JPH0720021A - Secondary ion-mass spectrometry for insulator - Google Patents
Secondary ion-mass spectrometry for insulatorInfo
- Publication number
- JPH0720021A JPH0720021A JP5146174A JP14617493A JPH0720021A JP H0720021 A JPH0720021 A JP H0720021A JP 5146174 A JP5146174 A JP 5146174A JP 14617493 A JP14617493 A JP 14617493A JP H0720021 A JPH0720021 A JP H0720021A
- Authority
- JP
- Japan
- Prior art keywords
- sample
- insulator
- particle layer
- measurement
- mass spectrometry
- Prior art date
- Legal status (The legal status 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 status listed.)
- Pending
Links
- 239000012212 insulator Substances 0.000 title claims abstract description 17
- 238000001004 secondary ion mass spectrometry Methods 0.000 title abstract description 12
- 238000000034 method Methods 0.000 claims abstract description 27
- 238000005259 measurement Methods 0.000 claims abstract description 25
- 150000002500 ions Chemical group 0.000 claims abstract description 20
- 238000004949 mass spectrometry Methods 0.000 claims abstract description 9
- 238000004458 analytical method Methods 0.000 claims abstract description 8
- 238000010884 ion-beam technique Methods 0.000 claims abstract description 8
- 239000002245 particle Substances 0.000 claims abstract description 7
- 238000001659 ion-beam spectroscopy Methods 0.000 claims abstract description 5
- 239000002184 metal Substances 0.000 claims abstract description 3
- 230000001678 irradiating effect Effects 0.000 claims abstract 2
- 239000011882 ultra-fine particle Substances 0.000 claims description 8
- 239000011810 insulating material Substances 0.000 claims description 7
- 239000000126 substance Substances 0.000 claims description 4
- 238000010304 firing Methods 0.000 claims 1
- 239000010419 fine particle Substances 0.000 abstract 5
- 239000010410 layer Substances 0.000 abstract 5
- 239000004020 conductor Substances 0.000 abstract 1
- 239000002344 surface layer Substances 0.000 abstract 1
- 239000010408 film Substances 0.000 description 13
- 238000007740 vapor deposition Methods 0.000 description 9
- 238000010894 electron beam technology Methods 0.000 description 6
- 238000004544 sputter deposition Methods 0.000 description 5
- 238000000151 deposition Methods 0.000 description 4
- 238000000059 patterning Methods 0.000 description 4
- 229910004298 SiO 2 Inorganic materials 0.000 description 3
- 230000008021 deposition Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000003472 neutralizing effect Effects 0.000 description 2
- 238000002203 pretreatment Methods 0.000 description 2
- 239000000758 substrate Substances 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 230000001133 acceleration Effects 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 238000003763 carbonization Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 238000001465 metallisation Methods 0.000 description 1
- 239000011368 organic material Substances 0.000 description 1
- 238000004445 quantitative analysis Methods 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
Landscapes
- Analysing Materials By The Use Of Radiation (AREA)
- Sampling And Sample Adjustment (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、二次イオン質量分析法
を用いた絶縁物の分析、特にその質量分析法における試
料の前処理法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to analysis of insulators using secondary ion mass spectrometry, and more particularly to a sample pretreatment method in the mass spectrometry.
【０００２】[0002]
【従来の技術】二次イオン質量分析法（ＳＩＭＳ）は、
分析の際に二次イオンビームを用いるため、測定試料が
絶縁物である場合は、イオンビームによる電荷や二次的
に発生する電子やイオンにより、試料の表面にいわゆる
チャージアップと呼ばれる帯電現象が生じてしまう。こ
のため、試料表面の電位が変化して、二次イオンの軌道
も変化して、二次イオンの検出は困難となってしまう。2. Description of the Related Art Secondary ion mass spectrometry (SIMS)
Since the secondary ion beam is used for the analysis, when the measurement sample is an insulator, the surface of the sample may be charged by the so-called charge-up phenomenon due to the charges due to the ion beam and the secondary electrons and ions. Will occur. For this reason, the potential of the sample surface changes, the trajectory of the secondary ions also changes, and it becomes difficult to detect the secondary ions.
【０００３】そこで従来、二次イオン質量分析法による
絶縁物分析で帯電を防止する方法としては、（１）マイ
ナスのイオンビームを一次イオンとして用いることによ
り、二次電子放出によるプラス電荷蓄積を回避する方
法、（２）電子ビーム照射により、マイナス電荷を試料
に直接与え、試料表面のプラス電荷を中和する方法、
（３）絶縁物の表面電荷を導電性の物質を介して逃す方
法、または（４）磁石を用いて帯電電荷を中和する方法
の４種類の方法が主としてとられてきた。Therefore, conventionally, as a method of preventing charging in an insulator analysis by secondary ion mass spectrometry, (1) by using a negative ion beam as a primary ion, positive charge accumulation due to secondary electron emission is avoided. Method, (2) a method of directly applying a negative charge to the sample by electron beam irradiation to neutralize the positive charge on the sample surface,
Four methods have been mainly adopted: (3) a method of releasing the surface charge of an insulator through a conductive substance, or (4) a method of neutralizing the charged charge by using a magnet.
【０００４】[0004]
【発明が解決しようとする課題】しかしながら、上記
（１）〜（４）の対策には以下の問題点があった。However, the measures (1) to (4) have the following problems.
【０００５】（１）の方法は試料の二次電子放出効率や
試料の電位に大きく依存するため、全ての絶縁物におい
て使用できるわけではなく、単独ではあまり有効な手段
ではない。そこで、（２）または（３）の方法との併用
で行なわれることが多い。Since the method (1) depends largely on the secondary electron emission efficiency of the sample and the potential of the sample, it cannot be used for all insulators and is not a very effective means by itself. Therefore, it is often carried out in combination with the method (2) or (3).
【０００６】（２）の方法は、従来最も多く用いられて
きた方法であるが、以下の３つの問題点がある。The method (2) is the most frequently used method in the past, but has the following three problems.
【０００７】ａ）引き出し電極をグランドとし、試料に
電圧を印加して測定するタイプのＳＩＭＳでは、例え
ば、一次イオンをプラスとし二次イオンをプラスとして
測定する場合には、プラスの電荷をかけて測定すること
になる。この場合には、ある程度の加速電圧の電子銃で
中和することができ、チャージ補正が可能である。しか
しながら、二次イオンをマイナスで測定したい場合には
数ｋＶの電子銃では試料まで電子が届かず、チャージ補
正ができない。A) In the SIMS of the type in which a voltage is applied to a sample with the extraction electrode as the ground, a positive charge is applied when the primary ion is positive and the secondary ion is positive. It will be measured. In this case, the charge can be corrected by neutralizing with an electron gun having an acceleration voltage to some extent. However, when it is desired to measure the secondary ions with a negative value, electrons cannot reach the sample with an electron gun of several kV, and charge correction cannot be performed.
【０００８】ｂ）電子線損傷を起こす試料や低融点の材
料からなる試料には適用できない。例えば、有機材料の
場合、電子線を照射することによってカーボンの結合状
態が変化し、炭化を起こすこともある。B) It cannot be applied to a sample that causes electron beam damage or a sample made of a low melting point material. For example, in the case of an organic material, the bond state of carbon may be changed by irradiation with an electron beam, and carbonization may occur.
【０００９】ｃ）再現性が悪い。帯電防止に最適な電子
ビーム照射の量は一次イオンビーム量と二次電子放出量
との関係で決定されることから、長時間の電子ビーム照
射での、一次イオンビーム量と二次電子放出量の変動に
より、得られる二次イオンの量が変動し、安定した測定
が望めない。また、長時間の電子ビーム照射によって試
料が温度上昇し、測定が不安定となることもある。 （３）の方法としては、導電性のメッシュを絶縁物の表
面に接触させる手法または導電性の薄膜を絶縁物表面に
蒸着させるという手法が一般的であった。C) Poor reproducibility. Since the optimum amount of electron beam irradiation for antistatic is determined by the relationship between the amount of primary ion beam and the amount of secondary electron emission, the amount of primary ion beam and the amount of secondary electron emission during long-time electron beam irradiation The amount of the secondary ions obtained will fluctuate due to the fluctuation of, and stable measurement cannot be expected. Further, the temperature of the sample rises due to the long-time electron beam irradiation, which may make the measurement unstable. As the method (3), a method of bringing a conductive mesh into contact with the surface of the insulator or a method of depositing a conductive thin film on the surface of the insulator has been generally used.
【００１０】ところが、前者のメッシュ法の場合、メッ
シュの接触が不完全であると帯電防止効果がなかった
り、接触の仕方、接触点の数などが影響するために、再
現性の良いデータを得ることが困難であった。また、二
次イオンを検出する領域が数１００μｍであるのが普通
であることから、分析中の絶縁物露出部分がそれよりも
大きくなるようなメッシュを選択することになって、帯
電防止効果があまり望めなくなる。However, in the former mesh method, if the mesh contact is incomplete, there is no antistatic effect, the way of contact, the number of contact points, etc. affect, so that data with good reproducibility is obtained. Was difficult. In addition, since the region for detecting secondary ions is usually several 100 μm, it is necessary to select a mesh in which the exposed portion of the insulator during analysis is larger than that, and the antistatic effect is improved. I can't hope too much.
【００１１】また、後者の蒸着法では測定プロファイル
に蒸着物質の影響が出て、表面付近の詳細なデータを得
ることができない。さらに、最も簡便な蒸着方法として
２極直流スパッタリング法または加熱蒸着法が用いられ
るが、これらの方法で得られる蒸着膜は蒸着粒子が非常
に大きくしかも不均一で、蒸着膜厚や材料によっては膜
が島状構造になることもあり、また、平坦性も良好では
ない。このため、測定箇所が全く同一でない限り、同様
のスペクトルを得ることは不可能とされ、再現性が悪
い。In the latter vapor deposition method, the measurement profile is affected by the vapor deposition substance, and detailed data near the surface cannot be obtained. Further, as the simplest vapor deposition method, a bipolar direct current sputtering method or a heated vapor deposition method is used. The vapor deposition film obtained by these methods has very large vapor deposition particles and is non-uniform. May have an island structure, and the flatness is not good. Therefore, it is impossible to obtain a similar spectrum unless the measurement points are exactly the same, and the reproducibility is poor.
【００１２】（４）の方法は最近開発されたものであ
り、今後その有用性アップが期待されるが、現在のとこ
ろ、試料の下部に磁石を設置しなければならないなど操
作性の問題等の改善が必要である。The method (4) has been recently developed, and its usefulness is expected to increase in the future. However, at present, there is a problem in operability such as a magnet having to be installed under the sample. Needs improvement.
【００１３】本発明は上述の問題点を改善し、二次イオ
ン質量分析法による絶縁物分析を容易にすることを目的
としてなされたものである。The present invention has been made for the purpose of improving the above problems and facilitating the analysis of insulators by secondary ion mass spectrometry.
【００１４】[0014]
【課題を解決するための手段】本発明は、一次イオンビ
ームを絶縁物試料に照射し、試料表面から発生する二次
イオンを引き出して質量分析を行なうことによりその試
料の定性・定量を行なう絶縁物の二次イオン質量分析法
において、絶縁物試料の表面に導電性超微粒子層を形成
し、それを用いて測定を行なうことを特徴とする絶縁物
の二次イオン質量分析法を提供する。According to the present invention, an insulator sample is irradiated with a primary ion beam, secondary ions generated from the sample surface are extracted, and mass analysis is performed to perform qualitative and quantitative determination of the sample. In a secondary ion mass spectrometric method for an insulating material, a secondary ion mass spectrometric method for an insulating material is provided, in which a conductive ultrafine particle layer is formed on the surface of an insulating material sample and measurement is performed using the layer.
【００１５】形成される超微粒子層の層形状が均一かつ
平坦であるためには、粒子径は０．００５μｍ以下とす
るのが望ましく、０．００３μｍ以下とするのが最適で
ある。このような超微粒子層を形成するには、（１）イ
オンビームスパッタ法、または（２）絶縁物表面に有機
金属を含む溶液を塗布して焼成する方法などが適してい
る。In order for the ultrafine particle layer to be formed to have a uniform and flat layer shape, the particle size is preferably 0.005 μm or less, and most preferably 0.003 μm or less. In order to form such an ultrafine particle layer, (1) an ion beam sputtering method, or (2) a method of applying a solution containing an organic metal on the surface of an insulating material and baking it is suitable.
【００１６】[0016]
（実施例１）通常測定が困難とされているＳｉ基板上Ｓ
ｉＯ2膜中の不純物を二次イオン質量分析する際に、試
料表面にイオンビームスパッタでＰｔを蒸着した。イオ
ンビームスパッタのスパッタ条件は、イオン電流；６０
μＡ、加速電圧；５ｋＶ、スパッタ時間１０分間とし
た。(Example 1) S on a Si substrate, which is usually difficult to measure
When secondary ion mass spectrometry was performed for impurities in the iO 2 film, Pt was deposited on the sample surface by ion beam sputtering. The sputtering conditions for ion beam sputtering are: ion current; 60
μA, accelerating voltage; 5 kV, sputtering time 10 minutes.
【００１７】この結果、膜厚３０ÅのＰｔ膜が蒸着され
た。表面を高分解能走査型電子顕微鏡（ＦＥ−ＳＥＭ）
で観察したところ、Ｐｔの粒子径は３０Åであることが
分かった。この前処理を施した試料を用いてＳＩＭＳ測
定を行なった。測定条件は、一次イオンＯ2+，１０．５
ｋｅＶ、二次イオン１１Ｂ+とした。As a result, a Pt film having a film thickness of 30 Å was deposited. High resolution scanning electron microscope (FE-SEM) on the surface
As a result, it was found that the particle diameter of Pt was 30Å. SIMS measurement was carried out using the sample subjected to this pretreatment. The measurement conditions are primary ion O 2+ , 10.5
keV and secondary ion 11B + .
【００１８】この結果、従来、前処理なしでは測定不可
能であったＳｉＯ2膜中のデプスプロファイル（Depth P
rofile）を測定することが可能となった。また、従来の
イオンスパッタによるＡｕ蒸着の表面状態や抵抗加熱蒸
着によるＡｕＰｄ蒸着の表面状態に比べて蒸着粒子が均
一でかつ非常に小さいため、膜厚も小さくしかも一定で
あって再現性の向上が顕著であった。As a result, the depth profile in the SiO 2 film (Depth P
rofile) can be measured. Further, compared with the conventional Au vapor deposition surface state by ion sputtering and AuPd vapor deposition surface state by resistance heating vapor deposition, the deposition particles are uniform and very small, so the film thickness is small and constant, and reproducibility is improved. It was remarkable.
【００１９】（実施例２）試料表面に前処理として図１
のようなＰｄのパターニング膜を形成した。この際のＰ
ｄ超微粒子膜の形成は、有機Ｐｄ化合物を含む溶液をス
ピナーで塗布し、その後３００℃で２０分間焼成して行
なった。なお、パターニングは、通常良く用いられるリ
フトオフプロセスにて行なった。この結果、膜厚５０Å
のＰｄ膜が蒸着された。また、高分解能走査型電子顕微
鏡（ＦＥ−ＳＥＭ）観察により、Ｐｄは約３０Åの粒径
を有することがわかった。(Embodiment 2) As a pretreatment on the sample surface, FIG.
A Pd patterning film as described above was formed. P at this time
The d ultrafine particle film was formed by applying a solution containing an organic Pd compound with a spinner and then baking at 300 ° C. for 20 minutes. The patterning was performed by a lift-off process that is usually used. As a result, the film thickness is 50Å
Of Pd film was deposited. Further, it was found by observation with a high resolution scanning electron microscope (FE-SEM) that Pd had a particle size of about 30Å.
【００２０】このような前処理を行なった試料のＳＩＭ
Ｓ測定を行なった。測定条件は実施例１と同様である
が、測定したい領域の大きさによってパターニングされ
ていないＳｉＯ2の適切な表面部分を選択して測定を行
なった。SIM of a sample which has been subjected to such pretreatment
S measurement was performed. The measurement conditions were the same as in Example 1, but the measurement was performed by selecting an appropriate surface portion of SiO 2 which was not patterned depending on the size of the region to be measured.
【００２１】この方法では、測定目的に応じて測定領域
の大きさなどを変えたい場合、即座にパターニングによ
り蒸着物質（この場合はＰｄ）の影響のない、しかも伝
導性の最も良好な測定部位を選択することが可能とな
り、測定の効率アップにつながった。また、定量分析な
どを行なう際には、ＳＩＭＳ測定によるスパッタの深さ
のα−ステップ測定が必要となってくるが、この方法に
よれば、１基板の複数点のＳＩＭＳ測定を行なった場合
の測定部位の特定が容易に行なえるという長所もある。According to this method, when it is desired to change the size of the measurement region according to the purpose of measurement, patterning is immediately performed to determine the measurement site which is free from the influence of the deposition material (Pd in this case) and has the best conductivity. It became possible to select, which led to the improvement of measurement efficiency. Further, when performing quantitative analysis or the like, it is necessary to perform the α-step measurement of the sputtering depth by SIMS measurement. According to this method, the SIMS measurement at a plurality of points on one substrate is performed. There is also an advantage that the measurement site can be easily specified.
【００２２】[0022]
【発明の効果】以上説明したように、本発明の前処理を
施した測定法により、これまで測定が困難とされていた
絶縁物のＳＩＭＳ測定を、いかなる場合においても再現
性良く、しかも良好な効率で行なうことができる。As described above, the SIMS measurement of an insulator, which has been difficult to measure up to now, can be performed with good reproducibility in any case by using the pretreatment method of the present invention, and it is excellent. It can be done with efficiency.
【図１】Ｐｄのパターニング膜を試料のＳｉＯ2膜に形
成したものの模式図であり、ａは平面図、ｂは断面図で
ある。FIG. 1 is a schematic view of a Pd patterning film formed on a sample SiO 2 film, in which a is a plan view and b is a cross-sectional view.
１ 金属蒸着膜 ２ 無蒸着部（測定試料面） 1 metal deposition film 2 non-deposition part (measurement sample surface)
Claims (4)
し、該試料の表面から発生する二次イオンを引き出して
質量分析を行なうことにより該試料の定性・定量を行な
う絶縁物の二次イオン質量分析法において、測定前に絶
縁物試料の表面に導電性物質の超微粒子層を形成するこ
とを特徴とする絶縁物の二次イオン質量分析法。1. A secondary ion mass of an insulator for qualitatively / quantifying the sample by irradiating an insulator sample with a primary ion beam and extracting secondary ions generated from the surface of the sample for mass spectrometry. In the analysis method, a secondary ion mass spectrometric method for an insulating material, comprising forming an ultrafine particle layer of a conductive substance on the surface of an insulating material sample before measurement.
が０．００３μｍ以下である請求項１記載の質量分析
法。2. The mass spectrometric method according to claim 1, wherein the particle diameter of the electroconductive substance ultrafine particle layer to be formed is 0.003 μm or less.
タ法で行なう請求項１または２記載の質量分析法。3. The mass spectrometric method according to claim 1, wherein the ultrafine particle layer is formed by an ion beam sputtering method.
属溶液を塗布後に焼成することによって行なう請求項１
または２記載の質量分析法。4. The ultrafine particle layer is formed by applying an organic metal solution to the surface of the insulating material and then firing the applied solution.
Or the mass spectrometric method described in 2.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5146174A JPH0720021A (en) | 1993-06-17 | 1993-06-17 | Secondary ion-mass spectrometry for insulator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5146174A JPH0720021A (en) | 1993-06-17 | 1993-06-17 | Secondary ion-mass spectrometry for insulator |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0720021A true JPH0720021A (en) | 1995-01-24 |
Family
ID=15401815
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5146174A Pending JPH0720021A (en) | 1993-06-17 | 1993-06-17 | Secondary ion-mass spectrometry for insulator |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0720021A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6312046B1 (en) | 1998-12-09 | 2001-11-06 | Yazaki Corporation | Grommet and fixing structure thereof |
| US6376768B1 (en) | 1999-10-29 | 2002-04-23 | Yazaki Corporation | Wire guiding out structure of wire protector |
| JP2008051639A (en) * | 2006-08-24 | 2008-03-06 | Ulvac Japan Ltd | Secondary ion mass analysis method for insulating material |
-
1993
- 1993-06-17 JP JP5146174A patent/JPH0720021A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6312046B1 (en) | 1998-12-09 | 2001-11-06 | Yazaki Corporation | Grommet and fixing structure thereof |
| US6431642B2 (en) | 1998-12-09 | 2002-08-13 | Yazaki Corporation | Grommet and fixing structure thereof |
| US6376768B1 (en) | 1999-10-29 | 2002-04-23 | Yazaki Corporation | Wire guiding out structure of wire protector |
| JP2008051639A (en) * | 2006-08-24 | 2008-03-06 | Ulvac Japan Ltd | Secondary ion mass analysis method for insulating material |
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