High quality and high aspect ratio processing of multilayer structures with dissimilar material properties by UV laser microjet

Backfilling contributes to the improvement of ground stability and reduction of ore dilution in underground mines. A critical issue for backfilled stope design is the required strength for the fill material. A practical solution to address this question was proposed by Mitchell and co-workers for stopes with an exposed face and a high aspect ratio (height H over width B). However, this solution is not directly applicable to stopes with a relatively low aspect ratio (H/B). Its application is also restricted by additional limitations on the strength along the fill–rock interfaces and the load applied on top of the backfill. In this note, the model proposed by Mitchell and co-workers is modified to provide an estimate of the required strength of backfill for various geometries, material properties, and surface loads. The modified Mitchell (MM) solution is validated against experimental results. Sample calculations with the MM solution are also presented and discussed.

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High-aspect-ratio Microdrilling with UV Laser Ablation V.

Journal of the Japan Society for Precision Engineering ◽

10.2493/jjspe.77.1135 ◽

2011 ◽

Vol 77 (12) ◽

pp. 1135-1139

Author(s):

Hirofumi HIDAI ◽

Sho ITOH ◽

Hitoshi TOKURA

Keyword(s):

Laser Ablation ◽

Aspect Ratio ◽

High Aspect Ratio ◽

Uv Laser

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The Accuracy of Micro-molds Produced by a UV Laser Induced Polymerization

Journal of Engineering for Industry ◽

10.1115/1.2901954 ◽

1994 ◽

Vol 116 (3) ◽

pp. 370-376 ◽

Cited By ~ 6

Author(s):

K. Yamaguchi ◽

T. Nakamoto ◽

P. A. Abbay ◽

S. Mibu

Keyword(s):

Thin Films ◽

Aspect Ratio ◽

Laser Beam ◽

High Aspect Ratio ◽

Research Work ◽

Practical Method ◽

High Accuracy ◽

Uv Laser ◽

Ultraviolet Laser ◽

Absorption Of Light

This research work deals with the development of a simple and practical method for manufacturing metallic micromachine parts on the order of 0.01–1.0 mm in size. In this method, an ultraviolet laser beam is irradiated onto the surface of a liquid photopolymer material through a mask. The irradiated pattern is then developed to produce a solidified photopolymer mold. Finally, the metallic part is made by an electroforming process. This paper deals with the first process, the making of the photopolymer mold. At first, the accuracy of the mold is estimated by applying the theories of diffraction and absorption of light. Next, the accuracy is examined experimentally. The results show an accuracy of ± 1 μm can be obtained when a proximity transfer of 10 μm between the mask and the photopolymer surface is used. By stacking thin films, thick and high aspect ratio molds with a reasonably high accuracy are made.

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Deep-UV, Light-Assisted, Wet Etching of Compound Semiconductors

MRS Proceedings ◽

10.1557/proc-29-161 ◽

1983 ◽

Vol 29 ◽

Cited By ~ 1

Author(s):

D. V. Podlesnik ◽

H. H. Gilgen ◽

R. M. Osgood

Keyword(s):

Aspect Ratio ◽

Visible Light ◽

High Aspect Ratio ◽

Laser Light ◽

Uv Light ◽

Compound Semiconductors ◽

Wet Etching ◽

Uv Laser ◽

Via Holes ◽

Deep Uv

ABSTRACTDeep-UV, laser-light-assisted, wet etching of compound semiconductors is reported. As ccmpared to results with visible light, the etching rates per unit power density in the ultraviolet are considerably faster; a factor of >30 is seen under typical conditions. A correlation between the UV absorption in different etching solutions and the light-enhanced etching rates is examined. Gratings with 100-nm resolution have been produced and high-aspect-ratio via-holes have been etched.

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