JP6892198B2 - Joining method of magnesium fluoride crystals - Google Patents

Joining method of magnesium fluoride crystals Download PDF

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JP6892198B2
JP6892198B2 JP2017026513A JP2017026513A JP6892198B2 JP 6892198 B2 JP6892198 B2 JP 6892198B2 JP 2017026513 A JP2017026513 A JP 2017026513A JP 2017026513 A JP2017026513 A JP 2017026513A JP 6892198 B2 JP6892198 B2 JP 6892198B2
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magnesium fluoride
crystal pieces
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篤 深澤
篤 深澤
智 早田
智 早田
佐藤 和幸
和幸 佐藤
公則 大村
公則 大村
弘 河西
弘 河西
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株式会社 ジャパンセル
株式会社 ジャパンセル
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Priority to EP17763290.8A priority patent/EP3428326B1/en
Priority to PCT/JP2017/009149 priority patent/WO2017154950A1/en
Priority to US15/767,497 priority patent/US10519567B2/en
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Description

本発明は、超低屈折光学材料として知られるフッ化マグネシウム(MgF2)結晶体の接合方法に関する。 The present invention relates to a method for joining magnesium fluoride (MgF 2 ) crystals known as an ultra-low refraction optical material.

パーティクルカウンターなどに組み込む合成コランダム製のフローセルを製造するには、板状の合成コランダム片を複数用意し、これら合成コランダム片を接合することで得ている。ここで、接着剤を用いたのでは接合面において境界面ができてしまい、光が屈折したり反射してしまう。また、熱融着させた場合には、接合面に気泡が封じ込められるなどの問題もある。 In order to manufacture a flow cell made of synthetic corundum to be incorporated into a particle counter or the like, a plurality of plate-shaped synthetic corundum pieces are prepared and these synthetic corundum pieces are joined. Here, if an adhesive is used, a boundary surface is formed at the joint surface, and light is refracted or reflected. Further, when heat-sealed, there is a problem that air bubbles are contained in the joint surface.

そこで、本出願人は特許文献1〜3を提案した。特許文献1〜3に開示される接合方法は基本的には同じであり、先ず結晶ブロックから合成コランダム片を切り出し、この切り出した合成コランダム片の接合面を研磨し、研磨した面同士を合わせ、合わせた状態の2枚の合成コランダム片の一端部側を強く押し付け、2枚の合成コランダム片の間隔を干渉縞ができる程度とし、この状態で2枚の合成コランダム片を合成コランダムの融点(2030℃)以下に加熱することで、一端側から他端側に向かって徐々に密着状態となるようにしたものである。 Therefore, the applicant has proposed Patent Documents 1 to 3. The joining methods disclosed in Patent Documents 1 to 3 are basically the same. First, a synthetic corundum piece is cut out from a crystal block, the joint surface of the cut out synthetic corundum piece is polished, and the polished surfaces are combined. The one end side of the two synthetic corundum pieces in the combined state is strongly pressed, and the distance between the two synthetic corundum pieces is set to the extent that interference fringes are formed. In this state, the two synthetic corundum pieces are placed at the melting point of the synthetic corundum (2030). By heating to ℃) or less, the state of close contact gradually increases from one end side to the other end side.

上記において、強く押し付けた状態の一端部側ではオプティカルコンタクト状態或いは化学的加圧密着状態になっており、加熱によって干渉縞がなくなるので、この密着状態が他端側まで連続すると考えられる。そして、このように接合された合成コランダム片同士は光学的な境界面が存在せず、極めて優れた三次元構造体が得られる。
In the above, the one end side in the strongly pressed state is in the optical contact state or the chemically pressurized contact state, and the interference fringes disappear by heating, so it is considered that this contact state continues to the other end side. Then, the synthetic corundum pieces joined in this way do not have an optical boundary surface, and an extremely excellent three-dimensional structure can be obtained.

特許第3499717号公報Japanese Patent No. 3499717 特許第4224336号公報Japanese Patent No. 4224336 特許第4251462号公報Japanese Patent No. 4251462

特許文献1〜3に開示される方法によって製造された接合体は、耐薬品性に優れ、接合面が剥離したり接合面で屈折或いは反射する等の不具合がない反面、歩留りが十分ではないという問題がある。 The joints produced by the methods disclosed in Patent Documents 1 to 3 have excellent chemical resistance and do not have problems such as peeling of the joint surface and refraction or reflection at the joint surface, but the yield is not sufficient. There's a problem.

歩留りが十分ではない原因としては、一端部側を他端側よりも強く押し付けることで、接合面同士の間に干渉縞ができる程度の隙間を形成するようにしているが、他端側は何ら拘束していないため、他端側における合成コランダム片同士の間に形成される微細な隙間が一定でないことが考えられる。
この問題は、フッ化マグネシウム(MgF2)結晶体を接合する場合にも生じる。
The reason why the yield is not sufficient is that the one end side is pressed harder than the other end side to form a gap between the joint surfaces to the extent that interference fringes are formed. Since it is not constrained, it is conceivable that the minute gaps formed between the synthetic corundum pieces on the other end side are not constant.
This problem also occurs when joining magnesium fluoride (MgF 2) crystals.

上記課題を解決するため、本発明に係るフッ化マグネシウム(MgF2)結晶体片の接合方法は、互いに接合するフッ化マグネシウム結晶体片の接合する面を合わせ、この合わせた状態の結晶体片の一端側を他端側よりも強く押圧して合わせ面に干渉縞を形成し、この状態で結晶体片を結晶体の融点以下の温度で加熱することで、前記合わせ面を干渉縞が消失した完全な接合状態とする接合方法であって、前記互いに接合する結晶体片の他端側間に加熱時の圧力で圧潰可能な材質からなる微細なスペーサを介在させるようにした。 In order to solve the above problems, the method for joining magnesium fluoride (MgF 2 ) crystal pieces according to the present invention is to align the bonding surfaces of magnesium fluoride crystal pieces to be bonded to each other, and the crystal pieces in this combined state. By pressing one end side more strongly than the other end side to form interference fringes on the mating surface and heating the crystal piece at a temperature equal to or lower than the melting point of the crystal in this state, the interference fringes disappear on the mating surface. In this joining method, a fine spacer made of a material that can be crushed by the pressure at the time of heating is interposed between the other ends of the crystal pieces to be joined to each other.

前記スペーサとしては、熱処理によって干渉縞が消失するのを妨げることがないもの、つまり接合する結晶体片同士がオプティカルコンタクト或いは化学的加圧密着状態となることを妨げない程度の圧潰性(弾性、柔らかさ)を有することが必要である。 The spacer is one that does not prevent the interference fringes from disappearing due to heat treatment, that is, crushability (elasticity,) that does not prevent the bonded crystal pieces from being in optical contact or chemical consolidation. It is necessary to have softness).

スペーサの一例としては綿繊維が挙げられるが、これに限定されるものではない。またスペーサの大きさは必要な干渉縞を形成するものであるから、合成コランダム片の接合長さによって異なるが、概ね15〜60μmの径である。 An example of a spacer is, but is not limited to, cotton fiber. Further, since the size of the spacer forms the necessary interference fringes, the diameter varies depending on the joining length of the synthetic corundum piece, but is approximately 15 to 60 μm.

また、本発明に係る接合方法においては、接合する結晶体片の一端側を押圧した仮接合の状態で、合わせた状態の結晶体片の単位長さ当たりの縞の本数によって、加熱処理前に仮接合状態の良否を判断することができる。 Further, in the joining method according to the present invention, in the state of temporary joining in which one end side of the crystal pieces to be joined is pressed, the number of stripes per unit length of the combined crystal pieces is determined before the heat treatment. It is possible to judge whether the temporary joining state is good or bad.

また、合わせた状態の結晶体片の一端部の押圧箇所は幅方向の一部のみとすることも可能である。 Further, it is also possible that the pressing portion of one end of the combined crystal pieces is only a part in the width direction.

本発明によれば、結晶体片同士を接着剤を用いずに、一端側を他端側よりも強く押圧した状態での熱処理によって接合するに際し、他端側の結晶体片間の間隔をスペーサによって正確にコントロールできるため、歩留りを高めることができる。 According to the present invention, when the crystal pieces are joined by heat treatment in a state where one end side is pressed more strongly than the other end side without using an adhesive, the space between the crystal pieces on the other end side is spacerd. Because it can be controlled accurately by, the yield can be increased.

また、熱処理する前の仮接合の状態で、接合される結晶体片の接合面間に形成される干渉縞の単位長さあたりの本数によって、仮接合の状態の良否を判定できるため、更に歩留りを高めることができる。 Further, in the temporary bonding state before the heat treatment, the quality of the temporary bonding state can be determined by the number of interference fringes formed between the bonding surfaces of the crystal pieces to be bonded per unit length, so that the yield is further increased. Can be enhanced.

更に、合わせた状態の結晶体片の一端部の押圧箇所を幅方向全部ではなく幅方向の一部のみとすることで、押圧治具の跡が付く箇所が一部のみになり、接合後の不適合部分が少なくなり、材料の無駄がなくなる。 Further, by limiting the pressing portion of one end of the combined crystal pieces to only a part in the width direction instead of the entire width direction, only a part of the pressing jig has a mark after joining. There are fewer non-conforming parts and there is no waste of material.

2つのフッ化マグネシウム(MgF2)結晶体片を重ね合わせた状態の側面図 Side view of two magnesium fluoride (MgF 2) crystal pieces stacked 一方のフッ化マグネシウム(MgF2)結晶体片の端部にスペーサを載置した状態の平面図Top view of a state in which a spacer is placed on the end of one magnesium fluoride (MgF 2) crystal piece. 2つのフッ化マグネシウム(MgF2)結晶体片を重ね合わせた際に生じる干渉縞の写真Photograph of interference fringes generated when two magnesium fluoride (MgF 2) crystal pieces are overlapped (a)は3つのフッ化マグネシウム結晶体を同時に接合した構造体の正面の写真、(b)は同構造体の背面の写真(A) is a photograph of the front of a structure in which three magnesium fluoride crystals are simultaneously bonded, and (b) is a photograph of the back of the structure.

以下に本発明の実施の形態を添付図面に基づいて説明する。図1は2つのフッ化マグネシウム結晶体片を重ね合わせた状態の側面図、図2は一方のフッ化マグネシウム結晶体片の端部にスペーサを載置した状態の平面図であり、先ず2つのフッ化マグネシウム結晶体片1、2を用意する。 Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a side view of two magnesium fluoride crystal pieces stacked on top of each other, and FIG. 2 is a plan view of a state in which a spacer is placed on the end of one magnesium fluoride crystal piece. Prepare magnesium fluoride crystal pieces 1 and 2.

これらフッ化マグネシウム結晶体片1、2は結晶ブロックから切り出した後に、接合される面を研磨した後に洗浄し、微細なゴミなどが接合面にないことを確認したものである。尚、図示例では2つのフッ化マグネシウム結晶体片を重ねているが3つ以上の合成コランダム片を重ねて同時に接合することもできる。 These magnesium fluoride crystal pieces 1 and 2 were cut out from the crystal block, and then the surface to be bonded was polished and then washed, and it was confirmed that there was no fine dust or the like on the bonded surface. In the illustrated example, two magnesium fluoride crystal pieces are overlapped, but three or more synthetic corundum pieces can be overlapped and bonded at the same time.

フッ化マグネシウム結晶体片1、2を重ねる際には結晶の軸、稜線及び軸角を完全に一致させる必要はなく、互いのフッ化マグネシウム結晶体片1、2の結晶の軸、稜線及び軸角のズレが5°以内とするのが好ましい。 When stacking magnesium fluoride crystal pieces 1 and 2, it is not necessary to completely match the axis, ridgeline and axis angle of the crystal, and the axis, ridgeline and axis of the crystals of magnesium fluoride crystal pieces 1 and 2 are not exactly the same. It is preferable that the angle deviation is within 5 °.

フッ化マグネシウム結晶体片1、2の一端側は治具4によって強く押圧或いは挟持されている。治具4による押圧箇所は幅方向の全域としてもよいが図示例のように幅方向の中央の一部のみとすることで、接合後の不適合部分を少なくしている。 One end side of the magnesium fluoride crystal pieces 1 and 2 is strongly pressed or sandwiched by the jig 4. The pressed portion by the jig 4 may be the entire area in the width direction, but as shown in the illustrated example, only a part of the center in the width direction is used to reduce the non-conforming portion after joining.

フッ化マグネシウム結晶体片1、2の他端側の接合面間にはスペーサ3が介在している。このスペーサ3は図では分かりやすくするため実際よりは大きく示しているが、実施例では直径が30μmの綿繊維を用いている。スペーサ3は、仮接合後の熱処理の際にフッ化マグネシウム結晶体片1、2の他端側に作用する圧力によって潰れることで、フッ化マグネシウム結晶体片1、2の他端側でのオプティカルコンタクト或いは化学的加圧密着状態の妨げにならないものであればよい。 A spacer 3 is interposed between the bonding surfaces on the other ends of the magnesium fluoride crystal pieces 1 and 2. The spacer 3 is shown larger than it actually is for the sake of clarity in the figure, but in the examples, cotton fibers having a diameter of 30 μm are used. The spacer 3 is crushed by the pressure acting on the other end side of the magnesium fluoride crystal pieces 1 and 2 during the heat treatment after the temporary bonding, so that the spacer 3 is optical on the other end side of the magnesium fluoride crystal pieces 1 and 2. Anything that does not interfere with the contact or the chemical pressure adhesion state may be used.

スペーサ3としては、ゲルビーズなども使用することができるが、仮接合後の熱処理の際に大量にガスを発生するものは、接合面に気泡が残る可能性があるので好ましくない。 Gel beads or the like can also be used as the spacer 3, but those that generate a large amount of gas during the heat treatment after the temporary bonding are not preferable because bubbles may remain on the bonding surface.

図3は重ね合わせたフッ化マグネシウム結晶体片1、2の一端部を押圧した状態の平面写真であり、この写真からも明らかなように、重ね合わせたフッ化マグネシウム結晶体片1、2の接合面の微細な隙間に由来する干渉縞が観察される。 FIG. 3 is a plan photograph of the stacked magnesium fluoride crystal pieces 1 and 2 in a state where one end thereof is pressed, and as is clear from this photograph, the stacked magnesium fluoride crystal pieces 1 and 2 Interference fringes derived from minute gaps on the joint surface are observed.

上記干渉縞の間隔は接合面の微細な隙間の大きさに比例するため、仮接合状態での単位長さあたりの干渉縞の本数をカウントすることにより、フッ化マグネシウム結晶体片1、2の接合面の微細な隙間が適切な範囲にあるか否かを、前もって判断することができる。この実施例にあっては単位長さあたりに5本の縞が観察される。 Since the interval between the interference fringes is proportional to the size of the fine gaps on the bonding surface, the number of interference fringes per unit length in the temporary bonding state is counted to obtain the magnesium fluoride crystal pieces 1 and 2. Whether or not the fine gaps on the joint surface are within an appropriate range can be determined in advance. In this embodiment, five stripes are observed per unit length.

以上の仮接合状態のフッ化マグネシウム結晶体片をフッ化マグネシウムの融点以下の温度まで加熱し一定時間保持する。
すると、既にオプティカルコンタクト或いは化学的加圧密着状態にある一端側から他端側に向かってオプティカルコンタクト或いは化学的加圧密着状態が進行し、この進行に併せて、フッ化マグネシウム結晶体片間に存在するガスは完全に排除され、接合面全体がオプティカルコンタクト或いは化学的加圧密着状態となる。
The magnesium fluoride crystal piece in the above temporarily bonded state is heated to a temperature below the melting point of magnesium fluoride and held for a certain period of time.
Then, the optical contact or the chemical pressure consolidation state progresses from one end side to the other end side which is already in the optical contact or the chemical pressure consolidation state, and along with this progress, between the magnesium fluoride crystal pieces. The existing gas is completely eliminated, and the entire joint surface becomes optical contact or chemical consolidation.

図4(a)は3つのフッ化マグネシウム結晶体を同時に接合した構造体の正面の写真、(b)は同構造体の背面の写真であり、これらの写真から接合後には上記の干渉縞が全く観察されず、光学的な境界面が認められないことが分かる。 FIG. 4A is a photograph of the front surface of a structure in which three magnesium fluoride crystals are bonded at the same time, and FIG. 4B is a photograph of the back surface of the structure. It is not observed at all, and it can be seen that no optical interface is observed.

実施例ではフッ化マグネシウム結晶体片同士を接合した例を示したが、本発明方法はフッ化マグネシウム結晶体と合成コランダム片、或いはフッ化マグネシウム結晶体とフッ化カルシウム結晶体片との接合にも応用することができる。 In the examples, examples of joining magnesium fluoride crystal pieces to each other were shown, but the method of the present invention is used for joining magnesium fluoride crystals and synthetic corundum pieces, or magnesium fluoride crystals and calcium fluoride crystal pieces. Can also be applied.

本発明方法は微粒子計に組み込まれるフローセルに限らず、レンズ、プリズムなどの各種光学部品、硬度が要求される機械部品、接合面が密閉状態にある特性を利用した真空容器、例えば可変波長レーザの較正、光スペクトラムアナライザの較正、ガス分析器の較正、波長計の較正、周波数標準、安定した周波数源、磁気光学トラップ法を用いた原子のレーザ冷却などに用いられるガス封入ガラスセルや高真空ガラスチャンバなどに応用することができる。 The method of the present invention is not limited to the flow cell incorporated in the fine particle meter, but is used for various optical parts such as lenses and prisms, mechanical parts requiring hardness, and vacuum containers utilizing the characteristic that the joint surface is sealed, for example, a variable frequency laser. Gas-filled glass cells and high vacuum glass used for calibration, optical spectrum analyzer calibration, gas analyzer calibration, wavelength meter calibration, frequency standard, stable frequency source, laser cooling of atoms using magnetic optical trap method, etc. It can be applied to chambers and the like.

1、2…フッ化マグネシウム結晶体片、3…スペーサ、4…押圧治具。
1, 2 ... Magnesium fluoride crystal piece, 3 ... Spacer, 4 ... Pressing jig.

Claims (3)

互いに接合するフッ化マグネシウム結晶体片の接合する面を合わせ、合わせた状態のフッ化マグネシウム結晶体片の一端側を他端側よりも強く押圧し、合わせ面に干渉縞を形成し、この状態でフッ化マグネシウム結晶体を結晶体の融点以下の温度で加熱することで、前記合わせ面を干渉縞が消失した完全な接合状態とする結晶体片の接合方法において、前記互いに接合する結晶体片の他端側の合わせ面間に加熱時の圧力で圧潰可能な材質からなる微細なスペーサを介在させることを特徴とするフッ化マグネシウム結晶体片の接合方法。 The surfaces of the magnesium fluoride crystal pieces to be bonded to each other are aligned, and one end side of the combined magnesium fluoride crystal pieces is pressed more strongly than the other end side to form interference fringes on the combined surfaces. In the method of joining crystal pieces, in which the magnesium fluoride crystals are heated at a temperature equal to or lower than the melting point of the crystals to bring the mating surfaces into a completely bonded state in which interference fringes have disappeared, the crystal pieces bonded to each other. A method for joining magnesium fluoride crystal pieces, which comprises interposing a fine spacer made of a material that can be crushed by the pressure at the time of heating between the mating surfaces on the other end side. 請求項1に記載の結晶体片の接合方法において、前記スペーサは径が15〜60μmの綿とすることを特徴とするフッ化マグネシウム結晶体片の接合方法。 The method for joining a magnesium fluoride crystal piece according to claim 1, wherein the spacer is made of cotton having a diameter of 15 to 60 μm. 請求項1に記載の結晶体片の接合方法において、合わせた状態の結晶体片の一端部の押圧箇所は幅方向の一部のみとすることを特徴とするフッ化マグネシウム結晶体片の接合方法。 The method for joining a magnesium fluoride crystal piece according to claim 1, wherein the pressed portion of one end of the combined crystal pieces is only a part in the width direction. ..
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JP2017026513A JP6892198B2 (en) 2017-02-16 2017-02-16 Joining method of magnesium fluoride crystals
EP17763290.8A EP3428326B1 (en) 2016-03-08 2017-03-08 Method for joining crystal body
PCT/JP2017/009149 WO2017154950A1 (en) 2016-03-08 2017-03-08 Method for joining crystal body
US15/767,497 US10519567B2 (en) 2016-03-08 2017-03-08 Bonding method of crystal body

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