Characteristics of silicon removal by fine focused gallium ion beam
Characteristics of silicon removal by fine focused gallium ion beam
复制标题
精细聚焦镓离子束除硅特性
DOI：
--
复制
发表时间：
1985
期刊：
影响因子：
--
通讯作者：
T. Miyauchi
中科院分区：
文献类型：
--
作者：
H. Yamaguchi;A. Shimase;S. Haraichi;T. Miyauchi
构建了一套30 kV精细聚焦离子束加工系统，其中从针状液态金属源引出的Ga离子束通过三极静电透镜聚焦成亚微米光斑，并通过八极偏转器偏转。工作阶段的真空率为10− 7-10− 8 Torr。通过消隐电极，加工区域可以被限制在由扫描离子显微镜显示器上的光标线确定的任何矩形区域内。对于0.3 μm直径的光斑，探针电流大于0.3nA，电流密度大于0.71A/cm ~ 2。在100 μm/s的扫描速度下，在0.1 μm厚的金膜上形成了0.2 μm宽的沟槽。通过重复扫描，在（100）Si晶片中产生凹槽，产生具有纵横比为8：1的非常尖锐的V形的横截面。在各种条件下以1.9×101 8 ion/cm 2的相同剂量进行二维扫描去除，导致非常不同的孔形状。以1 mm/s的扫描速度重复去除200次，产生均匀的浅孔形状，而以5 μm/s的扫描速度重复去除一次，产生倾斜的深孔形状。横截面的观察表明，该倾斜区域从孔的侧壁突出，通过溅射硅的再沉积形成。这些结果表明，在利用精细聚焦离子束去除中，再沉积过程的重要性。此外，两种扫描方法的不同结果似乎证明了在精细聚焦离子束加工的非线性溅射效应。
A 30 kV fine focused ion beammachining system was constructed in which a Ga ion beam extracted from a needle‐type liquid metalsource is focused into a submicron spot by a three‐electrode electrostatic lens and deflected by an octapole deflector. Vacuum rate at the work stage is 10− 7–10− 8 Torr. With blanking electrodes, the machined area can be confined to any rectangular area determined by the cursol lines on the scanning ion microscopic display. Probe current is higher than 0.3 nA for a 0.3 μm diam spot and current density is over 0.71 A/cm2. At a scanning speed of 100 μm/s, grooves 0.2 μm wide are made in a gold film 0.1 μm thick. By scanning repeatedly, a groove is produced in a (100)Si wafer yielding a cross section having a very sharp V shape with an aspect ratio of 8:1. Two‐dimensional scanning removal is performed under various conditions at the same dose of 1.9×101 8 ion/cm2, resulting in very different hole shapes. Removal at a scanning speed of 1 mm/s with 200 repetitions produces a uniform shallow hole shape, while removal at 5 μm/s with one repetition results in an inclined deep hole shape. Observation of the cross section shows that this inclined area protrudes from the side wall of the hole, formed through the redeposition of sputtered silicon. These results show the importance of the redeposition process in removal utilizing fine focused ion beams. Also, the differing results of two scanning methods appear to demonstrate the nonlinear sputter effect in fine focused ion beammachining.