INSPECTION DEVICE

• Main Authors: TAKAHASHI NORIJI, HAYATA YASUNARI, SHINTANI ATSUKO, KOYAMA HIKARI
• Format: Patent
• Language: English; Japanese
• Published: 19.11.2020
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS; ELECTRICITY

To provide an inspection device that can estimate the amount of defocus from one image or a very small number of images.SOLUTION: An inspection device includes a charged particle beam source 401 that emits a charged particle beam, a charged particle optical system including a plurality of lenses 403 and 406 that focus the charged particle beam on a sample, a detector 410 that detects secondary charged particles emitted by the interaction between the charged particle beam and the sample, and an arithmetic unit 412 that executes autofocus every time the field of view of the charged particle optical system moves through a plurality of inspection spots. The arithmetic unit 412 irradiates the sample with a charged particle beam under an optical condition in which the charged particle optical system introduces astigmatism of a predetermined specification into the optical condition for observing a pattern, and the detector detects the secondary charged particles, and executes autofocus using an image formed from an output signal.SELECTED DRAWING: Figure 5 【課題】１枚または極少数の画像からデフォーカス量を推定可能な検査装置を提供する。【解決手段】荷電粒子線を放出する荷電粒子線源４０１と、荷電粒子線を試料上に集束させる複数のレンズ４０３，４０６とを含む荷電粒子光学系と、荷電粒子線と試料との相互作用により放出される２次荷電粒子を検出する検出器４１０と、荷電粒子光学系の視野が複数の検査スポットを移動するごとにオートフォーカスを実行する演算部４１２とを有し、演算部４１２は、荷電粒子光学系がパターンを観察するための光学条件に所定仕様の非点収差を導入した光学条件で荷電粒子線を試料に照射し、検出器が２次荷電粒子を検出して出力した信号から形成した画像を用いて、オートフォーカスを実行する。【選択図】図５