JPH05231849A - Measurement method of particle diameter and average particle diameter of ultrafine particle - Google Patents
Measurement method of particle diameter and average particle diameter of ultrafine particleInfo
- Publication number
- JPH05231849A JPH05231849A JP6930192A JP6930192A JPH05231849A JP H05231849 A JPH05231849 A JP H05231849A JP 6930192 A JP6930192 A JP 6930192A JP 6930192 A JP6930192 A JP 6930192A JP H05231849 A JPH05231849 A JP H05231849A
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- Prior art keywords
- particle diameter
- ultrafine particles
- particle size
- ultrafine
- energy
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Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、１０μｍ以下の微小領
域に存在する超微粒子の粒径及び平均粒径の測定方法に
関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring the particle size and average particle size of ultrafine particles existing in a minute region of 10 μm or less.
【０００２】[0002]
【従来の技術】半導体及び金属の超微粒子は、強い光学
非線形性を示すことから、新しい光学材料もしくは電子
材料として注目を集め、多くの研究が行われている。こ
の超微粒子の性質は量子サイズ効果と関連していること
が知られており、超微粒子の粒径に大変敏感であること
が特徴である。この為、この研究において超微粒子の粒
径及び平均粒径を測定することが大変重要である。この
超微粒子の粒径及び平均粒径を測定する方法として、以
下に示す二通りの方法が従来から用いられている。一つ
は、透過電子顕微鏡を用いる方法である。この方法は、
粒径等の測定対象である超微粒子試料を１０ｎｍ程度に
薄くした上で、透過電子顕微鏡を用いて多数の超微粒子
を直接観察、若しくは銀塩フィルムに撮影することによ
って、個々の超微粒子の粒径を測定し、粒径及び平均粒
径を求める方法である（以下、直接観察法と呼ぶ）。二
つめは、Ｘ線を用いる方法であり、この方法の概略は以
下の様である。大きな結晶にＸ線を当てたときに得られ
る回折図形は、細いリングもしくは小さなスポットから
なる。これに対して、超微粒子から得られる回折図形
は、幅の広いリングからなる。この広がりを表す半値幅
Ｂは、超微粒子の粒径Ｄに対して下式で表されることが
知られている。 Ｂ＝０．９λ／Ｄ／ｃｏｓθ ここで、λはＸ線の波長、θはＢｒａｇｇ角である。こ
の式を用いることにより、Ｘ線回折線の半値幅から超微
粒子の平均粒径を求めることが出来る（以下、半値幅法
と呼ぶ）。ところで、超微粒子を新規の光学的若しくは
電子的なデバイスとして応用する際は、そのデバイスの
構造はμｍオーダーになる。この為、約１０μｍ以下の
微小領域に存在する超微粒子の粒径及び平均粒径を測定
することが必要になってくる。2. Description of the Related Art Ultrafine particles of semiconductors and metals show a strong optical nonlinearity, and therefore have attracted attention as new optical materials or electronic materials, and many studies have been conducted. It is known that the properties of the ultrafine particles are associated with the quantum size effect, and is characterized by being extremely sensitive to the particle size of the ultrafine particles. Therefore, it is very important to measure the particle size and average particle size of ultrafine particles in this study. As the method for measuring the particle size and average particle size of the ultrafine particles, the following two methods have been conventionally used. One is a method using a transmission electron microscope. This method
Particles of individual ultrafine particles can be obtained by thinning the ultrafine particle sample to be measured such as particle size to about 10 nm and then directly observing a large number of ultrafine particles with a transmission electron microscope or photographing on a silver salt film. This is a method of measuring the diameter and obtaining the particle diameter and the average particle diameter (hereinafter referred to as the direct observation method). The second is a method using X-rays, and the outline of this method is as follows. The diffraction pattern obtained when a large crystal is exposed to X-rays consists of a thin ring or a small spot. On the other hand, the diffraction pattern obtained from the ultrafine particles consists of a wide ring. It is known that the half width B representing this spread is expressed by the following equation with respect to the particle diameter D of the ultrafine particles. B = 0.9λ / D / cos θ where λ is the wavelength of the X-ray and θ is the Bragg angle. By using this formula, the average particle size of the ultrafine particles can be obtained from the half-value width of the X-ray diffraction line (hereinafter referred to as the half-value width method). By the way, when the ultrafine particles are applied as a new optical or electronic device, the structure of the device is on the order of μm. For this reason, it becomes necessary to measure the particle size and average particle size of the ultrafine particles existing in a minute region of about 10 μm or less.
【０００３】[0003]
【発明が解決しようとしている課題】しかしながら、上
記の直接観察法では、約１０μｍ以下の微小領域に存在
する特定な超微粒子の単一粒径を測定することは出来る
ものの、平均粒径を測定するには、数百から千個程度の
多数の超微粒子に対して夫々粒径を測定しなければなら
ない為、大変時間を要するという問題がある。又、単一
粒径と平均粒径のどちらを測定する場合でも、測定する
試料の形態に制限があり、測定対象試料を電子線が透過
する１０ｎｍ程度まで薄くする必要がある為、観察試料
を作製するまでに多くの時間を要するという問題があ
る。一方、半値幅法では、ある特定な約１０μｍ以下の
微小領域にＸ線を選択的に当てることは出来ない為、こ
の測定方法を適用することは不可能であるという問題が
ある。そこで本発明の目的は、容易に１０μｍ以下の微
小領域に存在する超微粒子の粒径及び平均粒径を測定す
ることが出来る新規な方法を提供することにある。However, although the above-mentioned direct observation method can measure the single particle size of specific ultrafine particles existing in a minute region of about 10 μm or less, it measures the average particle size. However, there is a problem that it takes a lot of time because the particle size of each of a large number of hundreds to thousands of ultrafine particles must be measured. In addition, when measuring either the single particle size or the average particle size, there is a limitation in the form of the sample to be measured, and the sample to be measured needs to be thinned to about 10 nm through which the electron beam passes. There is a problem that it takes a lot of time to manufacture. On the other hand, the full width at half maximum method has a problem in that it is impossible to apply this measuring method because it is not possible to selectively apply X-rays to a specific minute area of about 10 μm or less. Therefore, an object of the present invention is to provide a novel method capable of easily measuring the particle size and the average particle size of ultrafine particles existing in a minute region of 10 μm or less.
【０００４】[0004]
【課題を解決する為の手段】本発明の目的は、以下の発
明によって達成される。即ち本発明は、１０μｍ以下の
微小領域に存在する超微粒子の粒径及び平均粒径測定方
法において、電子線源と電子エネルギー分析装置を使用
することを特徴とする超微粒子の粒径及び平均粒径測定
方法である。The objects of the present invention are achieved by the following inventions. That is, the present invention provides a method for measuring the particle size and average particle size of ultrafine particles existing in a fine region of 10 μm or less, characterized by using an electron beam source and an electron energy analyzer. This is a diameter measuring method.
【０００５】[0005]
【作用】本発明の超微粒子の粒径及び平均粒径測定方法
は、発明者が鋭意研究した結果見出した、超微粒子内に
発生するプラズモンのエネルギーが粒径に応じて変化す
る特徴を利用するものである。即ち、プラズモンのエネ
ルギーを電子エネルギー損失分光法を用いて測定すれ
ば、そのエネルギーから超微粒子の粒径及び平均粒径を
容易に求めることが出来る。The method for measuring the particle size and average particle size of the ultrafine particles of the present invention utilizes the characteristic of the plasmon energy generated in the ultrafine particles, which is found by the inventors as a result of intensive research. It is a thing. That is, if the energy of plasmons is measured using electron energy loss spectroscopy, the particle size and average particle size of ultrafine particles can be easily obtained from the energy.
【０００６】[0006]
【好ましい実施態様】次に、好ましい実施態様を挙げ、
本発明を更に詳細に説明する。先ず、本発明の超微粒子
の粒径及び平均粒径測定方法の測定原理を以下に説明す
る。本発明者の鋭意研究の結果、図１に示す様に超微粒
子中に発生するプラズモンのエネルギーは、粒径が小さ
くなると量子サイズ効果の影響を受けて、大きな結晶中
に発生するプラズモンのエネルギーよりも大きくなるこ
とを見出した。更に、詳細な研究を進めた結果、本発明
者はこのプラズモンのエネルギーＥと超微粒子の粒径ｄ
との間に、下記の（１）式の関係があることを知見し
た。 Ｅ（ｄ）＝ＥO（１＋ｈ2π2／ｍＥｇｄ2） （１） ここで、Ｅは大きな結晶において観測されるプラズモン
のエネルギー、Ｅｇはバンドギャップ、ｍは電子の有効
質量、ｈはプランク定数を２πで割った値である。従っ
て、超微粒子中のプラズモンエネルギーを測定すれば、
その超微粒子の単一粒径は、上記の式から算出される。
更に、粒径分布を持った複数の超微粒子のプラズモンエ
ネルギーを測定すれば、その複数の超微粒子の平均粒径
も得ることが出来る。Preferred Embodiments Next, preferred embodiments will be mentioned.
The present invention will be described in more detail. First, the measurement principle of the method for measuring the particle size and average particle size of ultrafine particles of the present invention will be described below. As a result of the inventor's earnest research, as shown in FIG. 1, the energy of plasmons generated in ultrafine particles is affected by the quantum size effect when the particle size becomes smaller, and is smaller than the energy of plasmons generated in large crystals. I also found that it will grow. As a result of further detailed research, the present inventor has found that the energy E of this plasmon and the particle diameter d of the ultrafine particles.
It has been found that there is a relation of the following formula (1) between and. E (d) = E O ( 1 + h 2 π 2 / mEgd 2) (1) where, E is the energy of plasmon observed in large crystals, Eg is the band gap, m is the effective electron mass, h is Planck's constant Is divided by 2π. Therefore, if you measure the plasmon energy in ultrafine particles,
The single particle size of the ultrafine particles is calculated from the above formula.
Furthermore, by measuring the plasmon energy of a plurality of ultrafine particles having a particle size distribution, the average particle size of the plurality of ultrafine particles can also be obtained.
【０００７】上記のプラズモンエネルギーは、以下に述
べる様に電子エネルギー損失スペクトルを測定すること
により求めることが出来る。即ち、超微粒子の約１０μ
ｍ以下の微小領域に電子線を当てた状態で電子エネルギ
ー損失スペクトルを測定すると、その微小領域に存在す
る超微粒子の平均粒径に相当するプラズモンのエネルギ
ーと一致したところに損失ピークが現れる。従って、電
子エネルギー損失スペクトルを測定すれば、このエネル
ギー損失スペクトルのピーク位置に相当するプラズモン
エネルギーが求められる。この様にして、プラズモンエ
ネルギーが求められれば、上記の（１）式の関係から、
その微小領域に存在する超微粒子の平均粒径を求めるこ
とが出来る。又、電子線を絞って超微粒子の単一粒子の
電子エネルギー損失スペクトルを同様に測定し、プラズ
モンエネルギーを求めれば、単一粒子の粒径を求めるこ
とが出来る。The above plasmon energy can be obtained by measuring the electron energy loss spectrum as described below. That is, about 10μ of ultrafine particles
When an electron energy loss spectrum is measured with an electron beam applied to a minute region of m or less, a loss peak appears at a position corresponding to the plasmon energy corresponding to the average particle size of ultrafine particles existing in the minute region. Therefore, if the electron energy loss spectrum is measured, the plasmon energy corresponding to the peak position of this energy loss spectrum can be obtained. If the plasmon energy is obtained in this way, from the relation of the above equation (1),
The average particle diameter of the ultrafine particles existing in the minute area can be obtained. Further, the particle size of the single particle can be obtained by similarly measuring the electron energy loss spectrum of the single particle of the ultrafine particles by narrowing down the electron beam and obtaining the plasmon energy.
【０００８】本発明方法で必要な上記のプラズモンエネ
ルギーの測定装置は、電子線源と、電場又は磁場を用い
た電子のエネルギー分析装置だけである為、他の如何な
る真空容器とも容易に組み合わせることが可能である。
又、本発明方法で粒径及び平均粒径を測定することが出
来る超微粒子材料としては、Ｃ、Ｓｉ、Ｇｅ等の半導体
材料やその合金、Ｓｉ−Ｏ、Ｓｎ−Ｏ、Ｔｉ−Ｏ等の酸
化物、Ｓｉ−Ｎ、Ｔｉ−Ｎ、Ｂ−Ｎ等の窒化物、Ｓｉ−
Ｃ、Ｗ−Ｃ等の炭化物等、半導体及び絶縁体材料の全て
のものに適用することが出来る。中でも、Ｓｉ系の超微
粒子に好ましく適用される。Since the plasmon energy measuring device required for the method of the present invention is only an electron beam source and an electron energy analyzer using an electric field or a magnetic field, it can be easily combined with any other vacuum container. It is possible.
Further, as the ultrafine particle material whose particle diameter and average particle diameter can be measured by the method of the present invention, semiconductor materials such as C, Si and Ge and alloys thereof, Si—O, Sn—O, Ti—O and the like can be used. Oxide, Si-N, Ti-N, BN and other nitrides, Si-
It can be applied to all semiconductor and insulator materials such as C and WC carbides. Above all, it is preferably applied to Si-based ultrafine particles.
【０００９】[0009]
【実施例】次に、本発明の実施例を挙げて本発明を更に
詳細に説明する。 実施例１ 図２は、マイクロ波プラズマ法によって異なる条件で作
成された二種類のＳｉ超微粒子についての電子エネルギ
ー損失スペクトルである。該スペクトルは、透過電子顕
微鏡に取り付けられた電子エネルギー損失分光装置を用
い、０．５μｍの微小領域で得られた電子エネルギー損
失スペクトルである。このスペクトルに見られるプラズ
モン励起に伴う損失ピークの位置を図１と比較すれば、
夫々の材料に対して表１の様な平均粒径が求まる。上記
と同一のＳｉ超微粒子について、従来行われている直接
観察法で平均粒径を夫々求め上記の結果と比較すると、
表１に示した様によい一致を示しており、本発明方法に
よって得られる平均粒径は、従来行われている直接観察
法と同等の精度を有することがわかる。EXAMPLES Next, the present invention will be described in more detail with reference to examples of the present invention. Example 1 FIG. 2 is an electron energy loss spectrum for two types of Si ultrafine particles prepared under different conditions by the microwave plasma method. The spectrum is an electron energy loss spectrum obtained in a minute region of 0.5 μm using an electron energy loss spectroscope attached to a transmission electron microscope. Comparing the position of the loss peak due to plasmon excitation seen in this spectrum with FIG.
The average particle size as shown in Table 1 is obtained for each material. For the same Si ultrafine particles as above, the average particle diameters were respectively obtained by the conventional direct observation method and compared with the above results,
As shown in Table 1, there is good agreement, and it can be seen that the average particle size obtained by the method of the present invention has the same accuracy as that of the conventional direct observation method.
【００１０】[0010]
【表１】 [Table 1]
【００１１】実施例２ 図３は、１インチのＳｉウエハー上にマイクロ波プラズ
マ法によって堆積させたシリコン超微粒子について、円
筒鏡型電子エネルギー分析装置を用いて、ウエハー上の
微小部分（３μｍ）から得られた、電子エネルギー損失
スペクトルである。但し、このスペクトルはピーク位置
を明瞭に表示する為に、二次微分の形で描かれている。
このスペクトルでも、実施例１と同様に、プラズモン励
起に伴う損失ピークが見られており、このピーク位置か
らＳｉ超微粒子についての平均粒径が求められた。又、
ウエハー上の広い領域にＸ線を当てることによる半値幅
法を用いて、同一のＳｉ超微粒子について平均粒径を測
定したところ、上記の結果とよい一致を示した。このこ
とから本発明方法によって得られる平均粒径は、従来行
われている半値幅法と同等の精度を有することがわか
る。Example 2 FIG. 3 shows silicon ultrafine particles deposited on a 1-inch Si wafer by a microwave plasma method from a minute portion (3 μm) on the wafer using a cylindrical mirror electron energy analyzer. It is the obtained electron energy loss spectrum. However, this spectrum is drawn in the form of the second derivative in order to clearly display the peak position.
Also in this spectrum, as in Example 1, a loss peak associated with plasmon excitation was observed, and the average particle size of the Si ultrafine particles was determined from this peak position. or,
When the average particle size of the same Si ultrafine particles was measured using the half-width method by applying X-rays to a wide area on the wafer, the results were in good agreement with the above results. From this, it is understood that the average particle diameter obtained by the method of the present invention has the same accuracy as that of the half-width method which has been conventionally performed.
【００１２】[0012]
【発明の効果】以上説明した様に、本発明の超微粒子の
粒径及び平均粒径の測定方法により、１０μｍ以下の微
小領域に存在する超微粒子の粒径及び平均粒径を、電子
線源と電子エネルギー分析装置を使用するだけで、容易
に測定することが出来る。As described above, according to the method for measuring the particle size and average particle size of ultrafine particles of the present invention, the particle size and average particle size of the ultrafine particles existing in a fine region of 10 μm or less are determined by using an electron beam source. It is possible to measure easily just by using an electronic energy analyzer.
【図１】図１は、超微粒子中に発生するプラズモンエネ
ルギーと粒径との関係を示す図である。FIG. 1 is a diagram showing a relationship between plasmon energy generated in ultrafine particles and particle diameter.
【図２】図２は、マイクロ波プラズマ法によって異なる
条件で作成された二種類のＳｉ超微粒子についての電子
エネルギー損失スペクトルである。FIG. 2 is an electron energy loss spectrum for two types of Si ultrafine particles prepared under different conditions by a microwave plasma method.
【図３】図３は、円筒鏡型電子エネルギー分析装置を用
い測定した、Ｓｉウエハー上にマイクロ波プラズマ法に
より堆積させたＳｉ超微粒子のウエハー上の微小部分
（３μｍ）から得られた電子エネルギー損失スペクトル
である。FIG. 3 is an electron energy obtained from a minute portion (3 μm) on a wafer of Si ultrafine particles deposited by a microwave plasma method on a Si wafer, measured using a cylindrical mirror electron energy analyzer. It is a loss spectrum.
Claims (3)
粒子の粒径及び平均粒径測定方法において、電子線源と
電子エネルギー分析装置を使用することを特徴とする超
微粒子の粒径及び平均粒径測定方法。1. A method for measuring the particle size and average particle size of ultrafine particles existing in a fine region of 10 μm or less, characterized in that an electron beam source and an electron energy analyzer are used. Diameter measurement method.
り測定される電子エネルギー損失スペクトルから超微粒
子内に発生するプラズモンエネルギーを求めた後、超微
粒子の粒径とその超微粒子内に発生するプラズモンエネ
ルギーとの間に存在する相関関係を利用して超微粒子の
粒径及び平均粒径を求めることを特徴とする請求項１に
記載の超微粒子の粒径及び平均粒径測定方法。2. The particle size of ultrafine particles and the plasmon energy generated in the ultrafine particles are obtained after determining the plasmon energy generated in the ultrafine particles from the electron energy loss spectrum measured by an electron beam source and an electron energy analyzer. The particle diameter and the average particle diameter of the ultrafine particles according to claim 1, wherein the particle diameter and the average particle diameter of the ultrafine particles are obtained by utilizing the correlation existing between and.
に記載の超微粒子の粒径及び平均粒径測定方法。3. The ultrafine particles are Si ultrafine particles.
The method for measuring the particle diameter and the average particle diameter of the ultrafine particles according to.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6930192A JP2846520B2 (en) | 1992-02-20 | 1992-02-20 | How to measure the particle size or average particle size of ultrafine particles |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6930192A JP2846520B2 (en) | 1992-02-20 | 1992-02-20 | How to measure the particle size or average particle size of ultrafine particles |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH05231849A true JPH05231849A (en) | 1993-09-07 |
| JP2846520B2 JP2846520B2 (en) | 1999-01-13 |
Family
ID=13398612
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP6930192A Expired - Fee Related JP2846520B2 (en) | 1992-02-20 | 1992-02-20 | How to measure the particle size or average particle size of ultrafine particles |
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| Country | Link |
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|---|---|---|---|---|
| CN108072595A (en) * | 2017-12-04 | 2018-05-25 | 株洲硬质合金集团有限公司 | With the method for WC grain sectional area particle diameter distribution characterization Mathematical Analysis of Al-li Alloy Containing Rare Earth structure |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108072595A (en) * | 2017-12-04 | 2018-05-25 | 株洲硬质合金集团有限公司 | With the method for WC grain sectional area particle diameter distribution characterization Mathematical Analysis of Al-li Alloy Containing Rare Earth structure |
| CN108072595B (en) * | 2017-12-04 | 2020-11-20 | 株洲硬质合金集团有限公司 | Method for representing hard alloy structure by using WC crystal grain sectional area grain size distribution |
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