Patent ID: 8283642

Claim:
An ion beam sample preparation apparatus comprising: a) a tilting ion beam irradiating means disposed in a vacuum chamber and directing an ion beam toward a shield, characterized in that said tilting ion beam irradiating means projects an ion beam along a central ion beam axis, the direction of said central ion beam axis having a tilt angle with respect to said shield; b) a tilt drive operably coupled to said tilting ion beam irradiating means and configured to move the direction of said central ion beam axis between at least two different tilt angles; c) a shield retention stage disposed in the vacuum chamber; said shield retention stage comprising: i) a first datum feature; ii) a second datum feature; iii) a shield retention means having at least a shield releasing position and a shield retaining position; d) the shield having at least a rigid planar portion, removably and replaceably held in said shield retention stage, said shield further comprising: i) a proximal sample surface configured to durably adhere the sample to the shield; ii) a first shielding surface disposed in the path of the ion beam and positioned to shield a portion of the ion beam directed at the sample when said shield is held in the shield retaining position of the shield retention means; iii) a third datum feature formed integrally with said shield, wherein said shield retention means in said shield retaining position urges said third datum feature to abut said first datum feature; and, iv) a fourth datum feature formed integrally with said shield, wherein said shield retention means in said shield retaining position urges said fourth datum feature to abut said second datum feature.