Detailed near-surface nanoscale damage precursor measurement and characterization of fused silica optics assisted by ion beam etching

Magnetic recording technologies are continuing to advance toward higher areal densities, driven by the availability of tunneling magnetoresistive (TMR) heads. However, high areal density heads require smaller physical dimensions, and this can render TMR heads more vulnerable to mechanical stresses generated during the lapping process. Although is important to verify the durability of TMR heads against lapping, it is very difficult to perform a crystallographic analysis of the affected layer because of the small dimensions involved. In this study, we attempted to establish an advanced TMR head verification method based on a magnetic performance analysis involving micro-Kerr hysteresis loops and the magnetic noise spectrum. We found that the magnetic performance changed when nanoscale scratches were removed from the lapped surface using ion beam etching. This indicates that the lapping process produces an affected layer which deteriorates the magnetic characteristics of the TMR head. A correlation was also found between the change in magnetic performance and the morphology of lapped surface.

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Fabrication of Phase Mask for Optical Fiber Grating

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.364-366.719 ◽

2007 ◽

Vol 364-366 ◽

pp. 719-723

Author(s):

Quan Liu ◽

Jian Hong Wu ◽

Ling Ling Fang ◽

Chao Ming Li

Keyword(s):

Diffraction Efficiency ◽

Ion Beam ◽

Fused Silica ◽

Phase Mask ◽

Fiber Grating ◽

Ion Beam Etching ◽

First Order ◽

Silica Substrate ◽

Order Diffraction ◽

A New Technique

A fused silica phase mask with the period of 1069nm, and ruled area 50×50mm2 has been fabricated by a new technique, which combines holographic-ion beam etching and reactive ion beam etching. This involves several steps: coating of substrates with controlled thickness of photoresist, formation of a grating mask by holograph interference exposure and development, and finally transferring etching of this mask into the fused silica substrate to form a permanent phase mask. Experimental measurements have shown that the zero order diffraction efficiency is less than 4% and the plus and minus first-order diffraction efficiency is more than 35%. Theoretical analysis has shown that these phase masks can be used for fabricating UV written Fiber Bragg Gratings.

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Characterization of InGaN/GaN-Based Multi-Quantum Well Distributed Feedback Lasers

MRS Proceedings ◽

10.1557/proc-537-g2.2 ◽

1998 ◽

Vol 537 ◽

Author(s):

Daniel Hofstetter ◽

Robert L. Thornton ◽

Linda T. Romano ◽

David P. Bour ◽

Michael Kneissl ◽

...

Keyword(s):

Ion Beam ◽

Device Fabrication ◽

Distributed Feedback ◽

Coupling Scheme ◽

Optically Pumped ◽

Ion Beam Etching ◽

Measurement Results ◽

Dfb Laser ◽

First Time

AbstractWe present a device fabrication technology and measurement results of both optically pumped and electrically injected InGaN/GaN-based distributed feedback (DFB) lasers operated at room temperature. For the optically pumped DFB laser, we demonstrate a complex coupling scheme for the first time, whereas the electrically injected device is based on normal index coupling. Threshold currents as low as 1. 1 A were observed in 500 μm long and 10 μm wide devices. The 3rd order grating providing feedback was defined holographically and dry-etched into the upper waveguiding layer by chemically-assisted ion beam etching. Even when operating these lasers considerably above threshold, a spectrally narrow emission (3.5 Å) at wavelengths around 400 nm was seen.

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Traceless mitigation of laser damage precursors on a fused silica surface by combining reactive ion beam etching with dynamic chemical etching

RSC Advances ◽

10.1039/c8ra06759g ◽

2018 ◽

Vol 8 (57) ◽

pp. 32417-32422

Author(s):

Laixi Sun ◽

Ting Shao ◽

Jianfeng Xu ◽

Xiangdong Zhou ◽

Xin Ye ◽

...

Keyword(s):

Chemical Etching ◽

Silica Surface ◽

Ion Beam ◽

Fused Silica ◽

Laser Damage ◽

Ion Beam Etching ◽

Reactive Ion Beam Etching

RIBE and DCE techniques can be combined to tracelessly mitigate laser damage precursors on a fused silica surface.

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Characterization of damage on GaAs in a reactive ion beam etching system using Schottky diodes

Journal of Vacuum Science & Technology B Microelectronics Processing and Phenomena ◽

10.1116/1.584314 ◽

1988 ◽

Vol 6 (3) ◽

pp. 876 ◽

Cited By ~ 10

Author(s):

S. Sugata

Keyword(s):

Ion Beam ◽

Schottky Diodes ◽

Ion Beam Etching ◽

Etching System ◽

Reactive Ion Beam Etching

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Characterization of Ar+ based Ion Beam Etching of GaN

2006 International Students and Young Scientists Workshop - Photonics and Microsystems ◽

10.1109/stysw.2006.343659 ◽

2006 ◽

Author(s):

Rafal Dylewicz ◽

Sergiusz Patela ◽

Regina Paszkiewicz ◽

Marek Tlaczala ◽

Zbigniew Ryszka

Keyword(s):

Ion Beam ◽

Ion Beam Etching

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Radiation Effects in Nonmetals: Amorphization, Phase Decomposition, and Nanoparticles

MRS Proceedings ◽

10.1557/proc-540-135 ◽

1998 ◽

Vol 540 ◽

Cited By ~ 4

Author(s):

A. Meldrum ◽

L.A. Boatner ◽

C.W. White ◽

D.O. Henderson

Keyword(s):

Ion Implantation ◽

Electron Irradiation ◽

Radiation Effects ◽

Elevated Temperatures ◽

Ion Irradiation ◽

Ion Beam ◽

Semiconductor Nanocrystals ◽

Heavy Ion ◽

Fused Silica ◽

Near Surface

AbstractRadiation effects in nonmetals have been studied for well over a century by geologists, mineralogists, physicists, and materials scientists. The present work focuses on recent results of investigations of the ion-beam-induced amorphization of the ABO4 compounds – including the orthophosphates (LnPO4; Ln = lanthanides) and the orthosilicates: zircon (ZrSiO4), hafnon (HfSiO4), and thorite (ThSiO4). In the case of the orthosilicates, heavy-ion irradiation at elevated temperatures causes the precipitation of a nanocrystalline metal oxide. Electron irradiation effects in these amorphized insulating ceramics can produce localized recrystallization on a nanometer scale. Similar electron irradiation techniques were used to nucleate monodispersed compound semiconductor nanocrystals formed by ion implantation of the elemental components into fused silica. Methods for the formation of novel structural relationships between embedded nanocrystals and their hosts have been developed and the results presented here demonstrate the general flexibility of ion implantation and irradiation techniques for producing unique near-surface microstructures in ion-implanted host materials.

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