scholarly journals Perpendicular patterned media in an (Al[sub 0.9]Ga[sub 0.1])[sub 2]O[sub 3]/GaAs substrate for magnetic storage

1999 ◽  
Vol 17 (6) ◽  
pp. 3190 ◽  
Author(s):  
Joyce Wong ◽  
Axel Scherer ◽  
Mladen Barbic ◽  
Sheldon Schultz
Keyword(s):  
Gaas Substrate ◽  
Magnetic Storage ◽  
Patterned Media

A Magnetic Rotary Encoder for Patterned Media Lithography

2014 ◽  
Author(s):  
Shaomin Xiong ◽  
Yuan Wang ◽  
Xiang Zhang ◽  
David Bogy
Keyword(s):  
High Speed ◽  
New Technology ◽  
Hard Disk Drives ◽  
Magnetic Storage ◽  
Magnetic Islands ◽  
Bit Patterned Media ◽  
Patterned Media ◽  
Rotary Encoder ◽  
Digital Format ◽  
Field Programmable

Bit patterned media (BPM) is expected to enable the magnetic storage density in hard disk drives (HDDs) beyond 1 Tb/in2. BPM uses isolated magnetic islands to record the data information. However, the large volume fabrication of those patterned media disks at an affordable cost is a challenge for this new technology. A master template is the first step for patterned media fabrication. Using nano-imprint technology, the master template can be replicated to tens of thousands of pattern disks. A rotary electron beam lithography machine or plasmonic nanolithography machine is recommended to assist in the fabrication of the master template. In both systems, a high resolution encoder system for positioning in the rotary lithography machine is necessary. In this paper, a magnetic rotary encoder system is introduced. The encoder system can be operated at several thousand revolution per minute (RPM). The scale pitch is 90 nm which is one to two orders smaller than current optical encoders. The resolution is about 2.8 million counts per revolution (CPR). A flying magnetic head is used to retrieve the readback signal from the magnetic encoders. A field programmable gate array (FPGA) is implemented to finish the high speed signal processing and provide a digital format encoder signal to trigger the lithography machine at a rate of several Mega Hertz.

Fabrication of 6-nm-Sized Nanodot Arrays with 12 nm-Pitch along Guide Lines Using both Self-Assembling and Electron Beam-Drawing for 5 Tbit/in2 Magnetic Recording

2013 ◽  
Vol 596 ◽  
pp. 73-77
Author(s):  
Sumio Hosaka ◽  
Takashi Akahane ◽  
Miftakhul Huda Huda ◽  
Takuya Komori ◽  
Hui Zhang ◽  
...  
Keyword(s):  
Electron Beam ◽  
Magnetic Recording ◽  
Self Assembly ◽  
Magnetic Storage ◽  
Fusion Method ◽  
Patterned Media ◽  
Dimethyl Siloxane ◽  
Self Assembling ◽  
Nanodot Arrays ◽  
Guide Lines

A possibility to fabricate nanodot arrays with a dot size of <10 nm="" and="" a="" dot="" pitch="" of="" 12="" along="" guide="" lines="" has="" been="" studied="" for="" ultrahigh-density="" patterned="" media="" in="" magnetic="" recording="" this="" was="" by="" using="" self-assembling="" block="" copolymers="" polystyrene-poly="" dimethyl="" siloxane="" ps-pdms="" electron="" beam="" eb="" drawing="" with="" hydrogen="" silsesquioxane="" hsq="" negative="" resist="" their="" fusion="" method="" it="" demonstrated="" that="" the="" could="" possibly="" achieve="" 6-nm-sized="" nanodot="" arrays="" 10="" 4="" x="" sup="">2 using self-assembling with PS-PDMS of molecular weight 7000-1500 and EB-drawing for narrow guide lines. These results prove that the fusion method is required for achieving extremely small dot arrays as 5 Tbit/in2magnetic storage devices.Keywords: Nanodot, self-assembly, electron-beam drawing, graphoepitaxy, patterned media, magnetic recording.

Ion Projection Lithography for Nano Patterning

1999 ◽  
Vol 584 ◽  
Author(s):  
A. Heuberger ◽  
W. Bruenger
Keyword(s):  
Continuous Improvement ◽  
Magnetic Films ◽  
Magnetic Storage ◽  
Flow Process ◽  
Patterned Media ◽  
Projection Lithography ◽  
Stencil Mask ◽  
Fraunhofer Institute ◽  
Ion Projection Lithography ◽  
Nano Patterning

AbstractAs a result of continuous improvement of the resist process, the experimental ion projector in the Fraunhofer Institute in Berlin (manufactured by Ion Microfabrication Systems, IMS, Vienna) has been able to print 75 nm lines and spaces into 180 nm thick standard DUV resist UV II HS without pattern collapse. A new wafer flow process for more reliable open stencil mask making was developed by IMS –Chips, Stuttgart (Germany), based on SOT wafers. Resistless direct surface modification by He and Xe ions has been tested on metallic and magnetic films in the Berlin projector. This method opens up a new possibility for the production of patterned media for future magnetic storage disks.

Fabrication of patterned media for high density magnetic storage

2000 ◽  
Vol 53 (1-4) ◽  
pp. 67-67 ◽  
Author(s):  
C ROSS ◽  
H SMITH ◽  
T SAVAS ◽  
M SCHATTENBURG ◽  
M FARHOUD ◽  
...  
Keyword(s):  
High Density ◽  
Magnetic Storage ◽  
Patterned Media

Fabrication of patterned media for high density magnetic storage

1999 ◽  
Vol 17 (6) ◽  
pp. 3168 ◽  
Author(s):  
C. A. Ross ◽  
Henry I. Smith ◽  
T. Savas ◽  
M. Schattenburg ◽  
M. Farhoud ◽  
...  
Keyword(s):  
High Density ◽  
Magnetic Storage ◽  
Patterned Media

Two-Bit-Per-Dot Patterned Media for Magnetic Storage

2011 ◽  
Vol 2 ◽  
pp. 4500104-4500104 ◽  
Author(s):  
Jérôme Moritz ◽  
Christophe Arm ◽  
Giovanni Vinai ◽  
Eric Gautier ◽  
Stéphane Auffret ◽  
...  
Keyword(s):  
Magnetic Storage ◽  
Patterned Media

scholarly journals Modulation Code for Reducing Intertrack Interference on Staggered Bit-Patterned Media Recording

2020 ◽  
Vol 10 (15) ◽  
pp. 5295 ◽  
Author(s):  
Seongkwon Jeong ◽  
Jaejin Lee
Keyword(s):  
Storage System ◽  
Areal Density ◽  
Magnetic Storage ◽  
Two Dimensional ◽  
Bit Patterned Media ◽  
Patterned Media ◽  
Cross Track ◽  
Modulation Code ◽  
Intertrack Interference

A bit-patterned media recording (BPMR) system is a type of ultrahigh-capacity magnetic storage system that can extend to an areal density of 1 terabit per square inch or higher. However, because the space between islands in the down- and cross-track directions is reduced to extend the areal density, the effect of two-dimensional interference is increased. However, using a staggered array, which is one of the possible island distributions for BPMR, helps to decrease intertrack interference. A 7/10 modulation code for a staggered BPMR is proposed to avoid the effect of two-dimensional interference and provide distance among nonidentical codewords for improving the correcting capability.

Cristal-growth dynamics of n-doped gaAs

1992 ◽  
Vol 50 (2) ◽  
pp. 1544-1545
Author(s):  
Pham V. Huong ◽  
Stéphanie Bouchet ◽  
Jean-Claude Launay
Keyword(s):  
Crystal Growth ◽  
Spatial Resolution ◽  
Epitaxial Layer ◽  
Outer Surface ◽  
Gaas Substrate ◽  
Structural Modification ◽  
Growth Dynamics ◽  
Argon Laser ◽  
High Anisotropy ◽  
Crystal Gaas

Microstructure of epitaxial layers of doped GaAs and its crystal growth dynamics on single crystal GaAs substrate were studied by Raman microspectroscopy with a Dilor OMARS instrument equipped with a 1024 photodiode multichannel detector and a ion-argon laser Spectra-Physics emitting at 514.5 nm.The spatial resolution of this technique, less than 1 μm2, allows the recording of Raman spectra at several spots in function of thickness, from the substrate to the outer deposit, including areas around the interface (Fig.l).The high anisotropy of the LO and TO Raman bands is indicative of the orientation of the epitaxial layer as well as of the structural modification in the deposit and in the substrate at the interface.With Sn doped, the epitaxial layer also presents plasmon in Raman scattering. This fact is already very well known, but we additionally observed that its frequency increases with the thickness of the deposit. For a sample with electron density 1020 cm-3, the plasmon L+ appears at 930 and 790 cm-1 near the outer surface.

Interfacial properties of GaSb/InAs superlattices

1993 ◽  
Vol 51 ◽  
pp. 826-827
Author(s):  
M. E. Twigg ◽  
B. R. Bennett ◽  
J. R. Waterman ◽  
J. L. Davis ◽  
B. V. Shanabrook ◽  
...  
Keyword(s):  
Gaas Substrate ◽  
Molecular Beam ◽  
Infrared Detector ◽  
Interfacial Properties ◽  
Ex Situ ◽  
X Ray Diffraction ◽  
Absorption Coefficients ◽  
X Ray ◽  
Short Period ◽  
High Optical Absorption

Recently, the GaSb/InAs superlattice system has received renewed attention. The interest stems from a model demonstrating that short period Ga1-xInxSb/InAs superlattices will have both a band gap less than 100 meV and high optical absorption coefficients, principal requirements for infrared detector applications. Because this superlattice system contains two species of cations and anions, it is possible to prepare either InSb-like or GaAs-like interfaces. As such, the system presents a unique opportunity to examine interfacial properties.We used molecular beam epitaxy (MBE) to prepare an extensive set of GaSb/InAs superlattices grown on an GaSb buffer, which, in turn had been grown on a (100) GaAs substrate. Through appropriate shutter sequences, the interfaces were directed to assume either an InSb-like or GaAs-like character. These superlattices were then studied with a variety of ex-situ probes such as x-ray diffraction and Raman spectroscopy. These probes confirmed that, indeed, predominantly InSb-like and GaAs-like interfaces had been achieved.

Structural properties of GaAs/InGaAs/GaAs (001) and InGaAs/GaAs (001) heterostructures and correlation with electronic properties

1990 ◽  
Vol 48 (4) ◽  
pp. 602-603
Author(s):  
J.M. Bonar ◽  
R. Hull ◽  
R. Malik ◽  
R. Ryan ◽  
J.F. Walker
Keyword(s):  
Band Gap ◽  
Electronic Properties ◽  
Gaas Substrate ◽  
Critical Thickness ◽  
Lattice Mismatch ◽  
Band Offset ◽  
Misfit Dislocations ◽  
Gaas Substrates ◽  
Gaas Structure ◽  
Low X

In this study we have examined a series of strained heteropeitaxial GaAs/InGaAs/GaAs and InGaAs/GaAs structures, both on (001) GaAs substrates. These heterostructures are potentially very interesting from a device standpoint because of improved band gap properties (InAs has a much smaller band gap than GaAs so there is a large band offset at the InGaAs/GaAs interface), and because of the much higher mobility of InAs. However, there is a 7.2% lattice mismatch between InAs and GaAs, so an InxGa1-xAs layer in a GaAs structure with even relatively low x will have a large amount of strain, and misfit dislocations are expected to form above some critical thickness. We attempt here to correlate the effect of misfit dislocations on the electronic properties of this material.The samples we examined consisted of 200Å InxGa1-xAs layered in a hetero-junction bipolar transistor (HBT) structure (InxGa1-xAs on top of a (001) GaAs buffer, followed by more GaAs, then a layer of AlGaAs and a GaAs cap), and a series consisting of a 200Å layer of InxGa1-xAs on a (001) GaAs substrate.

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