JP2003202266A - Vacuum ultraviolet spectral measuring device - Google Patents
Vacuum ultraviolet spectral measuring deviceInfo
- Publication number
- JP2003202266A JP2003202266A JP2002000096A JP2002000096A JP2003202266A JP 2003202266 A JP2003202266 A JP 2003202266A JP 2002000096 A JP2002000096 A JP 2002000096A JP 2002000096 A JP2002000096 A JP 2002000096A JP 2003202266 A JP2003202266 A JP 2003202266A
- Authority
- JP
- Japan
- Prior art keywords
- vacuum ultraviolet
- optical path
- gas
- vacuum
- measurement
- 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
Landscapes
- Spectrometry And Color Measurement (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】真空紫外波長領域（２００ｎ
ｍ以下から軟Ｘ線、Ｘ線に至る波長領域）において、光
学素子などの分光特性を高精度に測定する技術に関する
ものでる。TECHNICAL FIELD The vacuum ultraviolet wavelength region (200 n
In a wavelength range from m or less to soft X-rays and X-rays), the present invention relates to a technique for measuring the spectral characteristics of an optical element or the like with high accuracy.
【０００２】[0002]
【従来の技術】真空紫外波長領域（２００ｎｍ以下から
軟Ｘ線、Ｘ線に至る波長領域）の分光計測において、こ
の波長領域の放射は大気中の酸素分子により吸収されて
しまうために、測定環境を真空状態か、またはＮ2やＡ
ｒ等の気体で置換して測定を行う必要がある。2. Description of the Related Art In spectroscopic measurement in the vacuum ultraviolet wavelength range (wavelength range from 200 nm or less to soft X-rays and X-rays), the radiation in this wavelength range is absorbed by oxygen molecules in the atmosphere, and In vacuum or N 2 or A
It is necessary to substitute gas such as r for measurement.
【０００３】また測定環境を真空状態にした場合、装置
チャンバー内壁より放出されるＨ2、Ｈ2Ｏや装置チャン
バー内部に設置される各種機構部や電気部品などから発
生するＢ、ＮＨ4 +などの無機系汚染物質、その他有機系
汚染物質により被測定物である光学材料の表面が汚染さ
れ、光学素子の透過率や反射率測定に影響を与えてい
た。Further, when the measurement environment is in a vacuum state, H 2 and H 2 O emitted from the inner wall of the apparatus chamber, B generated from various mechanical parts and electric parts installed inside the apparatus chamber, NH 4 +, etc. The surface of the optical material, which is the object to be measured, is contaminated by the inorganic pollutants and other organic pollutants, which affects the transmittance and reflectance measurement of the optical element.
【０００４】この測定環境を真空状態にした場合に発生
する被測定物の表面汚染を避けるために、測定環境をＮ
２やＡｒ等の気体で置換して測定を行う方法が多用され
ている。この方法が特開２０００−１４６６９１に示さ
れている。In order to avoid the surface contamination of the object to be measured which occurs when the measurement environment is in a vacuum state, the measurement environment is set to N.
A method of substituting with a gas such as 2 or Ar and performing the measurement is often used. This method is disclosed in Japanese Patent Laid-Open No. 2000-146691.
【０００５】ここでは、分光測定の光学系光路空間を周
囲測定環境と隔離した小容積の空間とするための囲いを
設け、この空間内に真空紫外波長領域の放射を吸収して
しまうＯ2をこの波長領域に対して吸収の少ないＮ2など
の気体で置換させる方法が開示されている。Here, an enclosure is provided to make the optical path space of the optical system for spectroscopic measurement a small volume space which is isolated from the surrounding measurement environment, and O 2 which absorbs radiation in the vacuum ultraviolet wavelength region is provided in this space. There is disclosed a method of substituting a gas such as N 2 having a low absorption in this wavelength region.
【０００６】[0006]
【発明が解決しようとする課題】しかしながらこの従来
例では、分光測定と並行して真空紫外波長領域に対して
吸収の少ないＮ2などの気体をこの隔離された空間内に
ガス導入口と排出口を設けて循環置換させているので、
光分割手段であるチョッパー以降の参照系光路と測定系
光路の間で置換状態が時間的、空間的に均一にならず、
参照系光路と測定系光路における真空紫外波長の相対的
吸収差を安定にすることができない。However, in this conventional example, a gas such as N 2 having a small absorption in the vacuum ultraviolet wavelength region is introduced into this isolated space in parallel with the spectroscopic measurement. Since it is arranged and replaced by circulation,
The replacement state is not uniform in time and space between the reference system optical path after the chopper which is the light splitting means and the measurement system optical path,
The relative absorption difference between the vacuum ultraviolet wavelengths in the reference optical path and the measurement optical path cannot be stabilized.
【０００７】分光測定を高精度にするためには、この相
対的吸収差を一定にし光分割手段以降の光路における真
空紫外波長の放射束量を時間的、空間的に安定させる必
要がある。In order to make the spectroscopic measurement highly accurate, it is necessary to make this relative absorption difference constant and to stabilize the radiant flux quantity of the vacuum ultraviolet wavelength in the optical path after the light splitting means temporally and spatially.
【０００８】次にこの相対的吸収差について、両光路間
でどの程度のＯ2濃度差に管理しなければならないかを
説明する。図５は、真空紫外波長領域におけるＯ2の吸
収係数を示すグラフである（「Ａｂｓｏｒｐｔｉｏｎ
Ｃｏｅｆｆｉｃｉｅｎｔｓｏｆ Ｏｘｙｇｅｎ ｉｎ
ｔｈｅ Ｖａｃｕｕｍ Ｕｌｔｒａｖｉｏｌｅｔ」ＴＨ
Ｅ ＪＯＵＲＮＡＬ ＯＦ ＣＨＥＭＩＣＡＬ ＰＨＹ
ＳＩＣＳ Ｖｏｌ．２１Ｎｏ．６ １９５３）。Next, how much the difference in O 2 concentration between the two optical paths should be managed with respect to this relative absorption difference will be described. FIG. 5 is a graph showing the absorption coefficient of O 2 in the vacuum ultraviolet wavelength region (“Absorption”).
Coefficients of Oxygen in
the Vacuum Ultraviolet "TH
E JOURNAL OF CHEMICAL PHY
SICS Vol. 21 No. 6 1953).
【０００９】この図５から、測定環境がＯ2のみで充填
されている時、波長１５７ｎｍの吸収係数をα１５７と
するとα１５７＝１８０［ｃｍ-1］である。放射束が伝
播する光路の長さをｔとすると、その時の放射束の透過
率Ｔは、Ｔ＝１０-(α157×t )と表わされる。From FIG. 5, when the measurement environment is filled with O 2 only, assuming that the absorption coefficient at the wavelength of 157 nm is α157, α157 = 180 [cm −1 ]. When the length of the optical path through which the radiant flux propagates is t, the transmittance T of the radiant flux at that time is expressed as T = 10 − ( α 157 × t ) .
【００１０】別の表現に置き換えると、測定環境が真空
紫外波長領域に対して吸収の少ないＮ2などの気体で充
填されているにも係わらず、極微量に残存するＯ2によ
る吸収の影響を受けて波長１５７ｎｍの放射束が長さｔ
の距離を伝播する時に透過率がＴになったとすると、こ
の長さｔの空間における吸収係数αは、α＝（−ｌｏｇ
Ｔ／ｔ）と表わされる。In other words, even if the measurement environment is filled with a gas such as N 2 which has a small absorption in the vacuum ultraviolet wavelength region, the influence of absorption by O 2 remaining in a very small amount Then, the radiant flux with a wavelength of 157 nm has a length t
Assuming that the transmittance becomes T when propagating a distance of, the absorption coefficient α in the space of this length t is α = (− log
T / t).
【００１１】分光測定の手順は、まず第１に測定系光路
から被測定物である光学素子を退避させた状態で参照系
光路と測定系光路の受光素子の各出力をＰｒ０、Ｐｍ０
として測定し、第２に測定系光路に光学素子を設置して
参照系光路と測定系光路の受光素子の各出力をＰｒ、Ｐ
ｍとして測定する。光学素子の透過率Ｔｓを測定する場
合は、Ｔｓ＝（Ｐｍ／Ｐｍ０）×（Ｐｒ０／Ｐｒ）より
算出する。The procedure of the spectroscopic measurement is as follows. First, the outputs of the light receiving elements of the reference system optical path and the measurement system optical path are Pr0 and Pm0 with the optical element being the object to be measured retracted from the measurement system optical path.
Secondly, an optical element is installed in the optical path of the measurement system, and the outputs of the light receiving elements of the optical path of the reference system and the optical path of the measurement system are set to Pr and P, respectively.
Measure as m. When measuring the transmittance Ts of the optical element, it is calculated from Ts = (Pm / Pm0) × (Pr0 / Pr).
【００１２】この透過率Ｔｓを測定する際、前述の第１
の状態、即ち被測定物である光学素子を退避させた状態
で参照系光路と測定系光路の両光路間に極微量に残存す
るＯ 2の濃度に相対差がないと仮定すると、各系のＯ2濃
度は、参照系光路：α／α１５７＝（−ｌｏｇＴ／ｔ）
／α１５７と同じであるが、前述の第２の状態、即ち被
測定物である光学素子を光路に設置した状態で参照系光
路のＯ2濃度は不変であったが、測定系光路のＯ2濃度が
変化し、各々の系路の透過率がＴ、Ｔ’になったとする
と、その時のＯ2濃度は（−ｌｏｇＴ／ｔ）／α１５
７、（−ｌｏｇＴ’／ｔ）／α１５７と表わされる。When measuring the transmittance Ts, the above-mentioned first
State, that is, the state in which the measured optical element is retracted
A trace amount remains between the reference system optical path and the measurement system optical path.
O 2Assuming that there is no relative difference in the concentration of2Dark
Degree is the optical path of the reference system: α / α157 = (− logT / t)
/ Α157, but the second state described above, that is,
Reference system light with an optical element that is the object to be measured installed in the optical path
O of the road2The concentration was unchanged, but O in the optical path of the measurement system2Concentration
It is assumed that the transmittances of the respective paths have changed to T and T '.
And O at that time2The concentration is (-logT / t) / α15
7 and (-logT '/ t) / α157.
【００１３】透過率分光測定の測定精度を０．０５％以
下に抑制しようとするとＴ’／Ｔ＝１．０００５とな
り、前述の長さｔが３５ｃｍである時、相対的なＯ2濃
度差は、（−ｌｏｇＴ’／ｔ）／α１５７−（−ｌｏｇ
Ｔ／ｔ）／α１５７＝ｌｏｇ（Ｔ／Ｔ’）／（α１５７
×ｔ）＝ｌｏｇ（１／１．０００５）／（１８０×３
５）＝０．０３４［ｐｐｍ］となり、かなり厳しい相対
Ｏ2濃度差の管理が必要になることが分かる。In order to suppress the measurement accuracy of the transmittance spectroscopic measurement to 0.05% or less, T '/ T = 1.0005, and when the length t is 35 cm, the relative O 2 concentration difference is , (-LogT '/ t) / α157-(-log
T / t) / α157 = log (T / T ′) / (α157
× t) = log (1 / 1000.5) / (180 × 3)
5) = 0.034 [ppm], which shows that fairly strict control of the relative O 2 concentration difference is required.
【００１４】本発明は、真空紫外波長領域の分光測定に
おいて、測定環境が真空紫外波長領域の放射を吸収しに
くい気体で充填された状態であっても、極微量に残存す
るＯ 2濃度のために生ずる放射束の伝播量の時間的、空
間的変化を受け難くし、高精度な分光測定を行えるよう
にするものである。The present invention is applicable to spectroscopic measurement in the vacuum ultraviolet wavelength region.
In order to absorb the radiation in the vacuum ultraviolet wavelength range,
Even if it is filled with scavenging gas, a very small amount remains
O 2The amount of radiant flux propagation due to concentration
Achieves highly accurate spectroscopic measurement by making it less susceptible to changes over time
It is something to do.
【００１５】[0015]
【課題を解決するための手段】第１に、真空紫外分光測
定装置において、測定環境が真空紫外波長領域の放射を
吸収しにくい気体で充填された状態で、光源から射出す
る放射束を光分割手段により分岐する光路があり、その
光分割手段から受光素子に至るまでの光路に周囲測定環
境の気体と隔離された真空部分が形成されているか、ま
たは真空紫外領域の波長が透過する光学部材を設置した
真空紫外分光測定装置。First, in a vacuum ultraviolet spectroscopic measurement apparatus, a radiant flux emitted from a light source is optically split while the measurement environment is filled with a gas that hardly absorbs radiation in the vacuum ultraviolet wavelength range. There is an optical path branched by the means, a vacuum portion isolated from the gas of the surrounding measurement environment is formed in the optical path from the light splitting means to the light receiving element, or an optical member that transmits a wavelength in the vacuum ultraviolet region is used. Vacuum ultraviolet spectrophotometer installed.
【００１６】第２に、真空紫外分光測定装置において、
測定環境が真空紫外波長領域の放射を吸収しにくい気体
で充填された状態で、光源から受光素子までの光路内に
周囲測定環境の気体と隔離された真空部分が形成されて
いるか、または真空紫外領域の波長が透過する光学部材
を設置した真空紫外分光測定装置。Secondly, in the vacuum ultraviolet spectrometer,
When the measurement environment is filled with a gas that does not easily absorb radiation in the vacuum ultraviolet wavelength range, a vacuum part is formed in the optical path from the light source to the light receiving element, which is isolated from the gas of the surrounding measurement environment, or vacuum ultraviolet A vacuum ultraviolet spectrophotometer equipped with an optical member that transmits wavelengths in the region.
【００１７】[0017]
【発明の実施の形態】（第１の実施例）次に本発明の実
施形態について具他的に説明する。図１は光学素子の分
光特性を測定する装置の全体を表わす図で、参照系と測
定系の光路を有するダブルビーム方式で構成されてい
る。BEST MODE FOR CARRYING OUT THE INVENTION (First Embodiment) Next, embodiments of the present invention will be specifically described. FIG. 1 is a diagram showing an entire apparatus for measuring the spectral characteristic of an optical element, which is constructed by a double beam system having optical paths of a reference system and a measurement system.
【００１８】１は真空紫外波長領域の放射束を発する光
源ユニット、２は光源ユニット１からの放射束を所定波
長毎に分光する回折格子の分光手段と被測定物である光
学素子２５に対してほぼ平行な光束を入射させるための
投光手段を含んだ分光器ユニットである。Reference numeral 1 denotes a light source unit that emits a radiant flux in the vacuum ultraviolet wavelength range, and 2 denotes a spectral means of a diffraction grating that disperses the radiant flux from the light source unit 1 for each predetermined wavelength and an optical element 25 that is an object to be measured. It is a spectroscope unit including a light projecting means for making a substantially parallel light beam incident.
【００１９】３は装置チャンバーで内部の測定環境は真
空紫外波長領域の放射を吸収しにくい気体、例えばＮ２
やＡｒ等の気体で充填された状態になっている。４はそ
の気体を装置チャンバー内に供給する供給口で、５はそ
の気体の排気口である。Reference numeral 3 is an apparatus chamber, and the measurement environment inside is a gas that hardly absorbs radiation in the vacuum ultraviolet wavelength region, for example, N 2
It is filled with a gas such as Ar or Ar. Reference numeral 4 is a supply port for supplying the gas into the apparatus chamber, and 5 is an exhaust port for the gas.
【００２０】測定環境を真空状態にせず真空紫外波長領
域の放射を吸収しにくい気体にする理由は、従来例で説
明した通り、装置チャンバー内壁より放出されるＨ2、
Ｈ2Ｏや装置チャンバー内部に設置される各種機構部や
電気部品などから発生するＢ、ＮＨ4 +などの無機系汚染
物質、その他有機系汚染物質により被測定物である光学
材料の表面が汚染され、光学素子の透過率や反射率測定
に影響を与えるからである。As described in the conventional example, the reason why the measurement environment is set to a gas that does not easily absorb the radiation in the vacuum ultraviolet wavelength range without being in a vacuum state is that H 2 emitted from the inner wall of the apparatus chamber,
The surface of the optical material to be measured is contaminated with inorganic pollutants such as B and NH 4 + generated from H 2 O and various mechanical parts and electric parts installed inside the chamber of the equipment, and other organic pollutants. This affects the measurement of the transmittance and reflectance of the optical element.
【００２１】分光器ユニット２から射出した放射束は装
置チャンバー３内に入り光路６を通過する。次に半円状
のミラー７がモーターなどの回転駆動手段８と連結した
光分割手段９があり、反射により参照系光路１０、透過
により測定系光路１１へ光路６の放射束を時間的に振り
分けている。The radiant flux emitted from the spectroscope unit 2 enters the apparatus chamber 3 and passes through the optical path 6. Next, there is a light splitting means 9 in which a semicircular mirror 7 is connected to a rotation driving means 8 such as a motor, and the radiant flux of the optical path 6 is temporally distributed to the reference system optical path 10 by reflection and the measurement system optical path 11 by transmission. ing.
【００２２】参照系光路１０には光分割手段９から参照
系の受光素子１７に至る光路内に周囲測定環境の気体と
隔離された真空状態の部分１２が金属管などにより形成
されていて、真空紫外波長領域の放射束を透過させる光
学部材からなるウィンドウ１３、１４がそれぞれ入口と
出口に設けられ金属管の内部を密閉している。In the optical path 10 of the reference system, a portion 12 in a vacuum state isolated from the gas of the surrounding measurement environment is formed by a metal tube or the like in the optical path from the light splitting means 9 to the light receiving element 17 of the reference system. Windows 13 and 14 made of optical members for transmitting a radiant flux in the ultraviolet wavelength region are provided at the inlet and the outlet, respectively, to seal the inside of the metal tube.
【００２３】また参照系光路の配置において光路を曲げ
る必要がある場合は１２の一部にミラー１６を使用し、
配置に自由度をもたせることができる。また１２は装置
チャンバー３外部と連結した真空ポンプ１５により内部
が常時真空状態に維持されるようにしてある。Further, when it is necessary to bend the optical path in the arrangement of the reference system optical path, a mirror 16 is used for a part of 12,
There is a degree of freedom in placement. Further, 12 is such that the inside thereof is always maintained in a vacuum state by a vacuum pump 15 connected to the outside of the apparatus chamber 3.
【００２４】測定系光路１１は、参照系光路１０と同じ
く、光分割手段９から参照系の受光素子２４に至る光路
内に周囲測定環境の気体と隔離された真空状態の部分１
８が金属管などにより形成されていて、真空紫外波長領
域の放射束を透過させる光学部材からなるウィンドウ１
９、２０がそれぞれ入口と出口に設けられ金属管の内部
を密閉している。Similar to the reference system optical path 10, the measurement system optical path 11 is in a vacuum state portion 1 which is isolated from the gas in the surrounding measurement environment in the optical path from the light splitting means 9 to the light receiving element 24 of the reference system.
The window 1 is formed of a metal tube or the like, and is composed of an optical member that transmits a radiant flux in the vacuum ultraviolet wavelength range.
9 and 20 are respectively provided at the inlet and the outlet to seal the inside of the metal pipe.
【００２５】また参照系光路の配置において光路を曲げ
る必要がある場合は１８の一部にミラー２２を使用し、
配置に自由度をもたせることができる。また１８は装置
チャンバー３外部と連結した真空ポンプ２１により内部
が常時真空状態に維持されるようにしてある。When it is necessary to bend the optical path in the arrangement of the reference system optical path, a mirror 22 is used in a part of 18,
There is a degree of freedom in placement. A vacuum pump 21 connected to the outside of the apparatus chamber 3 always keeps the inside vacuum.
【００２６】このように構成された真空紫外波長領域の
分光測定において、分光測定の手順は、まず第１に測定
系光路１１から被測定物である光学素子２４を退避させ
た状態で参照系光路１０と測定系光路１１の受光素子の
各出力をＰｒ０、Ｐｍ０として測定し、第２に測定系光
路１１に光学素子２５を設置して参照系光路１０と測定
系光路１１の受光素子１７、２３の各出力をＰｒ、Ｐｍ
として測定する。光学素子２４の透過率Ｔｓを測定する
場合は、Ｔｓ＝（Ｐｍ／Ｐｍ０）×（Ｐｒ０／Ｐｒ）よ
り算出する。In the spectroscopic measurement in the vacuum ultraviolet wavelength region constructed as described above, the spectroscopic measurement procedure is as follows. 10 and the outputs of the light receiving elements of the measurement system optical path 11 are measured as Pr0 and Pm0, and secondly, the optical element 25 is installed in the measurement system optical path 11 to receive the light receiving elements 17 and 23 of the reference system optical path 10 and the measurement system optical path 11. Each output of Pr, Pm
To measure. When measuring the transmittance Ts of the optical element 24, it is calculated from Ts = (Pm / Pm0) × (Pr0 / Pr).
【００２７】この測定の際、従来のように測定環境をＮ
２やＡｒ等の真空紫外波長領域の放射を吸収しにくい気
体で充填するために供給口４と排気口５による循環方法
の置換を行っていたが、この従来方法では光分割手段９
以降の参照系光路１０と測定系光路１１の間で置換状態
が時間的、空間的に均一にならず、参照系光路１０と測
定系光路１１における真空紫外波長放射の相対的なエネ
ルギー変動が発生することは避けられない。At the time of this measurement, the measurement environment is changed to N
In order to fill the radiation in the vacuum ultraviolet wavelength region such as 2 and Ar with a gas which is difficult to be absorbed, the supply port 4 and the exhaust port 5 have replaced the circulation method, but in this conventional method, the light splitting means 9 is used.
Subsequent replacement states are not temporally and spatially uniform between the reference system optical path 10 and the measurement system optical path 11, and relative energy fluctuations of vacuum ultraviolet wavelength radiation occur in the reference system optical path 10 and the measurement system optical path 11. It is inevitable to do.
【００２８】その影響は従来例で説明した通り、測定精
度を０．０５％以下に抑制しようとすると両光路間の相
対Ｏ2濃度差を［ｐｐｍ］にしなければならず、この分
解能でＯ2濃度差を検出し、かつ管理することは不可能
である。[0028] Its effect must as described in the conventional example, when the measurement accuracy attempts to suppress the 0.05% or less relative O 2 concentration difference between both optical paths [ppm], O 2 in the resolution It is impossible to detect and manage the density difference.
【００２９】分光測定を高精度に行うためには、この相
対的Ｏ2濃度差を一定にし光分割手段９以降の両光路１
０、１１における真空紫外波長の放射束量を時間的、空
間的に安定させる必要がある。In order to carry out the spectroscopic measurement with high precision, the relative O 2 concentration difference is kept constant and both optical paths 1 and the optical path after the light dividing means 9 are used.
It is necessary to stabilize the radiant flux amount of the vacuum ultraviolet wavelength at 0 and 11 temporally and spatially.
【００３０】そのために本発明が示すように、光分割手
段９から参照系、及び測定系の受光素子１７、２３に至
る光路内に周囲測定環境の気体と隔離された真空状態の
部分１２、１８を形成し、Ｏ2が残存しない部分を設け
て両光路間で相対Ｏ2濃度差が時間的、空間的に生じな
いようにすることが必要である。Therefore, as shown in the present invention, in the optical path from the light splitting means 9 to the light receiving elements 17 and 23 of the reference system and the measurement system, the portions 12 and 18 in a vacuum state isolated from the gas of the surrounding measurement environment. It is necessary to provide a portion where O 2 does not remain so that a relative O 2 concentration difference between both optical paths does not occur temporally and spatially.
【００３１】図２は本発明の別の構成を示す図で、前述
の真空状態の部分１２、１８の部分が真空紫外領域の波
長に対して透過なＣａＦ２、ＭｇＦ２などの光学部材２
５、２６で構成されている。FIG. 2 is a view showing another structure of the present invention. The above-mentioned optical parts 2 such as CaF2 and MgF2, which are transparent to the wavelengths in the vacuum ultraviolet region, are provided in the vacuumed parts 12 and 18.
It is composed of 5, 26.
【００３２】それ以外の構成は前述の説明と同じであ
る。この光学部材２５、２６を用いることによっても、
Ｏ2が残存しない部分を形成することができるので、両
光路間で相対Ｏ2濃度差が時間的、空間的に生じないよ
うにすることができる。The other configurations are the same as those described above. By using the optical members 25 and 26,
Since a portion where O 2 does not remain can be formed, it is possible to prevent a relative O 2 concentration difference between both optical paths from occurring temporally and spatially.
【００３３】従来の真空紫外波長領域の放射を吸収しに
くい気体の循環によるＯ2置換のみでは、一般的に参照
系光路と測定系光路の長さをほぼ等しい長さに設定する
必要があったが、本発明の構成を用いることにより、両
光路の長さを独立に設定することが可能で、装置チャン
バー３内部の光学配置の自由度を拡大することができ
る。In the conventional O 2 substitution only by circulation of a gas that hardly absorbs radiation in the vacuum ultraviolet wavelength region, it was generally necessary to set the reference system optical path and the measurement system optical path to substantially the same length. However, by using the configuration of the present invention, the lengths of both optical paths can be set independently, and the degree of freedom of the optical arrangement inside the apparatus chamber 3 can be expanded.
【００３４】（第２の実施例）図３は本発明の第２の実
施形態を表わす図で、シングルビーム方式で構成されて
いる。実施例１と比較して、光分割手段はなく参照系と
測定系を共通にした光路２８が設けられている。(Second Embodiment) FIG. 3 shows a second embodiment of the present invention, which is constructed by a single beam system. Compared to the first embodiment, there is no light splitting means and an optical path 28 having a common reference system and measurement system is provided.
【００３５】図３において、実施例１と同じ部材は同じ
番号を使用する。１は真空紫外波長領域の放射束を発す
る光源ユニット、２は光源ユニット１からの放射束を所
定波長毎に分光する回折格子の分光手段と被測定物であ
る光学素子２５に対してほぼ平行な光束を入射させるた
めの投光手段を含んだ分光器ユニットである。In FIG. 3, the same members as those in the first embodiment use the same numbers. Reference numeral 1 is a light source unit that emits a radiant flux in the vacuum ultraviolet wavelength region, and 2 is substantially parallel to a spectroscopic means of a diffraction grating that disperses the radiant flux from the light source unit 1 for each predetermined wavelength and an optical element 25 that is an object to be measured. It is a spectroscope unit including a light projecting means for making a light beam incident.
【００３６】３は装置チャンバーで内部の測定環境は真
空紫外波長領域の放射を吸収しにくい気体、例えばＮ２
やＡｒ等の気体で充填された状態になっている。４はそ
の気体を装置チャンバー内に供給する供給口で、５はそ
の気体の排気口である。Reference numeral 3 denotes an apparatus chamber, the measurement environment inside of which is a gas which hardly absorbs radiation in the vacuum ultraviolet wavelength region, for example N2.
It is filled with a gas such as Ar or Ar. Reference numeral 4 is a supply port for supplying the gas into the apparatus chamber, and 5 is an exhaust port for the gas.
【００３７】測定環境を真空状態にせず真空紫外波長領
域の放射を吸収しにくい気体にする理由は、従来例で説
明した通り、装置チャンバー内壁より放出されるＨ2、
Ｈ2Ｏや装置チャンバー内部に設置される各種機構部や
電気部品などから発生するＢ、ＮＨ4 +などの無機系汚染
物質、その他有機系汚染物質により被測定物である光学
材料の表面が汚染され、光学素子の透過率や反射率測定
に影響を与えるからである。As described in the conventional example, the reason why the measurement environment is set to a gas that does not easily absorb radiation in the vacuum ultraviolet wavelength range without being in a vacuum state is H 2 emitted from the inner wall of the apparatus chamber,
The surface of the optical material to be measured is contaminated with inorganic pollutants such as B and NH 4 + generated from H 2 O and various mechanical parts and electric parts installed inside the chamber of the equipment, and other organic pollutants. This affects the measurement of the transmittance and reflectance of the optical element.
【００３８】分光器ユニット２から射出した放射束は装
置チャンバー３内に入り光路２８を通過する。光路２７
から参照系の受光素子１７に至る光路内に周囲測定環境
の気体と隔離された真空状態の部分２８が金属管などに
より形成されていて、真空紫外波長領域の放射束を透過
させる光学部材からなるウィンドウ１３、１４がそれぞ
れ入口と出口に設けられ金属管の内部を密閉している。The radiant flux emitted from the spectroscope unit 2 enters the apparatus chamber 3 and passes through the optical path 28. Optical path 27
A portion 28 in a vacuum state isolated from the gas of the surrounding measurement environment is formed by a metal tube or the like in the optical path from the light receiving element 17 of the reference system to the light receiving element 17 of the reference system, and is composed of an optical member that transmits a radiant flux in the vacuum ultraviolet wavelength range. Windows 13 and 14 are provided at the inlet and the outlet to seal the inside of the metal tube.
【００３９】また真空状態の部分２８は装置チャンバー
３外部と連結した真空ポンプ１５により内部が常時真空
状態に維持されるようにしてある。分光測定の手順は、
まず第１に光路２７から被測定物である光学素子２４を
退避させた状態で受光素子２３の出力をＰｒとして測定
し、第２に光路２７に光学素子２５を設置して受光素子
２３のＰｍとして測定する。The inside of the vacuumed portion 28 is always maintained in a vacuum state by the vacuum pump 15 connected to the outside of the apparatus chamber 3. The spectroscopic measurement procedure is
First, the output of the light receiving element 23 is measured as Pr while the optical element 24, which is the object to be measured, is retracted from the optical path 27, and secondly, the optical element 25 is installed in the optical path 27 to set Pm of the light receiving element 23. To measure.
【００４０】光学素子２４の透過率Ｔｓを測定する場合
は、Ｔｓ＝Ｐｍ／Ｐｒより算出する。このシングルビー
ム方式の分光測定においても、実施例１と同様、第１と
第２の測定の間でＯ2の置換状態が時間的、空間的に均
一にならず、光路２８における真空紫外波長放射の相対
的なエネルギー変動が発生することは避けられない。When the transmittance Ts of the optical element 24 is measured, it is calculated from Ts = Pm / Pr. Also in this single-beam spectroscopic measurement, as in Example 1, the O 2 substitution state does not become temporally and spatially uniform between the first and second measurements, and the vacuum ultraviolet wavelength radiation in the optical path 28 occurs. It is unavoidable that the relative energy fluctuations of will occur.
【００４１】その影響は従来例で説明した通りである。
分光測定を高精度に行うために、光路２７内の受光素子
２４に至る間に周囲測定環境の気体と隔離された真空状
態の部分２８を形成し、Ｏ2が残存しない部分を設けて
前述の第１、第２の測定間でＯ2濃度差が時間的、空間
的に生じないようにすることが必要である。The influence is as described in the conventional example.
In order to perform the spectroscopic measurement with high accuracy, a portion 28 in a vacuum state isolated from the gas of the surrounding measurement environment is formed between the light receiving elements 24 in the optical path 27, and a portion where O 2 does not remain is provided. It is necessary to prevent the O 2 concentration difference between the first and second measurements from occurring temporally and spatially.
【００４２】図４は実施例の別の構成を示す図で、前述
の真空状態の部分２８が真空紫外領域の波長に対して透
過なＣａＦ2、ＭｇＦ2などの光学部材２９で構成されて
いる。それ以外の構成は前述の説明と同じである。FIG. 4 is a view showing another constitution of the embodiment, in which the above-mentioned vacuum state portion 28 is constituted by an optical member 29 such as CaF 2 or MgF 2 which is transparent to the wavelength in the vacuum ultraviolet region. . The other configurations are the same as those described above.
【００４３】この光学部材２９を用いることによって
も、Ｏ2が残存しない部分を形成することができるの
で、第１、第２の測定間でＯ2濃度差が時間的、空間的
に生じないようにすることができる。By using this optical member 29 as well, it is possible to form a portion in which O 2 does not remain, so that the O 2 concentration difference between the first and second measurements does not occur temporally or spatially. Can be
【００４４】[0044]
【発明の効果】真空紫外波長領域の分光測定装置におい
て、測定期間中に測定環境に残存するＯ2が真空紫外波
長の放射束量を時間的、空間的に変動させることを排除
し、従来必要であったサブｐｐｍ以下のＯ2濃度管理を
不要とする高精度な測定を実現することができる。INDUSTRIAL APPLICABILITY In the vacuum ultraviolet wavelength region spectroscopic measurement apparatus, O 2 remaining in the measurement environment during the measurement period is excluded from varying the radiant flux amount of the vacuum ultraviolet wavelength temporally and spatially, and is conventionally required. It is possible to realize highly accurate measurement that does not require O 2 concentration control of sub-ppm or less.
【図１】 実施例１で真空部分形成を用いた場合の図FIG. 1 is a diagram when a vacuum partial formation is used in Example 1.
【図２】 実施例１で真空紫外波長を透過する光学部材
を用いた場合の図FIG. 2 is a diagram when an optical member that transmits vacuum ultraviolet wavelengths is used in Example 1.
【図３】 実施例２で真空部分形成を用いた場合の図FIG. 3 is a diagram when a vacuum partial formation is used in Example 2.
【図４】 実施例２で真空紫外波長を透過する光学部材
を用いた場合の図FIG. 4 is a diagram when an optical member that transmits a vacuum ultraviolet wavelength is used in Example 2.
【図５】 真空紫外波長領域におけるＯ2の吸収係数を
示すグラフFIG. 5 is a graph showing the absorption coefficient of O 2 in the vacuum ultraviolet wavelength region.
【符号の説明】 ９ 光分割器 １０ 参照系光路 １１ 測定系光路 １２、１８ 真空部分 １７、２３ 受光素子 ２４ 光学素子 ２５、２６ 真空紫外波長領域に透過な光学部材 ２７ 光路 ２８ 真空部分 ２９ 真空紫外波長領域に透過な光学部材[Explanation of symbols] 9 Optical splitter 10 Reference system optical path 11 Measurement system optical path 12, 18 Vacuum part 17, 23 Light receiving element 24 Optical element 25, 26 Optical member transparent to vacuum ultraviolet wavelength range 27 optical path 28 Vacuum part 29 Optical member transparent to vacuum ultraviolet wavelength range
Claims (4)
境が真空紫外波長領域の放射を吸収しにくい気体で充填
された状態で、光源から射出する放射束を光分割手段に
より分岐する光路があり、その光分割手段から受光素子
に至るまでの光路に周囲測定環境の気体と隔離された真
空部分が形成されていることを特徴とする真空紫外分光
測定装置。1. A vacuum ultraviolet spectroscopic measurement apparatus has an optical path for branching a radiant flux emitted from a light source by a light splitting means in a state where the measurement environment is filled with a gas that hardly absorbs radiation in the vacuum ultraviolet wavelength region, A vacuum ultraviolet spectroscopic measurement device characterized in that a vacuum portion isolated from the gas of the surrounding measurement environment is formed in the optical path from the light splitting means to the light receiving element.
境が真空紫外波長領域の放射を吸収しにくい気体で充填
された状態で、光源から射出する放射束を光分割手段に
より分岐する光路があり、その光分割手段から受光素子
に至るまでの光路に真空紫外領域の波長が透過する光学
部材を設置したことを特徴とする真空紫外分光測定装
置。2. The vacuum ultraviolet spectroscopic measurement apparatus has an optical path for branching a radiant flux emitted from a light source by a light splitting means in a state where the measurement environment is filled with a gas that hardly absorbs radiation in the vacuum ultraviolet wavelength range, A vacuum ultraviolet spectroscopic measurement device characterized in that an optical member for transmitting wavelengths in the vacuum ultraviolet region is installed in the optical path from the light splitting means to the light receiving element.
境が真空紫外波長領域の放射を吸収しにくい気体で充填
された状態で、光源から受光素子までの光路内に周囲測
定環境の気体と隔離された真空部分が形成されているこ
とを特徴とする真空紫外分光測定装置。3. A vacuum ultraviolet spectrophotometer, wherein the measurement environment is filled with a gas that hardly absorbs radiation in the vacuum ultraviolet wavelength range, and is isolated from the gas in the surrounding measurement environment in the optical path from the light source to the light receiving element. A vacuum ultraviolet spectroscopic measurement device characterized in that a vacuum portion is formed.
境が真空紫外波長領域の放射を吸収しにくい気体で充填
された状態で、光源から受光素子までの光路内に真空紫
外領域の波長が透過する光学部材を設置したことを特徴
とする真空紫外分光測定装置。4. A vacuum ultraviolet spectroscopic measurement apparatus transmits a wavelength in the vacuum ultraviolet region in an optical path from a light source to a light receiving element in a state where the measurement environment is filled with a gas that hardly absorbs radiation in the vacuum ultraviolet wavelength region. A vacuum ultraviolet spectroscopic measurement device characterized in that an optical member is installed.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2002000096A JP2003202266A (en) | 2002-01-04 | 2002-01-04 | Vacuum ultraviolet spectral measuring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2002000096A JP2003202266A (en) | 2002-01-04 | 2002-01-04 | Vacuum ultraviolet spectral measuring device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2003202266A true JP2003202266A (en) | 2003-07-18 |
Family
ID=27640601
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2002000096A Pending JP2003202266A (en) | 2002-01-04 | 2002-01-04 | Vacuum ultraviolet spectral measuring device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2003202266A (en) |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007506976A (en) * | 2003-09-23 | 2007-03-22 | メトロソル・インコーポレーテツド | Standard alignment type vacuum ultraviolet reflectometer |
| US7948631B2 (en) | 2008-02-28 | 2011-05-24 | Jordan Valley Semiconductors Ltd. | Method and apparatus for using multiple relative reflectance measurements to determine properties of a sample using vacuum ultra violet wavelengths |
| US7990549B2 (en) | 2006-11-30 | 2011-08-02 | Jordan Valley Semiconductors Ltd. | Method and apparatus for optically measuring periodic structures using orthogonal azimuthal sample orientation |
| US8119991B2 (en) | 2004-08-11 | 2012-02-21 | Jordan Valley Semiconductors Ltd. | Method and apparatus for accurate calibration of VUV reflectometer |
| CN103148939A (en) * | 2013-02-28 | 2013-06-12 | 北京振兴计量测试研究所 | Ultraviolet spectrum measurement method and system for inhibiting second order spectrum |
| US8564780B2 (en) | 2003-01-16 | 2013-10-22 | Jordan Valley Semiconductors Ltd. | Method and system for using reflectometry below deep ultra-violet (DUV) wavelengths for measuring properties of diffracting or scattering structures on substrate work pieces |
| US8565379B2 (en) | 2011-03-14 | 2013-10-22 | Jordan Valley Semiconductors Ltd. | Combining X-ray and VUV analysis of thin film layers |
| US8867041B2 (en) | 2011-01-18 | 2014-10-21 | Jordan Valley Semiconductor Ltd | Optical vacuum ultra-violet wavelength nanoimprint metrology |
| JP2015532433A (en) * | 2012-10-18 | 2015-11-09 | ブイユーブイ・アナリティクス・インコーポレイテッドＶＵＶ Ａｎａｌｙｔｉｃｓ，Ｉｎｃ． | Vacuum ultraviolet absorption spectroscopy system and method |
| US10677767B2 (en) | 2018-06-12 | 2020-06-09 | Vuv Analytics, Inc. | Vacuum ultraviolet absorption spectroscopy system and method |
| CN113820293A (en) * | 2020-06-19 | 2021-12-21 | 核工业理化工程研究院 | Low-temperature gas spectrum measuring device and using method thereof |
-
2002
- 2002-01-04 JP JP2002000096A patent/JP2003202266A/en active Pending
Cited By (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8014000B2 (en) | 2003-01-16 | 2011-09-06 | Jordan Valley Semiconductors Ltd. | Broad band referencing reflectometer |
| US8054453B2 (en) | 2003-01-16 | 2011-11-08 | Jordan Valley Semiconductors Ltd. | Broad band referencing reflectometer |
| US8564780B2 (en) | 2003-01-16 | 2013-10-22 | Jordan Valley Semiconductors Ltd. | Method and system for using reflectometry below deep ultra-violet (DUV) wavelengths for measuring properties of diffracting or scattering structures on substrate work pieces |
| JP2007506976A (en) * | 2003-09-23 | 2007-03-22 | メトロソル・インコーポレーテツド | Standard alignment type vacuum ultraviolet reflectometer |
| US8119991B2 (en) | 2004-08-11 | 2012-02-21 | Jordan Valley Semiconductors Ltd. | Method and apparatus for accurate calibration of VUV reflectometer |
| US7990549B2 (en) | 2006-11-30 | 2011-08-02 | Jordan Valley Semiconductors Ltd. | Method and apparatus for optically measuring periodic structures using orthogonal azimuthal sample orientation |
| US7948631B2 (en) | 2008-02-28 | 2011-05-24 | Jordan Valley Semiconductors Ltd. | Method and apparatus for using multiple relative reflectance measurements to determine properties of a sample using vacuum ultra violet wavelengths |
| US8867041B2 (en) | 2011-01-18 | 2014-10-21 | Jordan Valley Semiconductor Ltd | Optical vacuum ultra-violet wavelength nanoimprint metrology |
| US8565379B2 (en) | 2011-03-14 | 2013-10-22 | Jordan Valley Semiconductors Ltd. | Combining X-ray and VUV analysis of thin film layers |
| JP2015532433A (en) * | 2012-10-18 | 2015-11-09 | ブイユーブイ・アナリティクス・インコーポレイテッドＶＵＶ Ａｎａｌｙｔｉｃｓ，Ｉｎｃ． | Vacuum ultraviolet absorption spectroscopy system and method |
| US9465015B2 (en) | 2012-10-18 | 2016-10-11 | Vuv Analytics, Inc. | Vacuum ultraviolet absorption spectroscopy system and method |
| US9696286B2 (en) | 2012-10-18 | 2017-07-04 | Vuv Analytics, Inc. | Vacuum ultraviolet absorption spectroscopy system and method |
| US9891197B2 (en) | 2012-10-18 | 2018-02-13 | Vuv Analytics, Inc. | Vacuum ultraviolet absorption spectroscopy system and method |
| US9976996B2 (en) | 2012-10-18 | 2018-05-22 | Vuv Analytics, Inc. | Vacuum ultraviolet absorption spectroscopy system and method |
| US10338040B2 (en) | 2012-10-18 | 2019-07-02 | Vuv Analytics, Inc. | Vacuum ultraviolet absorption spectroscopy system and method |
| US10641749B2 (en) | 2012-10-18 | 2020-05-05 | Vuv Analytics, Inc. | Vacuum ultraviolet absorption spectroscopy system and method |
| CN103148939A (en) * | 2013-02-28 | 2013-06-12 | 北京振兴计量测试研究所 | Ultraviolet spectrum measurement method and system for inhibiting second order spectrum |
| US10677767B2 (en) | 2018-06-12 | 2020-06-09 | Vuv Analytics, Inc. | Vacuum ultraviolet absorption spectroscopy system and method |
| CN113820293A (en) * | 2020-06-19 | 2021-12-21 | 核工业理化工程研究院 | Low-temperature gas spectrum measuring device and using method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR101279911B1 (en) | Calibration of a radiometric optical monitoring system used for fault detection and process monitoring | |
| CA2904850C (en) | Analytes monitoring by differential swept wavelength absorption spectroscopy methods | |
| US6160832A (en) | Method and apparatus for wavelength calibration | |
| JP3306079B2 (en) | Optical analyzer and calibration method thereof | |
| JP2003214958A (en) | Wavelength detecting device, laser device, and wavelength detecting method | |
| US10890484B2 (en) | Wavelength measuring device | |
| JP2003202266A (en) | Vacuum ultraviolet spectral measuring device | |
| Hausmann et al. | Detection of tropospheric OH radicals by long‐path differential‐optical‐absorption spectroscopy: Experimental setup, accuracy, and precision | |
| Ruth et al. | Broadband cavity-enhanced absorption spectroscopy with incoherent light | |
| KR101709820B1 (en) | Metrology module for laser system | |
| Hoch et al. | An instrument for measurements of BrO with LED-based cavity-enhanced differential optical absorption spectroscopy | |
| KR20010110748A (en) | Analysis apparatus | |
| KR20010021565A (en) | Method for calibration of a spectroscopic sensor | |
| KR20020030736A (en) | Energy monitor for molecular fluorine laser | |
| US9772226B2 (en) | Referenced and stabilized optical measurement system | |
| US5991032A (en) | Contaminant identification and concentration determination by monitoring the intensity of the output of an intracavity laser | |
| JP2000106463A (en) | Wavelength calibration method and system for excimer laser | |
| JP2003214949A (en) | Monitoring device and ultraviolet laser device | |
| US6456361B1 (en) | Method and instrument for measuring vacuum ultraviolet light beam, method of producing device and optical exposure apparatus | |
| JP2000266605A (en) | Wavelength measuring device for ultraviolet laser | |
| JP5483161B2 (en) | Zero / span adjustment method for laser gas analyzer | |
| JP4699640B2 (en) | Wavelength measuring equipment for vacuum ultraviolet laser equipment | |
| JP2000088705A (en) | Device for monitoring light of excimer laser | |
| US7646951B2 (en) | Apparatus for manufacturing optical fiber Bragg grating, optical fiber, and mid-infrared optical fiber laser | |
| KR20060066561A (en) | Light absorbance cell and parallelyzer for the absolute measurement of ozone in uv absorption spectrophotometer |