发明名称 |
PARTICLE-OPTICAL APPARATUS COMPRISING A DETECTOR FOR SECONDARY ELECTRONS |
摘要 |
The focusing device <u>8</u> for the primary beam in a scanning electron microscope (SEM) consists in known manner of a combination of a magnetic gap lens (34) and a monopole lens (38). The secondary electrons released from the specimen are detected in accordance with the invention by a detector whose deflection unit <u>52</u>, or the actual detector (64, 66), is arranged in a field-free space between the gap lens and the monopole lens. This space is rendered field-free by a screening plate (44) arranged underneath the gap lens. In order to achieve a high detector efficiency and a large field of vision, the pole tip of the focusing device <u>8</u> is provided with an attraction electrode (42) whose potential is higher than that of the specimen. |
申请公布号 |
WO9527994(A2) |
申请公布日期 |
1995.10.19 |
申请号 |
WO1995IB00232 |
申请日期 |
1995.04.04 |
申请人 |
PHILIPS ELECTRONICS N.V.;PHILIPS NORDEN AB |
发明人 |
VAN DER MAST, KAREL, DIEDERICK;KRUIT, PIETER;TROOST, KARS, ZEGER;HENSTRA, ALEXANDER |
分类号 |
H01J37/141;H01J37/244;H01J37/28 |
主分类号 |
H01J37/141 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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