MEMS Materials and Fabrication Technology on Large Areas: The Example of an X-ray Imager

2000 ◽  
Vol 657 ◽  
Author(s):  
J.H. Daniel ◽  
B. Krusor ◽  
R. Lau ◽  
J.P. Lu ◽  
Y. Wang ◽  
...  
Keyword(s):  
Crystalline Silicon ◽  
Image Sensor ◽  
Large Area ◽  
Interlayer Dielectric ◽  
X Ray ◽  
Glass Substrates ◽  
Potential Applications ◽  
Mems Technology ◽  
Thick Photoresist ◽  
Silicon Based

ABSTRACTMicromachining has potential applications for large area image sensors and displays, but conventional MEMS technology, based on crystalline silicon wafers cannot be used. Instead, large area devices use deposited films on glass substrates. This presents many challenges for MEMS, both as regards materials for micro-machined structures and the integration with large area electronic devices. We are exploring the novel thick photoresist SU-8, as well as plating techniques for the fabrication of large area MEMS. As an example of its application, we have applied this MEMS technology to improve the performance of an amorphous silicon based image sensor array. SU-8 is explored as the structural material for the X-ray conversion screen and as a thick interlayer dielectric for the thin film readout electronics of the imager.

Novel large-area MIS-type x-ray image sensor for digital radiography

1998 ◽  
Author(s):  
Toshio Kameshima ◽  
Noriyuki Kaifu ◽  
Eiichi Takami ◽  
Masakazu Morishita ◽  
Tatsuya Yamazaki
Keyword(s):  
Digital Radiography ◽  
Image Sensor ◽  
Large Area ◽  
X Ray

Low noise, large area CMOS x-ray image sensor for C.T. application

2004 ◽  
Author(s):  
A. Kemna ◽  
W. Brockherde ◽  
B. Hosticka ◽  
E. Ozkan ◽  
F. Morales-Serrano ◽  
...  
Keyword(s):  
Image Sensor ◽  
Low Noise ◽  
Large Area ◽  
X Ray

New large-area x-ray image sensor

1998 ◽  
Author(s):  
Donald R. Ouimette ◽  
Sol Nudelman ◽  
Richard S. Aikens
Keyword(s):  
Image Sensor ◽  
Large Area ◽  
X Ray ◽  
Area X

Potential Applications of Poly-Silicon as an Electronic-Device Material

1981 ◽  
Vol 5 ◽  
Author(s):  
Dirk J. Bartelink
Keyword(s):  
Electronic Material ◽  
Grain Boundaries ◽  
Electronic Device ◽  
Crystalline Silicon ◽  
Ground Plane ◽  
Current Trend ◽  
Active Material ◽  
Flat Panel Display ◽  
Large Area ◽  
Potential Applications

ABSTRACTPoly-crystalline silicon can be regarded as a true electronic material if good p-n junctions can be made in it or if its state of depletion can be altered by reasonable gate voltages. The degree of perfection with which it must exhibit these electronic-material properties depends on whether the application is as a technology in VLSI (or other bulk-Si substrate use) where devices with bulk-crystalline properties are available or as the principal active material in Large Area Integration (LAI), such as flat-panel display addressing circuits, where the competition is much less demanding. The three main detrimental effects of grain boundaries on electronic-device function are the action of grain boundary traps as (1) extra charge centers, (2) lifetime killers, and (3) mobility-reducing scattering centers. The current trend in reducing or almost eliminating grain boundaries by laser recrystallization or lateral epitaxy has the effect of reducing the average number of traps. In terms of potential applications of the material, the improvement derived from these procedures must be balanced against other contraints placed on the overall structure. For example, the thickness and quality of the lower oxide (and interface) in these processes will determine whether an electronically active lower gate function is practical. Some currently envisioned applications include load devices in inverters either as resistors or as depletion transistors, common-gate staked CMOS structures, dual-channel MOSFET's, and other “vertical VLSI” applications. The systems-level topological advantages of stacked structures and the circuit-performance improvement provided by the ground plane in dielectrically isolated devices must also be balanced against the extra cost and yield loss of additional masking level complexity and design complication.

Large Grained, Low Defect Density Polycrystalline Silicon on Glass Substrates by Large-area Diode Laser Crystallisation

2012 ◽  
Vol 1426 ◽  
pp. 251-256 ◽  
Author(s):  
Bonne Eggleston ◽  
Sergey Varlamov ◽  
Jialiang Huang ◽  
Rhett Evans ◽  
Jonathon Dore ◽  
...  
Keyword(s):  
Diode Laser ◽  
Polycrystalline Silicon ◽  
Crystalline Silicon ◽  
Defect Density ◽  
Open Circuit ◽  
Large Area ◽  
High Quality ◽  
Glass Substrates ◽  
Silicon Thin Films ◽  
Open Circuit Voltages

ABSTRACTA new method to form high quality crystalline silicon thin films on cheap glass substrates is developed using a single pass of a line-focus cw diode laser in air. The laser process results in the formation of large high-quality crystals as they grow laterally in the scan direction – seeded by the previously crystallised region. Grains 10 μm in thickness, up to millimetres in length and hundreds of microns in width have been grown with virtually zero detectable intragrain defects. Another mode is found which results in much smaller crystals grown by partial melting. The dominant grain boundaries identified are Σ3 <111> 60° twins. Hall mobilities as high as 470 cm2/Vs have been recorded. A diffused emitter is used to create a p-n junction at the rear of the films which produces open-circuit voltages as high as 539 mV.

Large-area MEMS fabrication with thick SU-8 photoresist applied to an x-ray image sensor array

2000 ◽  
Author(s):  
Jurgen H. Daniel ◽  
Brent S. Krusor ◽  
Raj B. Apte ◽  
Robert A. Street ◽  
Adela Goredema ◽  
...  
Keyword(s):  
Sensor Array ◽  
Image Sensor ◽  
Large Area ◽  
X Ray ◽  
Mems Fabrication ◽  
Image Sensor Array

Flexible a-Si:H-based Image Sensors Fabricated by Digital Lithography

2007 ◽  
Vol 989 ◽  
Author(s):  
William S. Wong ◽  
TseNga Ng ◽  
Michael L. Chabinyc ◽  
Rene A. Lujan ◽  
Raj B. Apte ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Film Transistor ◽  
Sensor Arrays ◽  
Image Sensor ◽  
Image Sensors ◽  
X Ray ◽  
Ink Jet ◽  
Sensor Devices ◽  
Poly Ethylene ◽  
Silicon Based

AbstractAmorphous silicon-based x-ray image sensor arrays were fabricated on poly-ethylene naphthalate substrates at process temperatures below 180°C. Patterning of the thin-film transistor backplane was accomplished using ink-jet printed etch masks. The sensor devices were found to be comparable to high-temperature processed devices. The integration of the sensor stack, TFT array and PEN substrate resulted in a flexible x-ray image sensor with 180×180 pixels with 75 dpi resolution.

Optical properties and Limits of a Large-Area Periodic Nanophotonic Light Trapping Design for Polycrystalline Silicon Thin Film Solar Cells

2013 ◽  
Vol 1493 ◽  
pp. 59-64 ◽  
Author(s):  
Daniel Lockau ◽  
Tobias Sontheimer ◽  
Veit Preidel ◽  
Christiane Becker ◽  
Florian Ruske ◽  
...  
Keyword(s):  
Crystalline Silicon ◽  
Solid Phase ◽  
Light Trapping ◽  
Optical Design ◽  
Silicon Layer ◽  
Electron Beam Evaporation ◽  
Large Area ◽  
Silicon Thin Film ◽  
Material Loss ◽  
Glass Substrates

ABSTRACTRigorous finite element optical simulations have been used to examine the absorption of light in various crystalline silicon based, nanostructured solar cell architectures. The compared structures can all be produced on glass substrates using a periodically structured dielectric coating and a combination of electron-beam evaporation of silicon and subsequent solid phase crystallization. A required post-treatment by selective etching of non-compact silicon regions results in an absorber material loss. We show that by adequately tailoring the optical design around the processed silicon layer, the absorptance loss due to material removal can be completely overcome. The resulting silicon structure, which is an array of holes with non-vertical sidewalls, shows promising light path enhancement and features an even higher absorptance than the initial nanodome structure of the unetched absorber.

Preliminary Results on Large Area X-ray a-SiC:H Multilayer Detectors with Optically Addressed Readout

2007 ◽  
Vol 989 ◽  
Author(s):  
Manuela Vieira ◽  
Yuri Vygranenko ◽  
Miguel Fernandes ◽  
Paula Louro ◽  
Pedro Sanguino ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Charge Carrier ◽  
Carrier Transport ◽  
Image Sensor ◽  
Semiconductor Layer ◽  
Charge Carrier Transport ◽  
Large Area ◽  
X Ray ◽  
Switching Mode ◽  
Area X

AbstractThis paper investigates a feasibility of using a large area image sensor with an optically addressed readout for medical X-ray diagnostic imaging. A device prototype comprises a multilayer glass/ZnO:Al/p (a-SiC:H)/i (a-Si:H)/ n (a-SiC:H)/ i(a-Si:H)/p (a-SiC:H)/ a SiNx/ITO structure coupled to a scintillator layer. Here, the p-i-n-i-p structure works in both sensing and switching modes depending on the biasing conditions. A numerical simulation is used to optimize the semiconductor layer thicknesses in order to achieve a photocurrent matching between back-to-back diodes in switching mode. The charge carrier transport within the p-i-n-i-p structure is also analyzed under different electric and optical biasing conditions. A physical model supports the results.

Micro-electro-mechanical system fabrication technology applied to large area x-ray image sensor arrays

2001 ◽  
Vol 19 (4) ◽  
pp. 1219-1223 ◽  
Author(s):  
J. H. Daniel ◽  
B. Krusor ◽  
R. B. Apte ◽  
M. Mulato ◽  
K. Van Schuylenbergh ◽  
...  
Keyword(s):  
Mechanical System ◽  
Sensor Arrays ◽  
Micro Electro Mechanical System ◽  
Image Sensor ◽  
Fabrication Technology ◽  
Large Area ◽  
X Ray ◽  
Area X
Sign in / Sign up

Export Citation Format

Share Document