ酸化亜鉛膜及びその製造方法
US20240242964A1 (en) Crystalline strontium titanate (sto) and method for deposition of the sto on a substrate
JP5176054B2 (ja) 薄膜形成装置及び薄膜形成方法
Phan et al. Defect modification in enhancing thermopower factor of ZnO films without doping
Khudobenko et al. Pulsed laser deposition of ZnO thin films in silicon and sapphire
Natarajan Optimisation and fabrication of ultra violet emitting CuC1 thin films by RF sputtering
Nagata et al. Effects of single-crystalline GaN target on GaN thin films in pulsed laser deposition process
JP2013147683A (ja) 酸化亜鉛薄膜

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 15792729

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 2016519311

Country of ref document: JP

Kind code of ref document: A

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 15792729

Country of ref document: EP

Kind code of ref document: A1