Patent ID: 8610090

Claim:
An ion beam shield for use in preparing a sample in an ion beam sample preparation apparatus, the ion beam sample preparation apparatus having: an ion beam irradiating means configured to produce an ion beam; and, a shield retention stage in which the shield retention stage comprises a first datum feature, a second datum feature, and a shield retention means having at least a shield releasing position and a shield retaining position, the shield comprising: a) a rigid planar portion configured to be removeably and replaceably held in the shield retention stage; b) a proximal sample surface configured to durably adhere the sample to the shield; c) 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; d) a third datum feature formed integrally with said shield and configured such that the shield retention means in the shield retaining position urges said third datum feature to abut said first datum feature; and, e) a fourth datum feature formed integrally with said shield and configured such that the shield retention means in said shield retaining position urges said fourth datum feature to abut said second datum feature.