JPWO2005003736A1

JPWO2005003736A1 - Thin sample preparation method and composite charged particle beam apparatus

Info

Publication number: JPWO2005003736A1
Application number: JP2005511434A
Authority: JP
Inventors: 藤井　利昭; 利昭藤井
Original assignee: SII NanoTechnology Inc
Current assignee: Hitachi High Tech Science Corp
Priority date: 2003-07-08
Filing date: 2004-07-05
Publication date: 2006-08-17

Abstract

集束イオンビーム３１２のスパッタリングエッチング加工を行って薄片を作製すると同時に、薄片の側壁に対して平行な方向から電子ビーム３１４の照射を行って走査電子顕微鏡観察をし、薄片の厚さを測定する。そして、薄片の厚さが所定の厚さになったことを確認して、集束イオンビーム３１２による加工を終了する。A thin piece is produced by performing the sputtering etching process of the focused ion beam 312. At the same time, the electron beam 314 is irradiated from a direction parallel to the side wall of the thin piece, and observation with a scanning electron microscope is performed to measure the thickness of the thin piece. Then, after confirming that the thickness of the thin piece has reached a predetermined thickness, the processing by the focused ion beam 312 is finished.

Description

透過電子顕微鏡などの高分解能顕微鏡にて半導体デバイスや表示デバイス等の内部構造を観察するために、その試料として半導体デバイスや表示デバイスから薄片試料を作製する方法に関するものである。 The present invention relates to a method for producing a thin sample from a semiconductor device or a display device as a sample for observing the internal structure of a semiconductor device, a display device or the like with a high-resolution microscope such as a transmission electron microscope.

集束イオンビーム照射系と電子ビーム照射系とからなる複合装置を用いて、集束イオンビームにて試料表面の所望箇所をスパッタリングエッチング加工して薄片試料を作製し、作製した薄片試料を取り出し、取り出した薄片試料を透過電子顕微鏡にて観察する方法が知られている（例えば、特許文献１参照）。
特開平４−７６４３７号公報特開平４−６２７４８号公報近年、半導体デバイスや表示デバイスなどの各種デバイスは、機能向上を実現するため、その構造は微細に、そして複雑になっている。特に、各デバイスを形成する素子や配線が数原子層レベルの薄膜を重ねた積層構造になっており、その構造を観察する需要は高い。この微細構造を観察するため透過電子顕微鏡を利用する。微細構造を高分解能顕微鏡観察するためには観察のための薄片試料作製を行う。この際に、集束イオンビームによるエッチング加工を行った際に薄片試料に残る損傷を最小限にすると同時に、薄片試料の形状確認を電子ビーム照射走査による走査電子顕微鏡観察にて行なうことが知られている。
薄片試料の厚さを均一にするために、試料を傾斜しながら加工することが知られている（例えば、特許文献２参照）。しかしながら、このような加工方法において、薄片の厚さを制御する方法は知られていない。
本発明は、上記問題点を解決し、試料表面の所望の箇所に薄片を形成する際に、薄片の厚さを正確に制御することによって、高分解能顕微鏡観察が容易な試料作製を行なうことにより、各種デバイスの発展に寄与することを目的になされている。Using a combined device consisting of a focused ion beam irradiation system and an electron beam irradiation system, a thin sample is prepared by sputtering etching the desired portion of the sample surface with a focused ion beam, and the prepared thin sample is taken out and taken out. A method of observing a thin sample with a transmission electron microscope is known (for example, see Patent Document 1).
JP-A-4-76437 JP-A-4-62748 In recent years, various devices such as semiconductor devices and display devices have become finer and more complicated in order to realize functional improvements. In particular, the elements and wirings forming each device have a laminated structure in which thin films of several atomic layers are stacked, and the demand for observing the structure is high. A transmission electron microscope is used to observe this fine structure. In order to observe the fine structure with a high-resolution microscope, a thin sample is prepared for observation. At this time, it is known to minimize the damage left on the thin sample when etching with a focused ion beam, and at the same time, confirm the shape of the thin sample by scanning electron microscope observation by electron beam irradiation scanning. Yes.
In order to make the thickness of a thin sample uniform, it is known that the sample is processed while being inclined (see, for example, Patent Document 2). However, in such a processing method, a method for controlling the thickness of the flake is not known.
The present invention solves the above-mentioned problems, and by forming a thin piece at a desired location on the sample surface, by accurately controlling the thickness of the thin piece, it is possible to prepare a sample that can be easily observed with a high-resolution microscope. The goal is to contribute to the development of various devices.

上記課題を解決するために、本願発明においては、集束イオンビームを用いて試料表面上方より集束イオンビームを照射して試料表面をエッチング加工し薄片試料を形成する方法において、形成した薄片部の側壁に対して平行な方向から電子ビームを走査照射して、薄片部の厚さを測定するものである。また、その厚みを確認しながら薄片部を形成するようにしたものである。
また、ＦＩＢ−ＳＥＭ複合ビーム装置を用い、そのステージのチルト方向を、試料ステージ面が各ビーム鏡筒を含む平面となす角度が変更可能な方向にした。このことを図４を用いて説明する。
通常は、図４（ａ）のように試料ステージ４０７は各ビーム鏡筒４０１、４０３を含む平面方向に傾斜するように構成されている。
それに対して、本発明においてはさらに、図４（ｂ）に示すように少なくとも９０度異なる軸に対して傾斜する構成を有する。このことにより集束イオンビームで側壁の傾斜角を補正して加工できると同時に、あるいはすぐさま電子ビームで薄片試料の厚みを測定することができる。あるいは、さらに上記両方向に傾斜することも含む。すなわち、ＦＩＢ−ＳＥＭ複合ビーム装置において、傾斜軸を２つ持つデュアルチルト構成となっている。
すなわち、本願発明薄片試料作製方法においては、まず第一に、試料表面に集束イオンビームを走査照射してエッチング加工することにより薄片部を形成し、該薄片部を取り出すことにより、薄片試料を作製する方法において、集束イオンビームのエッチング加工によって、薄片部を作製すると同時にまたは前記集束イオンビームの照射を一時中断して、前記作製された薄片部の側壁に対して平行な方向から電子ビームを走査照射して前記薄片の表面部分を顕微鏡観察し、前記薄片部の厚さを測定することを特徴とする。
第二に、前記薄片の厚さが所定の厚さになったことを確認してエッチング加工を終了することを特徴とする。
第三に、試料表面に集束イオンビームを走査照射してエッチング加工することにより薄片部を形成し、該薄片部を取り出すことにより、薄片試料を作製する方法において、集束イオンビームを用いて第一の集束イオンビーム条件で薄片とすべき領域の両側をエッチング加工する第一の工程と、前記第一の工程に続いて前記集束イオンビームを用いて前記第一の集束イオンビーム条件と比較して低加速電圧かつ／または低ビーム電流である第二の集束イオンビーム条件で薄片とすべき領域の第１の側壁あるいはその反対側の第２の側壁をエッチング加工するのと同時に、前記薄片とすべき領域の側壁に対して平行な方向から電子ビームを走査照射して前記薄片とすべき領域の表面部分を顕微鏡観察し、前記薄片とすべき領域の厚さを測定する第二の工程とからなることを特徴とする。
第四に、前記薄片とすべき領域の第一の側壁に対し前記第二の工程を施し、第一の所望の厚さに形成にした後、前記薄片とすべき領域の第二の側壁に対して前記第二の工程を施して、前記所定の厚さに形成することを特徴とする。
第五に、前記第二の工程において、前記薄片とすべき領域の側壁をエッチング加工する時に、前記集束イオンビームが該側壁にその傾斜を補正するように照射されるように前記試料を傾斜させることを特徴とする。
第六に、試料表面に集束イオンビームを走査照射してエッチング加工することにより薄片部を形成し、該薄片部を取り出すことにより、薄片試料を作製する方法において、集束イオンビームを用いて薄片とすべき領域の両側をエッチング加工して薄片部を作製する第一の工程と、前記薄片の第一の側壁にその傾斜を補正するように集束イオンビームが照射されるように前記試料を傾斜させて、集束イオンビームを走査照射してエッチングを行うのと同時に前記薄片部の側壁に概ね平行に電子ビームを走査照射して前記薄片部の表面部分を顕微鏡観察し、前記薄片部の厚さが第一の所定の厚さになることを確認してエッチング加工を終了する第二の工程と、前記薄片部の第二の側壁にその傾斜を補正するように集束イオンビームが照射されるように前記試料を傾斜させて、前記集束イオンビームを走査照射してエッチングを行うのと同時に前記薄片の側壁に概ね平行に電子ビームを走査照射して前記薄片部の表面部分を顕微鏡観察し、前記薄片部の厚さが第二の所定の厚さになることを確認してエッチングを終了する第三の工程と、前記第三の工程に続いて不活性イオンビームを照射して前記薄片部の両側をスパッタリングエッチング加工するのと同時に、前記薄片部の側壁に対して平行な方向から電子ビームを走査照射して前記薄片の表面部分を顕微鏡観察し、前記薄片部の厚さを測定し、前記薄片部の厚さが第三の所定の厚さになることを確認して前記不活性イオンビームによるスパッタリングエッチング加工を終了する第四の工程と、を含むことを特徴とする。
また本願発明における荷電粒子ビーム装置においては、イオン源から発生したイオンビームを集束して試料表面に走査照射する集束イオンビーム鏡筒と、電子源から発生した電子ビームを集束して試料表面に走査照射する電子ビーム鏡筒と、試料を載置して複数の駆動軸を持って三次元空間を移動させる試料ステージからなる集束イオンビーム及び電子ビーム複合装置において、両ビーム鏡筒は、前記集束イオンビーム鏡筒より照射された集束イオンビームと、前記電子ビーム鏡筒より照射された電子ビームとが前記試料ステージ上に載置された試斜表面の同一箇所に異なる角度で照射されるように配置され、前記試料ステージは、少なくとも前記集束イオンビーム鏡筒中心軸と電子ビーム鏡筒中心軸によって形成される第一の平面に対して直角に交差する第二の平面を基準として前記第一の平面に対する角度を変更可能に傾斜することを特徴とする。
さらに、本願発明における荷電粒子ビーム装置においては、イオン源から発生したイオンビームを集束して試料表面に走査照射する集束イオンビーム鏡筒と、電子源から発生した電子ビームを集束して試料表面に走査照射する電子ビーム鏡筒と、不活性イオン源から発生した不活性イオンビームを集束して試料表面に走査照射する不活性イオンビーム鏡筒と、試料を載置して複数の駆動軸を持って三次元空間を移動させる試料ステージからなる集束イオンビーム及び電子ビーム複合装置において、前記集束イオンビーム鏡筒より照射された集束イオンビーム、前記電子ビーム鏡筒より照射された電子ビーム、そして前記不活性イオンビーム鏡筒より照射された不活性イオンビームとが、前記試料ステージ上に載置された試料表面の同一箇所に異なる角度で照射されるように配置されていることを特徴とする。In order to solve the above problems, in the present invention, in the method of forming a thin sample by etching the sample surface by irradiating the focused ion beam from above the sample surface using the focused ion beam, the side wall of the formed thin piece portion is used. The thickness of the thin piece portion is measured by scanning and irradiating an electron beam from a direction parallel to the surface. Further, the thin piece portion is formed while checking the thickness.
Further, the FIB-SEM composite beam apparatus was used, and the tilt direction of the stage was set to a direction in which the angle between the sample stage surface and the plane including each beam column could be changed. This will be described with reference to FIG.
Usually, as shown in FIG. 4A, the sample stage 407 is configured to incline in the plane direction including the beam barrels 401 and 403.
On the other hand, in the present invention, as shown in FIG. 4 (b), it has a configuration that is inclined with respect to an axis different by at least 90 degrees. As a result, processing can be performed while correcting the tilt angle of the side wall with a focused ion beam, or at the same time, the thickness of a thin sample can be measured with an electron beam. Alternatively, it may further include tilting in both directions. That is, the FIB-SEM composite beam apparatus has a dual tilt configuration having two tilt axes.
That is, in the thin sample preparation method of the present invention, first of all, a thin piece portion is formed by scanning and irradiating a focused ion beam to the sample surface to form a thin piece portion, and taking out the thin piece portion, thereby producing a thin piece sample. In this method, the electron beam is scanned from a direction parallel to the side wall of the produced thin piece part simultaneously with the production of the thin piece part by etching of the focused ion beam or by temporarily suspending the irradiation of the focused ion beam. Irradiation is performed to observe the surface portion of the thin piece under a microscope, and the thickness of the thin piece portion is measured.
Secondly, the etching process is terminated after confirming that the thickness of the thin piece has reached a predetermined thickness.
Thirdly, in the method for producing a thin piece sample by forming a thin piece portion by scanning and irradiating the sample surface with a focused ion beam and performing etching processing, a first method using a focused ion beam is performed. A first step of etching both sides of the region to be sliced under the focused ion beam condition of the first, and using the focused ion beam following the first step, compared with the first focused ion beam condition At the same time as etching the first side wall or the second side wall on the opposite side of the region to be sliced under a second focused ion beam condition with a low acceleration voltage and / or a low beam current, the slice is formed. Scanning and irradiating an electron beam from a direction parallel to the side wall of the power region, observing a surface portion of the region to be the thin piece under a microscope, and measuring the thickness of the region to be the thin piece Characterized in that comprising the steps.
Fourth, after the second step is performed on the first side wall of the region to be the flakes to form the first desired thickness, the second side wall of the region to be the flakes is formed. On the other hand, the second step is performed to form the predetermined thickness.
Fifth, in the second step, when the sidewall of the region to be thinned is etched, the sample is tilted so that the focused ion beam is irradiated to the sidewall to correct the tilt. It is characterized by that.
Sixth, in the method for producing a thin piece sample by forming a thin piece portion by scanning and irradiating the sample surface with a focused ion beam and performing etching, the thin piece portion is formed using the focused ion beam. A first step of etching the both sides of the region to be fabricated to produce a flake portion, and tilting the sample so that a focused ion beam is irradiated on the first side wall of the flake to correct the tilt Then, while performing etching by scanning irradiation with a focused ion beam, simultaneously scanning and irradiating an electron beam substantially parallel to the side wall of the thin piece portion, the surface portion of the thin piece portion is observed with a microscope, and the thickness of the thin piece portion is determined. A second step of confirming that the first predetermined thickness is reached and ending the etching process and a focused ion beam is applied to the second side wall of the thin piece portion so as to correct the inclination. The sample is tilted, and the focused ion beam is scanned and irradiated to perform etching. At the same time, an electron beam is scanned and irradiated in parallel with the side wall of the thin piece, and the surface portion of the thin piece portion is observed with a microscope. A third step of confirming that the thickness of the flake portion becomes the second predetermined thickness and ending the etching, and irradiating an inert ion beam following the third step to irradiate the flake portion. Simultaneously performing sputtering etching on both sides, scanning the electron beam from a direction parallel to the side wall of the thin piece portion, observing the surface portion of the thin piece with a microscope, measuring the thickness of the thin piece portion, And a fourth step of confirming that the thickness of the flake portion is the third predetermined thickness and terminating the sputtering etching process using the inert ion beam.
In the charged particle beam apparatus according to the present invention, the focused ion beam column for focusing and irradiating the sample surface with the ion beam generated from the ion source and the electron beam generated from the electron source are focused and scanned on the sample surface. In a focused ion beam and electron beam composite apparatus comprising an electron beam column to be irradiated and a sample stage on which a sample is mounted and has a plurality of drive shafts to move in a three-dimensional space, both beam column are the focused ions Arranged so that the focused ion beam irradiated from the beam column and the electron beam irradiated from the electron beam column are irradiated at different angles to the same spot on the sample oblique surface placed on the sample stage The sample stage is at least with respect to a first plane formed by the central axis of the focused ion beam column and the central axis of the electron beam column Characterized by tilting the second plane intersecting the corner angle relative to the first plane can be changed as a criterion.
Furthermore, in the charged particle beam apparatus according to the present invention, a focused ion beam column for focusing the ion beam generated from the ion source and scanning and irradiating the sample surface, and focusing the electron beam generated from the electron source on the sample surface. An electron beam column for scanning irradiation, an inert ion beam column for focusing an inert ion beam generated from an inert ion source and scanning and irradiating the sample surface, and a plurality of drive shafts on which the sample is mounted In a focused ion beam and electron beam combined apparatus comprising a sample stage that moves in a three-dimensional space, a focused ion beam irradiated from the focused ion beam column, an electron beam irradiated from the electron beam column, The inert ion beam irradiated from the active ion beam column is placed at the same location on the surface of the sample placed on the sample stage. Is arranged to be irradiated by comprising an angle, characterized in that is.

図１は、本発明による集束イオンビーム及び電子ビーム複合装置の一構成例である。
図２は、本発明による集束イオンビーム及び電子ビーム複合装置に用いられる試料ステージの動作に関する説明図である。
図３は、本発明による方法の一実施例である。
図４は、試料ステージのチルト方向を示す説明図で、（ａ）は正面図、（ｂ）はその側面図である。
図５は、本発明による集束イオンビーム及び電子ビーム複合装置の一構成例である。
図６は、本発明による集束イオンビーム及び電子ビーム複合装置に用いられる試料ステージの動作に関する説明図である。
図７は、本発明による方法の一実施例である。FIG. 1 is a configuration example of a focused ion beam and electron beam combined apparatus according to the present invention.
FIG. 2 is an explanatory diagram relating to the operation of the sample stage used in the focused ion beam and electron beam combined apparatus according to the present invention.
FIG. 3 is an example of a method according to the invention.
4A and 4B are explanatory views showing the tilt direction of the sample stage, in which FIG. 4A is a front view and FIG. 4B is a side view thereof.
FIG. 5 is a configuration example of a focused ion beam and electron beam combined apparatus according to the present invention.
FIG. 6 is an explanatory diagram regarding the operation of the sample stage used in the focused ion beam and electron beam combined apparatus according to the present invention.
FIG. 7 is an example of a method according to the invention.

本発明の装置の第一の実施例を図１を参照して説明する。
液体金属イオン源から発生するイオンを集束イオン光学系で集束し、試料表面に焦点を合わせて走査照射する集束イオンビーム鏡筒１０１と、エミッタチップから発生する電子を電子ビーム光学系で集束し、試料表面に焦点を合わせて走査照射する電子ビーム鏡筒１０２と、アルゴンなどの不活性イオンビームを発生して試料に照射する不活性イオンビーム鏡筒１０３が試料室１０４に取り付けられている。試料室内は、真空ポンプ１０５によって真空排気され、高真空状態を保持している。試料室１０４の内側には、試料１０６を載置して移動する試料ステージ７が設置されている。
集束イオンビーム鏡筒１０１と、電子ビーム鏡筒１０２と、不活性イオンビーム鏡筒１０３は、同一平面上に配置されている。そして、集束イオンビーム鏡筒１０１から発射される集束イオンビームと、電子ビーム鏡筒１０２から発射される電子ビームと、不活性イオンビーム鏡筒１０３から発射される不活性イオンビームは、試料ステージ１０７に載置された試料１０６の表面一箇所で交差するように調整されている。このとき、集束イオンビーム鏡筒１０１、電子ビーム鏡筒１０２、不活性イオンビーム鏡筒１０３の配置は、入れ替えても良い。
試料ステージ１０７は、複数の駆動軸を持っていて、試料１０６を載置して三次元空間を移動可能となっているが、図２に示すように、集束イオンビーム鏡筒１０１、電子ビーム鏡筒１０２、不活性イオンビーム鏡筒１０３を含む第一の平面２０１に対して直交する第二の平面２０２を基準とし、その交差角度が変更可能な構造になっている。その交差角度の変更可能範囲は、少なくとも±３度あれば良い。これは、試料の側壁を試料表面に対して垂直に立てるために設けられる傾斜角度である。実験的にこの程度の角度傾斜することができれば、目的を達成できる。すなわち、試料の側壁面の傾斜を補正することができる。
集束イオンビーム鏡筒１０１から発射されて試料表面を走査照射される集束イオンビームは、試料１０６の表面の被加工領域をスパッタリングエッチング加工する。同時に、電子ビーム鏡筒１０２から発射されて試料表面を走査照射される電子ビームは、試料１０６の表面の被加工領域を含む領域に走査照射される。そして、試料１０６表面から発生する電子などの二次荷電粒子を図１には図示されていない二次荷電粒子検出器にて検出し、同じく図示されていない装置制御システムにて走査電子顕微鏡像となる。
本装置を用いて薄片試料を作製する場合、集束イオンビームにてスパッタリングエッチング加工している状態を電子ビーム走査照射による走査電子顕微鏡像で観察し、薄片の厚さが設定された厚さになったところで、装置制御システムは集束イオンビームの試料への照射を終了する。
また、集束イオンビームにて薄片を所定の厚さに加工した後に、不活性イオンビーム鏡筒１０３から発射される不活性イオンビームを試料１０６表面の薄片周辺に照射してスパッタリングエッチング加工を行うのと同時に、電子ビームを走査照射して薄膜周辺を走査電子顕微鏡像で観察し、薄片の厚さが設定された厚さになったところで、装置制御システムは不活性イオンビームの試料への照射を終了する。
本発明による装置の第二の実施例を図５を参照して説明する。
液体金属イオン源から発生するイオンを集束イオン光学系で集束し、試料表面に焦点を合わせて走査照射する集束イオンビーム鏡筒５０１と、エミッタチップから発生する電子を電子ビーム光学系で集束し、試料表面に焦点を合わせて走査照射する電子ビーム鏡筒５０２と、アルゴンなどの不活性イオンビームを発生して試料に照射する不活性イオンビーム鏡筒５０３が試料室５０４に取り付けられている。試料室内は、真空ポンプ５０５によって真空排気され、高真空状態を保持している。試料室５０４の内側には、試料５０６を載置して移動する試料ステージ５０７が設置されている。
集束イオンビーム鏡筒５０１と、電子ビーム鏡筒５０２と、不活性イオンビーム鏡筒５０３は、集束イオンビーム鏡筒５０１から発射される集束イオンビームと、電子ビーム鏡筒５０２から発射される電子ビームと、不活性イオンビーム鏡筒５０３から発射される不活性イオンビームは、試料ステージ５０７に載置された試料５０６の表面一箇所で交差するように調整されている。
試料ステージ５０７は、複数の駆動軸を持っていて、試料５０６を載置して三次元空間を移動可能となっているが、図６に示すように、集束イオンビーム鏡筒６０１、不活性イオンビーム鏡筒６０３を含む第一の平面６０８に対して直交する第二の平面６０９を基準とし、その交差角度が変更可能な構造になっている。不活性イオンビームを照射するにあたり、試料への入射角度を変更することにより、不活性イオンビームによるエッチングで発生した再付着物の試料表面の残存を最小限に抑制する。
本装置を用いて薄片試料を作製する場合、集束イオンビームにてスパッタリングエッチング加工している試料５０６の露出した断面の状態を該断面への電子ビーム走査照射による走査電子顕微鏡像で観察し、薄片の厚さが設定された厚さになったところで、装置制御システムは集束イオンビームの試料への照射を終了する。このとき、試料の厚さは、試料の厚さ、材質などと、電子ビームの加速電圧で決まる透過電子量の変化を測定することにより、測定する。通常、電子は試料を透過しないが、所定の加速電圧を超えたり、試料の厚さがある厚さ以下になったりすると、電子が試料を透過する。その結果、電子顕微鏡による観察像が透過電子の影響で変化する。この変化を見つけることにより試料の厚さを制御することができる。
また、集束イオンビームにて薄片を所定の厚さに加工した後に、試料５０６を載置した試料ステージ５０７を傾斜して、試料５０６の表面が電子ビーム鏡筒５０２と不活性イオンビーム鏡筒５０３とで形成される平面に対して概ね垂直になるようにする。不活性イオンビーム鏡筒５０３から発射される不活性イオンビームを試料５０６表面の薄片周辺に照射してスパッタリングエッチング加工を行うのと同時に、電子ビームを試料側壁に対して平行な方向から走査照射して薄膜周辺を走査電子顕微鏡像で観察し、薄片の厚さが設定された厚さになったところで、装置制御システムは不活性イオンビームの試料への照射を終了する。このとき、試料ステージ５０７を移動させて、不活性イオンビームの試料５０６への入射角度を変更し、試料に残るエッチングによる再付着物を最小限にする。
図３に本発明による第一の実施例に示した装置を用いた方法の実施例を説明する。
図３ａに示すように、試料表面の薄片として残す領域３０１の周囲に、加工枠３０２ａ、３０２ｂ、３０２ｃ、３０２ｄを設定する。加速電圧が高く、エッチング速度の速い第一の集束イオンビーム条件にて集束イオンビーム３１１を用いたスパッタリングエッチング加工を行う。その結果、薄片として残す領域３０１を含んだ領域の周囲がエッチング加工される。
続いて、図３ｂに示すように、薄片として残す領域３０１の一方の側壁側に加工枠３０３を設定する。そして、試料を傾斜させて、第一の集束イオンビーム条件と比較してビーム径の小さい第二の集束イオンビーム条件にて集束イオンビーム３１２を走査照射してスパッタリングエッチング加工を行う。傾斜角度は、薄片の側壁が試料表面に対して垂直になるように設定するものとする。このとき同時に、薄片の側壁に対して平行な方向から電子ビーム３１４を走査照射して、薄片の表面を走査電子顕微鏡観察する。そして、薄片の厚さが所定の厚さになったところで、集束イオンビーム３１２の照射を終了する。
続いて、図３ｃに示すように、薄片として残す領域３０１のもう一方の側壁側に加工枠３０４を設定する。そして、試料を傾斜させて、第二の集束イオンビーム条件にて集束イオンビーム３１２を走査照射してスパッタリングエッチング加工を行う。このときの傾斜角度は他方の傾斜と同じ条件で決定する。図３ｂの工程と同様に、電子ビーム３１４を薄片の側壁に対して平行な方向から走査照射して、薄片の表面を走査電子顕微鏡観察する。そして、薄片の厚さが所定の厚さになったところで、集束イオンビーム３１２の照射を終了する。
続いて、図３ｄに示すように、試料を傾斜して、第三の集束イオンビーム条件にて集束イオンビーム３１３を走査照射してスパッタリングエッチング加工を行う。そして、薄片３０６を試料から切り離し、ＴＥＭ観察用グリッド３０７に移す。
薄片３０６に残る集束イオンビームのスパッタリングエッチング加工による損傷が、透過電子顕微鏡による観察に影響する場合、第二の集束イオンビーム条件において、加速電圧を１０ｋＶ以下の低い電圧に設定して行なっても良い。
続いて、図３ｅに示すように、薄片３０６をＴＥＭ観察用グリッド３０７に移し、薄片３０６を含む領域３０５に不活性イオンビーム３１５を照射して、薄片周辺をスパッタリングエッチング加工する。そのとき、不活性イオンビーム３１５は薄片３０６の側壁に概ね平行な方向から照射する。そして、薄片周辺に薄片３０６の側壁に対して平行な方向から電子ビーム３１４を走査照射して、薄片３０６の表面を走査電子顕微鏡観察し、薄片の厚さが所定の厚さになったところで、不活性イオンビーム３１５の照射を終了する。また、このとき、不活性イオンビーム３１５の照射角度が変わるよう試料ステージを移動させても良い。
図７に本発明による第二の実施例に示した装置を用いた方法の実施例を説明する。
図７ａに示すように、試料表面の薄片として残す領域７０１の周囲に、加工枠７０２ａ、７０２ｂ、７０２ｃ、７０２ｄを設定する。加速電圧が高く、エッチング速度の速い第一の集束イオンビーム条件にてスパッタリングエッチング加工を行う。その結果、薄片として残す領域７０１を含んだ領域の周囲がエッチング加工される。
続いて、図７ｂに示すように、薄片として残す領域７０１の一方の側壁側に加工枠７０３を設定する。そして、試料を傾斜させて、第一の集束イオンビーム条件と比較してビーム径の小さい第二の集束イオンビーム条件にて集束イオンビーム７１２を走査照射してスパッタリングエッチング加工を行う。傾斜角度は、薄片の側壁が試料表面に対して垂直になるように設定するものとする。このとき同時に、薄片の側壁に対しで垂直な方向から電子ビーム７１４を走査照射して、薄片の側壁を走査電子顕微鏡観察する。そして、透過電子量の相違から起きる観察像の明るさの変化から薄片の厚さを判断し、所定の厚さになったところで、集束イオンビーム７１２の照射を終了する。
続いて、図７ｃに示すように、薄片として残す領域７０１のもう一方の側壁側に加工枠７０４を設定する。そして、試料を傾斜させて、第二の集束イオンビーム条件にて集束イオンビーム７１２を走査照射してスパッタリングエッチング加工を行う。このときの傾斜角度は他方の傾斜と同じ条件で決定する。図７ｂの工程と同様に、電子ビーム７１４を薄片の側壁に対して垂直な方向から電子ビームを走査照射して、薄片の表面を走査電子顕微鏡観察する。そして、透過電子量の相違から起きる観察像の明るさの変化から薄片の厚さを判断し、所定の厚さになったところで、集束イオンビーム７１２の照射を終了する。
続いて、図７ｄに示すように、試料を傾斜して、第三の集束イオンビーム条件にて集束イオンビーム７１３を走査照射してスパッタリングエッチング加工を行う。そして、薄片７０６を試料から切り離し、ＴＥＭ観察用グリッド７０７に移す。
薄片７０６に残る集束イオンビームのスパッタリングエッチング加工による損傷が、透過電子顕微鏡による観察に影響する場合、第二の集束イオンビーム条件において、加速電圧を１０ｋＶ以下の低い電圧に設定して行なっても良い。
続いて、図７ｅに示すように、薄片７０６をＴＥＭ観察用グリッド７０７に移し、薄片７０６を含む領域７０５に不活性イオンビーム７１５を照射して、薄片周辺をスパッタリングエッチング加工する。そのとき、不活性イオンビーム７１５は薄片７０６の側壁に概ね平行な方向から照射する。そして、薄片周辺に薄片７０６の側壁に対して垂直な方向から電子ビーム７１４を走査照射して、薄片７０６の表面を走査電子顕微鏡観察する。そして、透過電子量の相違から起きる観察像の明るさの変化から薄片の厚さを判断し、所定の厚さになったところで、集束イオンビーム７１２の照射を終了する。
また、このとき、不活性イオンビーム７１５の照射角度が変わるよう試料ステージを移動させても良い。
産業上の利用性
本発明により、試料表面に薄片を形成する際に、その薄片の厚さを正確に制御することができる。また、実施例などで説明してないが、薄片の側壁に対して平行な方向から電子ビームを走査照射して薄片の厚さを観察していることから、薄片の上部のみならず、下部に至るまでの厚さの均一性も確認することができると言う効果を得ることができる。
又、側壁に垂直な方向から電子ビームを照射して厚みを測定することにより走査電子顕微鏡像の分解能によらず、膜厚を管理することができる。A first embodiment of the apparatus of the present invention will be described with reference to FIG.
Focusing ions generated from the liquid metal ion source with a focused ion optical system, focusing the sample surface and irradiating the sample with a focused ion beam column 101, focusing electrons generated from the emitter tip with an electron beam optical system, An electron beam column 102 that scans and irradiates the sample surface in focus and an inert ion beam column 103 that generates an inert ion beam such as argon and irradiates the sample are attached to the sample chamber 104. The sample chamber is evacuated by a vacuum pump 105 to maintain a high vacuum state. A sample stage 7 on which the sample 106 is placed and moved is installed inside the sample chamber 104.
The focused ion beam column 101, the electron beam column 102, and the inert ion beam column 103 are arranged on the same plane. The focused ion beam emitted from the focused ion beam column 101, the electron beam emitted from the electron beam column 102, and the inert ion beam emitted from the inert ion beam column 103 are converted into the sample stage 107. It is adjusted so as to intersect at one place on the surface of the sample 106 placed on the surface. At this time, the arrangement of the focused ion beam column 101, the electron beam column 102, and the inert ion beam column 103 may be switched.
The sample stage 107 has a plurality of drive shafts and can move in the three-dimensional space by placing the sample 106. As shown in FIG. 2, the focused ion beam column 101, the electron beam mirror, The second plane 202 orthogonal to the first plane 201 including the cylinder 102 and the inert ion beam column 103 is used as a reference, and the crossing angle can be changed. The changeable range of the intersection angle may be at least ± 3 degrees. This is an inclination angle provided to stand the side wall of the sample perpendicular to the sample surface. If the angle can be tilted experimentally, the object can be achieved. That is, the inclination of the side wall surface of the sample can be corrected.
The focused ion beam that is emitted from the focused ion beam column 101 and is irradiated with scanning on the sample surface performs sputtering etching on the processing region on the surface of the sample 106. At the same time, the electron beam emitted from the electron beam column 102 and scanned and irradiated on the sample surface scans and irradiates the region including the region to be processed on the surface of the sample 106. Then, secondary charged particles such as electrons generated from the surface of the sample 106 are detected by a secondary charged particle detector (not shown in FIG. 1), and a scanning electron microscope image is detected by an apparatus control system (not shown). Become.
When a thin piece sample is prepared using this device, the state of sputtering etching with a focused ion beam is observed with a scanning electron microscope image by electron beam scanning irradiation, and the thickness of the thin piece becomes a set thickness. Now, the apparatus control system ends irradiation of the sample with the focused ion beam.
In addition, after the thin piece is processed to a predetermined thickness with the focused ion beam, the inert ion beam emitted from the inert ion beam column 103 is irradiated to the periphery of the thin piece on the surface of the sample 106 to perform the sputtering etching process. At the same time, the electron beam is scanned and the periphery of the thin film is observed with a scanning electron microscope image. When the thickness of the flake reaches the set thickness, the device control system irradiates the sample with an inert ion beam. finish.
A second embodiment of the device according to the invention will be described with reference to FIG.
Ions generated from a liquid metal ion source are focused by a focused ion optical system, focused on a sample surface and scanned and irradiated, and electrons generated from an emitter tip are focused by an electron beam optical system, An electron beam column 502 that scans and irradiates the sample surface with focus, and an inert ion beam column 503 that generates an inert ion beam such as argon and irradiates the sample are attached to the sample chamber 504. The sample chamber is evacuated by a vacuum pump 505 to maintain a high vacuum state. Inside the sample chamber 504, a sample stage 507 on which the sample 506 is placed and moved is installed.
The focused ion beam column 501, the electron beam column 502, and the inert ion beam column 503 are a focused ion beam emitted from the focused ion beam column 501 and an electron beam emitted from the electron beam column 502. The inert ion beam emitted from the inert ion beam column 503 is adjusted so as to intersect at one place on the surface of the sample 506 placed on the sample stage 507.
The sample stage 507 has a plurality of drive shafts and can move in the three-dimensional space by placing the sample 506. As shown in FIG. 6, the focused ion beam column 601 and the inert ions are provided. The second plane 609 orthogonal to the first plane 608 including the beam column 603 is used as a reference, and the crossing angle can be changed. In irradiating the inert ion beam, by changing the incident angle to the sample, the remaining of the sample surface of the reattachment generated by the etching with the inert ion beam is minimized.
When a thin piece sample is produced using this apparatus, the state of the exposed cross section of the sample 506 subjected to sputtering etching with a focused ion beam is observed with a scanning electron microscope image by electron beam scanning irradiation on the cross section. When the thickness reaches the set thickness, the apparatus control system ends the irradiation of the sample with the focused ion beam. At this time, the thickness of the sample is measured by measuring the change in the amount of transmitted electrons determined by the thickness and material of the sample and the acceleration voltage of the electron beam. Normally, electrons do not pass through the sample. However, when a predetermined acceleration voltage is exceeded or the thickness of the sample falls below a certain thickness, the electron passes through the sample. As a result, the image observed by the electron microscope changes due to the influence of transmission electrons. By finding this change, the thickness of the sample can be controlled.
Further, after processing the flakes to a predetermined thickness with a focused ion beam, the sample stage 507 on which the sample 506 is placed is tilted so that the surface of the sample 506 has an electron beam column 502 and an inert ion beam column 503. And substantially perpendicular to the plane formed by Sputter etching is performed by irradiating the periphery of a thin piece on the surface of the sample 506 with an inert ion beam emitted from an inert ion beam column 503, and simultaneously, an electron beam is scanned and irradiated from a direction parallel to the sample side wall. Then, the periphery of the thin film is observed with a scanning electron microscope image, and when the thickness of the flake reaches the set thickness, the apparatus control system ends irradiation of the sample with the inert ion beam. At this time, the sample stage 507 is moved to change the incident angle of the inert ion beam to the sample 506, thereby minimizing the deposits remaining on the sample due to etching.
FIG. 3 illustrates an embodiment of a method using the apparatus shown in the first embodiment according to the present invention.
As shown in FIG. 3a, processing frames 302a, 302b, 302c, and 302d are set around a region 301 to be left as a thin piece on the sample surface. Sputter etching processing using the focused ion beam 311 is performed under the first focused ion beam condition where the acceleration voltage is high and the etching rate is high. As a result, the periphery of the region including the region 301 to be left as a flake is etched.
Subsequently, as shown in FIG. 3b, a processing frame 303 is set on one side wall side of the region 301 to be left as a thin piece. Then, the sample is tilted, and the sputter etching process is performed by scanning and irradiating the focused ion beam 312 under the second focused ion beam condition where the beam diameter is smaller than the first focused ion beam condition. The inclination angle is set so that the side wall of the slice is perpendicular to the sample surface. At the same time, the electron beam 314 is scanned and irradiated from a direction parallel to the side wall of the thin piece, and the surface of the thin piece is observed with a scanning electron microscope. When the thickness of the thin piece reaches a predetermined thickness, the irradiation of the focused ion beam 312 is finished.
Subsequently, as shown in FIG. 3c, a processing frame 304 is set on the other side wall side of the region 301 to be left as a thin piece. Then, the sample is tilted, and the focused ion beam 312 is scanned and irradiated under the second focused ion beam condition to perform sputtering etching. The inclination angle at this time is determined under the same conditions as the other inclination. Similar to the process of FIG. 3b, the electron beam 314 is scanned and irradiated from a direction parallel to the side wall of the thin piece, and the surface of the thin piece is observed with a scanning electron microscope. When the thickness of the thin piece reaches a predetermined thickness, the irradiation of the focused ion beam 312 is finished.
Subsequently, as shown in FIG. 3d, the sample is tilted, and the focused ion beam 313 is scanned and irradiated under the third focused ion beam condition to perform the sputtering etching process. Then, the thin piece 306 is separated from the sample and transferred to the TEM observation grid 307.
When damage caused by sputtering etching of the focused ion beam remaining on the thin piece 306 affects observation by a transmission electron microscope, the acceleration voltage may be set to a low voltage of 10 kV or less under the second focused ion beam condition. .
Subsequently, as shown in FIG. 3E, the thin piece 306 is transferred to the TEM observation grid 307, and the region 305 including the thin piece 306 is irradiated with an inert ion beam 315, and the periphery of the thin piece is processed by sputtering etching. At that time, the inert ion beam 315 is irradiated from a direction substantially parallel to the side wall of the thin piece 306. Then, the periphery of the thin piece is scanned and irradiated with an electron beam 314 from a direction parallel to the side wall of the thin piece 306, the surface of the thin piece 306 is observed with a scanning electron microscope, and when the thickness of the thin piece reaches a predetermined thickness, Irradiation with the inert ion beam 315 is terminated. At this time, the sample stage may be moved so that the irradiation angle of the inert ion beam 315 changes.
FIG. 7 illustrates an embodiment of the method using the apparatus shown in the second embodiment of the present invention.
As shown in FIG. 7a, processing frames 702a, 702b, 702c, and 702d are set around a region 701 to be left as a thin piece on the sample surface. Sputter etching is performed under the first focused ion beam condition where the acceleration voltage is high and the etching rate is high. As a result, the periphery of the region including the region 701 to be left as a flake is etched.
Subsequently, as shown in FIG. 7b, a processing frame 703 is set on one side wall side of the region 701 to be left as a thin piece. Then, the sample is tilted, and the sputter etching process is performed by scanning and irradiating the focused ion beam 712 under the second focused ion beam condition in which the beam diameter is smaller than the first focused ion beam condition. The inclination angle is set so that the side wall of the slice is perpendicular to the sample surface. At the same time, the electron beam 714 is scanned and irradiated from a direction perpendicular to the side wall of the thin piece, and the side wall of the thin piece is observed with a scanning electron microscope. Then, the thickness of the slice is determined from the change in the brightness of the observation image caused by the difference in the amount of transmitted electrons. When the thickness reaches a predetermined thickness, the irradiation of the focused ion beam 712 is terminated.
Subsequently, as shown in FIG. 7c, a processing frame 704 is set on the other side wall side of the region 701 to be left as a thin piece. Then, the sample is tilted, and scanning etching is performed by scanning irradiation with the focused ion beam 712 under the second focused ion beam condition. The inclination angle at this time is determined under the same conditions as the other inclination. Similar to the process of FIG. 7b, the electron beam 714 is scanned and irradiated from a direction perpendicular to the side wall of the thin piece, and the surface of the thin piece is observed with a scanning electron microscope. Then, the thickness of the slice is determined from the change in the brightness of the observation image caused by the difference in the amount of transmitted electrons. When the thickness reaches a predetermined thickness, the irradiation of the focused ion beam 712 is terminated.
Subsequently, as shown in FIG. 7d, the sample is tilted, and the focused ion beam 713 is scanned and irradiated under the third focused ion beam condition to perform the sputtering etching process. Then, the thin piece 706 is separated from the sample and transferred to the TEM observation grid 707.
When damage caused by sputtering etching of the focused ion beam remaining on the thin piece 706 affects observation with a transmission electron microscope, the acceleration voltage may be set to a low voltage of 10 kV or less under the second focused ion beam condition. .
Subsequently, as shown in FIG. 7e, the thin piece 706 is transferred to the TEM observation grid 707, and the region 705 including the thin piece 706 is irradiated with an inert ion beam 715, and the periphery of the thin piece is processed by sputtering etching. At that time, the inert ion beam 715 is irradiated from a direction substantially parallel to the side wall of the thin piece 706. Then, the surface of the thin piece 706 is observed with a scanning electron microscope by irradiating the periphery of the thin piece with an electron beam 714 from a direction perpendicular to the side wall of the thin piece 706. Then, the thickness of the slice is determined from the change in the brightness of the observation image caused by the difference in the amount of transmitted electrons. When the thickness reaches a predetermined thickness, the irradiation of the focused ion beam 712 is terminated.
At this time, the sample stage may be moved so that the irradiation angle of the inert ion beam 715 changes.
Industrial Applicability According to the present invention, when a flake is formed on the sample surface, the thickness of the flake can be accurately controlled. In addition, although not described in the examples, since the thickness of the thin piece is observed by scanning and irradiating the electron beam from a direction parallel to the side wall of the thin piece, not only the upper part of the thin piece but also the lower part. It is possible to obtain an effect that the uniformity of the thickness up to can be confirmed.
Further, by measuring the thickness by irradiating the electron beam from the direction perpendicular to the side wall, the film thickness can be managed regardless of the resolution of the scanning electron microscope image.

Claims

In the method of producing a thin piece sample by scanning and irradiating a focused ion beam on the sample surface, the thin piece portion is produced by the focused ion beam etching process, or the irradiation of the focused ion beam is temporarily interrupted, A method for preparing a thin piece sample, comprising: scanning and irradiating an electron beam in a direction parallel to the side wall of the produced thin piece portion, observing the surface portion of the thin piece with a microscope, and measuring the thickness of the thin piece portion .

The method for preparing a thin piece sample according to claim 1, wherein the etching process is terminated after confirming that the thickness of the thin piece sample has reached a predetermined thickness.

In a method of making a thin piece sample by scanning irradiation of the sample surface with a focused ion beam and etching it,
A first step of etching both sides of a region to be sliced using a focused ion beam under a first focused ion beam condition;
Subsequent to the first step, the focused ion beam is used to flake at a second focused ion beam condition that has a low acceleration voltage and / or a low beam current compared to the first focused ion beam condition. The side wall is etched by irradiating a focused ion beam in a direction parallel to the side wall of the region, and at the same time, an electron beam is scanned and irradiated from the direction parallel to the side wall of the region to be the thin piece to form the thin piece. A thin piece sample preparation method comprising: a second step of observing a surface portion of a power region under a microscope and measuring a thickness of the region to be the thin piece.

The second step is performed on the first side wall of the region to be flakes to form the first desired thickness, and then the second side wall of the region to be flakes is second. The thin film sample manufacturing method according to claim 3, wherein the step is performed to form the predetermined thickness.

In the second step, when the side wall of the region to be thinned is etched, the sample is tilted so that the focused ion beam is irradiated to the side wall to correct the tilt. The method for preparing a thin piece sample according to claim 3 or 4.

In a method of making a thin piece sample by scanning irradiation of the sample surface with a focused ion beam and etching it,
A first step of producing a flake by etching both sides of a region to be flake using a focused ion beam;
The specimen is tilted so that the first side wall of the flake is irradiated with a focused ion beam so as to correct the tilt, and the focused ion beam is scanned and irradiated to perform etching or simultaneously with the focused ion beam. Is temporarily suspended, scanning with an electron beam substantially parallel to the side wall of the thin piece portion, and observing the surface portion of the thin piece portion with a microscope, the thickness of the thin piece portion is set to a first predetermined thickness. A second step of confirming that the etching process is finished,
The sample is tilted so that the second side wall of the thin piece portion is irradiated with a focused ion beam so as to correct the tilt, and the focused ion beam is scanned and irradiated to perform etching, or the focusing is performed. The ion beam irradiation is temporarily interrupted, the electron beam is scanned and irradiated in parallel with the side wall of the thin piece, the surface portion of the thin piece portion is observed with a microscope, and the thickness of the thin piece portion is a second predetermined thickness. A third step to finish etching after confirming that
Subsequent to the third step, irradiation with an inert ion beam is performed to perform sputtering etching on both sides of the thin piece portion, or the irradiation of the inert ion beam is temporarily interrupted and parallel to the side wall of the thin piece portion. Scanning irradiation with an electron beam to observe the surface portion of the thin piece under a microscope, measuring the thickness of the thin piece portion, confirming that the thickness of the thin piece portion is a third predetermined thickness, A fourth step of ending the sputtering etching process with an inert ion beam;
A method for preparing a thin piece sample, comprising:

In a method of making a thin piece sample by scanning irradiation of the sample surface with a focused ion beam and etching it,
A first step of producing a flake by etching both sides of a region to be flake using a focused ion beam;
The specimen is tilted so that the first side wall of the flake is irradiated with a focused ion beam so as to correct the tilt, and the focused ion beam is scanned and irradiated to perform etching or simultaneously with the focused ion beam. Is temporarily suspended, the electron beam is scanned and irradiated almost perpendicularly to the side wall of the book piece portion, the amount of electrons transmitted through the thin piece portion is measured, and the thickness of the thin piece portion is determined from the change in the amount of electrons. A second step of confirming that the first predetermined thickness is reached and ending the etching process;
The sample is tilted so that the second side wall of the thin piece portion is irradiated with a focused ion beam so as to correct the tilt, and the focused ion beam is scanned and irradiated to perform etching, or the focusing is performed. The ion beam irradiation is temporarily interrupted, the electron beam is scanned and irradiated almost perpendicularly to the side wall of the thin piece, the amount of electrons transmitted through the thin piece portion is measured, and the thickness of the thin piece portion is determined from the change in the amount of electrons. A third step of confirming that the second predetermined thickness is reached and ending the etching;
Following the third step, irradiation with an inert ion beam is performed to perform sputtering etching on both sides of the thin piece portion, or at the same time as the irradiation of the inert ion beam is stopped, in parallel with the side wall of the thin piece portion. Scanning irradiation with an electron beam and observing the surface portion of the thin piece with a microscope, measuring the thickness of the thin piece portion, confirming that the thickness of the thin piece portion becomes a third predetermined thickness, and A fourth step of ending the sputtering etching process using an active ion beam;
A method for preparing a thin piece sample, comprising:

In a method of making a thin piece sample by scanning irradiation of the sample surface with a focused ion beam and etching it,
A first step of producing a flake by etching both sides of a region to be flake using a focused ion beam;
The specimen is tilted so that the first side wall of the flake is irradiated with a focused ion beam so as to correct the tilt, and the focused ion beam is scanned and irradiated to perform etching or simultaneously with the focused ion beam. Is temporarily interrupted, the surface of the thin piece portion is scanned and irradiated from the direction substantially parallel to the side wall of the thin piece portion, the surface portion of the thin piece portion is observed with a microscope, and the thickness of the thin piece portion is first. A second step of confirming that the predetermined thickness is reached and ending the etching process;
The sample is tilted so that the second side wall of the thin piece portion is irradiated with a focused ion beam so as to correct the tilt, and the focused ion beam is scanned and irradiated to perform etching, or the focusing is performed. The ion beam irradiation is temporarily interrupted, the electron beam is scanned and irradiated substantially perpendicularly to the side wall of the thin piece, the amount of electrons transmitted through the thin piece portion is measured, and the thickness of the book piece portion is determined from the change in the amount of electrons. Confirming that the second predetermined thickness is reached and ending the etching,
Subsequent to the third step, irradiation with an inert ion beam is performed to perform sputtering etching on both sides of the thin piece portion, or the irradiation of the inert ion beam is temporarily interrupted and parallel to the side wall of the thin piece portion. Scanning irradiation with an electron beam to observe the surface portion of the thin piece under a microscope, measuring the thickness of the thin piece portion, confirming that the thickness of the thin piece portion is a third predetermined thickness, A fourth step of ending the sputtering etching process with an inert ion beam;
A method for preparing a thin piece sample, comprising:

In a method of making a thin piece sample by scanning irradiation of the sample surface with a focused ion beam and etching it,
A first step of producing a flake by etching both sides of a region to be flake using a focused ion beam;
The specimen is tilted so that the first side wall of the flake is irradiated with a focused ion beam so as to correct the tilt, and the focused ion beam is scanned and irradiated to perform etching or simultaneously with the focused ion beam. Is temporarily interrupted, and an electron beam is scanned and irradiated almost perpendicularly to the side wall of the thin piece portion to measure the amount of electrons transmitted through the thin piece portion, and the thickness of the thin piece portion is determined from the change in the amount of electrons. A second step of confirming that the predetermined thickness is reached and ending the etching process;
The sample is tilted so that the second side wall of the thin piece portion is irradiated with a focused ion beam so as to correct the tilt, and the focused ion beam is scanned and irradiated to perform etching, or the focusing is performed. The ion beam irradiation is temporarily interrupted, the electron beam is scanned and irradiated almost perpendicularly to the side wall of the thin piece, the amount of electrons transmitted through the thin piece portion is measured, and the thickness of the thin piece portion is determined from the change in the amount of electrons. A third step of confirming that the second predetermined thickness is reached and ending the etching;
Subsequent to the third step, irradiation of an inert ion beam is performed to perform sputtering etching on both sides of the thin piece portion, or at the same time as irradiation of the inert ion beam is stopped, so that the side wall of the thin piece portion is substantially perpendicular. The amount of electrons transmitted through the thin piece portion is measured by scanning with an electron beam, the thickness of the thin piece portion is measured from the change in the amount of electrons, and the thickness of the thin piece portion is a third predetermined thickness. A fourth step of confirming that the sputtering etching process by the inert ion beam is finished,
A method for preparing a thin piece sample, comprising:

A focused ion beam column that focuses and irradiates the sample surface with the ion beam generated from the ion source, an electron beam column that focuses and irradiates the sample surface with the electron beam generated from the electron source, and a sample are mounted. In a focused ion beam and electron beam combined apparatus consisting of a sample stage that moves and moves in a three-dimensional space with a plurality of drive shafts,
The focused ion beam irradiated from the focused ion beam column and the electron beam irradiated from the electron beam column are irradiated at different angles on the same part of the sample surface placed on the sample stage. The sample stage is at an angle with respect to the first plane with reference to a second plane perpendicular to the first plane formed by at least the focused ion beam column and the electron beam column. The charged particle beam apparatus is characterized by tilting so as to be changeable.

A focused ion beam column that focuses an ion beam generated from an ion source and scans and irradiates the sample surface; an electron beam column that focuses an electron beam generated from the electron source and scans and irradiates the sample surface; and inert ions Focusing consisting of an inert ion beam column that focuses the inert ion beam generated from the source and scans and irradiates the surface of the sample, and a sample stage that mounts the sample and moves it in three-dimensional space with multiple drive axes In an ion beam and electron beam combined device,
The focused ion beam column, the electron beam column, and the inert ion beam column are arranged on the same plane,
The focused ion beam irradiated from the focused ion beam column, the electron beam irradiated from the electron beam column, and the inert ion beam irradiated from the inert ion beam column are mounted on the sample stage. The sample stage is arranged to irradiate the same part of the sample surface at different angles, and the sample stage is formed by at least the focused ion beam column, the electron beam column, and the inert ion beam column. The charged particle beam apparatus is characterized in that the angle with respect to the first plane can be changed with reference to a second plane intersecting at right angles to the plane.

A focused ion beam column that focuses an ion beam generated from an ion source and scans and irradiates the sample surface; an electron beam column that focuses an electron beam generated from the electron source and scans and irradiates the sample surface; and inert ions Focusing consisting of an inert ion beam column that focuses the inert ion beam generated from the source and scans and irradiates the surface of the sample, and a sample stage that mounts the sample and moves it in three-dimensional space with multiple drive axes In an ion beam and electron beam combined device,
The focused ion beam irradiated from the focused ion beam column, the electron beam irradiated from the electron beam column, and the inert ion beam irradiated from the inert ion beam column are mounted on the sample stage. A compound charged particle beam apparatus, wherein the beam barrels are arranged so that the same spot on the surface of the placed sample is irradiated at different angles.