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

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.

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

1999 ◽  
Vol 4 (S1) ◽  
pp. 69-74
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

We 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.

Characterization of TMR Head Durability against Lapping Based on Magnetic Performance

2012 ◽  
Vol 523-524 ◽  
pp. 961-966
Author(s):  
Hideaki Tanaka ◽  
Yukio Maeda
Keyword(s):  
Ion Beam ◽  
Hysteresis Loops ◽  
Areal Density ◽  
Noise Spectrum ◽  
Crystallographic Analysis ◽  
Magnetic Characteristics ◽  
Ion Beam Etching ◽  
Verification Method ◽  
Magnetic Performance

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.

scholarly journals Focused Ion Beam Etching of GaN

1999 ◽  
Vol 4 (S1) ◽  
pp. 769-774 ◽  
Author(s):  
C. Flierl ◽  
I.H. White ◽  
M. Kuball ◽  
P.J. Heard ◽  
G.C. Allen ◽  
...  
Keyword(s):  
Focused Ion Beam ◽  
Ion Beam ◽  
Etching Rate ◽  
Side Wall ◽  
Device Fabrication ◽  
Direct Write ◽  
Ion Beam Etching ◽  
Etched Surface ◽  
A Current ◽  
Established Technique

We have investigated the use of focused ion beam (FIB) etching for the fabrication of GaN-based devices. Although work has shown that conventional reactive ion etching (RIE) is in most cases appropriate for the GaN device fabrication, the direct write facility of FIB etching – a well-established technique for optical mask repair and for IC failure analysis and repair – without the requirement for depositing an etch mask is invaluable. A gallium ion beam of about 20nm diameter was used to sputter GaN material. The etching rate depends linearly on the ion dose per area with a slope of 3.5 × 10−4 μm3/pC. At a current of 3nA, for example, this corresponds to an each rate of 1.05 μm3/s. Good etching qualities have been achieved with a side wall roughness significantly below 0.1 μm. Change in the roughness of the etched surface plane stay below 8nm.

Characterization of Ar+ based Ion Beam Etching of GaN

2006 ◽  
Author(s):  
Rafal Dylewicz ◽  
Sergiusz Patela ◽  
Regina Paszkiewicz ◽  
Marek Tlaczala ◽  
Zbigniew Ryszka
Keyword(s):  
Ion Beam ◽  
Ion Beam Etching

Ion beam etching and surface characterization of indium phosphide

1986 ◽  
Vol 48 (19) ◽  
pp. 1285-1287 ◽  
Author(s):  
N. Bouadma ◽  
P. Devoldere ◽  
B. Jusserand ◽  
P. Ossart
Keyword(s):  
Indium Phosphide ◽  
Surface Characterization ◽  
Ion Beam ◽  
Ion Beam Etching

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

2019 ◽  
Vol 27 (8) ◽  
pp. 10826 ◽  
Author(s):  
Yaoyu Zhong ◽  
Feng Shi ◽  
Ye Tian ◽  
Yifan Dai ◽  
Ci Song ◽  
...  
Keyword(s):  
Ion Beam ◽  
Fused Silica ◽  
Ion Beam Etching ◽  
Near Surface ◽  
Damage Precursor

Ion Beam Etching of Biological Material in the Scanning Electron Microscope

1969 ◽  
Vol 27 ◽  
pp. 10-11
Author(s):  
Patrick Echlin ◽  
David Kynaston ◽  
Paul M. Knights
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Biological Material ◽  
Ion Beam ◽  
Ion Source ◽  
Ion Beam Etching ◽  
Dynamic Experiments ◽  
First Time ◽  
Scanning Electron

An ion source has been designed to operate in the chamber of the Stereoscan scanning electron microscope and provides facilities for etching specimens in situ. The source is a demountable cold cathode discharge type requiring only simple control.The ion beam described above has been used to progressively etch away hard or resilient biological material. This is the first time that ion beam etching of botanical specimens has been followed inside the scanning microscope, and marks the beginning of a range of dynamic experiments using this form of instrumentation.

Sign in / Sign up

Export Citation Format

Share Document