Process Optimization for Cylindrical Single-Crystal Silicon Mirror with a Tilted Incident Ion Beam Figuring

Reliability is one of the most critical issues for designing practical MEMS devices. In particular, the fracture toughness of micro-sized MEMS elements is important, as micro/nano-sized flaws can act as a crack initiation sites to cause failure of such devices. Existing MEMS devices commonly use single crystal silicon. Fracture toughness testing upon micro-sized single crystal silicon was therefore carried out to examine whether a fracture toughness measurement technique, based upon the ASTM standard, is applicable to 1/1000th sized silicon specimens. Notched cantilever beam type specimens were prepared by focused ion beam machining. Two specimens types with different notch orientations were prepared. The notch plane/direction were (100)/[010], and (110)/[ ＿ ,110], respectively. Fracture toughness tests were carried out using a mechanical testing machine for micro-sized specimens. Fracture has been seen to occur in a brittle manner in both orientations. The provisional fracture toughness values (KQ) are 1.05MPam1/2 and 0.96MPam1/2, respectively. These values meet the micro-yielding criteria for plane strain fracture toughness values (KIC). Fracture toughness values for the orientations tested are of the same order as values in the literature. The results obtained in this investigation indicate that the fracture toughness measurement method used is applicable for micro-sized components of single crystal silicon in MEMS devices.

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Preparation of Thin Single Crystal Silicon Substrates for in situ Electron Microscope Studies

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100071041 ◽

1973 ◽

Vol 31 ◽

pp. 120-121

Author(s):

J. S. Maa ◽

J. I. Lee ◽

Thos. E. Hutchinson

Keyword(s):

Electron Microscope ◽

Single Crystal ◽

Ion Beam ◽

Single Crystal Silicon ◽

Thin Film Deposition ◽

Film Deposition ◽

Micro Milling ◽

Crystal Silicon ◽

Etching Technique

The in-situ electron microscope technique has been shown to be a powerful method for understanding the nucleation and growth of thin films formed both by vacuum vapor deposition and ion beam sputter-deposition. Single crystal silicon which has only been chosen as substrate for thin film deposition outside the electron microscope has now been prepared in a form suitable for in-situ deposition.The method of the preparation of thin silicon substrate is a combination of jet chemical etching and modified ion beam thinning. A specimen of thickness roughly 0.010 inch is first etched from both sides by the jet etching technique. After jet etching, it is transferred to the Commonwealth Scientific ion micro-milling instrument and bombarded from both sides with Argon ion beam. A pin hole occurs in the center of the specimen after about 30 minutes of ion bombardment.

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The tensile effect on crack formation in single crystal silicon irradiated by intense pulsed ion beam

Nuclear Instruments and Methods in Physics Research Section B Beam Interactions with Materials and Atoms ◽

10.1016/j.nimb.2017.04.048 ◽

2017 ◽

Vol 409 ◽

pp. 277-281 ◽

Cited By ~ 2

Author(s):

Guoying Liang ◽

Jie Shen ◽

Jie Zhang ◽

Haowen Zhong ◽

Xiaojun Cui ◽

...

Keyword(s):

Single Crystal ◽

Crack Formation ◽

Ion Beam ◽

Single Crystal Silicon ◽

Crystal Silicon

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Research on the Surface Evolution of Single Crystal Silicon Mirror Contaminated by Metallic Elements during Elastic Jet Polishing Techniques

Materials ◽

10.3390/ma12071077 ◽

2019 ◽

Vol 12 (7) ◽

pp. 1077

Author(s):

Wanli Zhang ◽

Feng Shi ◽

Yifan Dai ◽

Yaoyu Zhong ◽

Ci Song ◽

...

Keyword(s):

Single Crystal ◽

Ion Beam ◽

Laser System ◽

Single Crystal Silicon ◽

Infrared Laser ◽

Metallic Elements ◽

Crystal Silicon ◽

Surface Evolution ◽

Metallic Contaminant ◽

Combined Technique

Metallic elements can contaminate single crystal silicon mirror during ion beam etching (IBE) and other postprocessing methods, which can affect the performance of components in an infrared laser system. In this work, scanning electron microscope (SEM) and atomic force microscope (AFM) were used to characterize the distribution of contaminant represented by aluminum (Al). After characterizing contaminated area, elastic jet polishing (EJP), EJP, and static alkaline etching (SAE) combined technique were used to process the mirror. The morphology and laser-induced absorption were measured. Results show that metallic elements can mix with silicon and generate bulges due to the sputtering effect. In addition, SAE and EJP combined technique can remove metallic contaminant and stabilize the surface quality. Research results can be a reference on conducting postprocessing technologies to improve laser damage resistance property of single crystal silicon mirror in infrared laser system.

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Transient Conductivity Measurements in Pulsed Ion Beam Melted Silicon

MRS Proceedings ◽

10.1557/proc-13-69 ◽

1983 ◽

Vol 13 ◽

Cited By ~ 1

Author(s):

R.M. Fastow ◽

J. Gyulai ◽

J.W. Mayer

Keyword(s):

Energy Density ◽

Single Crystal ◽

Proton Beam ◽

Linear Dependence ◽

Ion Beam ◽

Single Crystal Silicon ◽

Conductivity Measurements ◽

Crystal Silicon ◽

Measured Energy ◽

Good Agreement

ABSTRACTA pulsed proton beam, ˜200 ns in duration, has been used to melt and regrow single crystal silicon. The protons had an energy of 300 kev, yielding a measured energy density of 0.8–2.0 J/cm2. The method of transient conductivity has been used to determine the melt depths, melt durations, and regrowth velocities. The measured values for 2.0 J/cm2 were, respectively, 1.7 μm, 2 μsec, and 1.4 m/sec.Computer generated melt curves were compared to experiment with good agreement. The energy required to initiate melt was determined, and a linear dependence of melt depth with energy has been observed.

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