Patent ID: 7241993

Claim:
An inspection apparatus for inspecting an object to be inspected by irradiating either of charged particles or electromagnetic waves onto said object to be inspected, said apparatus comprising: a mini-environment chamber for supplying a clean gas as a laminar downflow to said object to be inspected to prevent dust from contacting said object to be inspected, said mini-environment chamber includes a gas supply unit including a cleaning filter such as HEPA or ULPA filter for creating said clean gas, a pre-aligner for aligning the orientation of said object to be inspected in a rotation direction about the axis of said object for rough alignment thereof; a main housing including working chamber for inspecting said object to be inspected, said chamber capable of being controlled to have a vacuum atmosphere said working chamber includes; a beam generating means for generating either of said charged particles or said electromagnetic waves as a beam; an electron optical system including an objective lens for guiding and irradiating said beam onto said object to be inspected held in said working chamber, detecting secondary charged particles emanated from said object to be inspected by a secondary charged particle detector and introducing said secondary charged particles to an image processing system; a stage device for operatively holding said object to be inspected so as to be movable with respect to said beam, wherein said stage device permits highly accurate alignment of said object to be inspected by comprising a holder within said working chamber which holds said object in the x-direction, y-direction with respect to said beam, and in the direction about the axis normal to the object supporting surface of said holder, a loader housing disposed between said mini-environment chamber and said main housing, said loader housing includes a first loading chamber and a second loading chamber; wherein said first loading chamber includes a rack for placing the object thereon, a shutter device for opening and closing a first door connecting said first loading chamber and said mini-environment chamber, and a second shutter device for opening and closing a second door connecting said first loading chamber and said second loading chamber, said first loading chamber is adapted to be controllable so as to have a vacuum atmosphere; wherein said second loading chamber includes an arm which is movable to said rack for receiving the object and transporting the object to said main housing, said second loading chamber being held in a high vacuum atmosphere; a vibration isolator for supporting said main housing and said loader housing thereon; and an electrode located in the proximity of the object which is irradiated with said beam, an electric charge detector for detecting an electric charge of said electrode, and a power source for generating a voltage to said electrode corresponding to the electric charge of said electrode for offsetting said electric charge of said electrode.