Dr. Jagmohan Bajaj Profile

Dr. Jagmohan Bajaj

Advisor to the Director at Army Research Laboratory

SPIE Involvement:

Conference Program Committee | Author

Publications (26)

Proceedings Article | 26 January 2018

Understanding fundamental limitations of materials to enable advanced design

Meredith Reed, Jagmohan Bajaj, Francesco Bertazzi, Enrico Bellotti, Jonathan Schuster, Philip Perconti

Proc. SPIE. 10540, Quantum Sensing and Nano Electronics and Photonics XV

KEYWORDS: Staring arrays, Long wavelength infrared, Semiconductors, Mercury cadmium telluride, Scattering, Semiconductor materials, Light scattering, Measurement devices, Superlattices, Instrument modeling

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Proceedings Article | 30 January 2017

Accelerating technology innovations by early understanding of fundamental and technology limitations of material synthesis and device operation

Jagmohan Bajaj, Roger DeWames, Jonathan Schuster, Meredith Reed, Philip Perconti, Enrico Bellotti

Proc. SPIE. 10111, Quantum Sensing and Nano Electronics and Photonics XIV

KEYWORDS: Long wavelength infrared, Semiconductors, Infrared sensors, Mercury cadmium telluride, Sensors, Semiconductor materials, Infrared technology, Stereolithography, Laser sintering, Instrument modeling

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Timely technology transition with minimal risk requires an understanding of fundamental and technology limitations of material synthesis, device operation and design controllable parameters. However, this knowledge-based approach requires substantial investment of resources in the Science and Technology (ST) stage of development. For low volume niche semiconductor technologies of Department of Defense (DoD) relevance, there is little drive for industry to expend their limited resources towards basic research simply because there is no significant return on investment. As a result, technology transition from ST to product development is often delayed, expensive and carries risks. The Army Research Laboratory (ARL) is addressing this problem by establishing a Center for Semiconductor Modeling of Materials and Devices (CSM) that brings together government, academia, and industry in a collaborative fashion to address research opportunities through its Open Campus initiative. This Center leverages combined core competencies of partner organizations, which include a broad knowledge base in modeling, and its validation; sharing of computational, characterization, materials growth and device processing resources; project continuity; and ‘extension of the bench’ via exchange of researchers between affiliated entities. A critical DoD technology is sensing in the infrared (IR) spectrum, where understanding of materials, devices and methods for sensing and processing IR information must continually improve to maintain superiority in combat. In this paper we focus on the historical evolution of IR technology and emphasize the need for understanding of material properties and device operation to accelerate innovation and shorten the cycle time, thereby ensuring timely transition of technology to product development and manufacturing. There are currently two competing IR technologies being pursued, namely the incumbent II-VI Hg1- xCdxTe technology and the III-V Type 2 Superlattices (SLs) technology. A goal of the CSM is to develop physics based models for Type 2 SLs with the capability to timely understand the knowledge gap between what is built and what is designed.

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Proceedings Article | 26 September 2016

Center for Semiconductor Materials and Device Modeling: expanding collaborative research opportunities between government, academia, and industry

Philip Perconti, Sarah Bedair, Jagmohan Bajaj, Jonathan Schuster, Meredith Reed

Proc. SPIE. 9933, Optical Sensing, Imaging, and Photon Counting: Nanostructured Devices and Applications 2016

KEYWORDS: Semiconductors, Infrared sensors, Sensors, Semiconductor materials, Diffusion, Computer simulations, 3D modeling, Modulation transfer functions, Laser sintering, Instrument modeling

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Proceedings Article | 13 February 2016

Sensors, nano-electronics and photonics for the Army of 2030 and beyond

Philip Perconti, W. C. Alberts, Jagmohan Bajaj, Jonathan Schuster, Meredith Reed

Proc. SPIE. 9755, Quantum Sensing and Nano Electronics and Photonics XIII

KEYWORDS: Semiconductors, Infrared sensors, Electronics, Sensors, Semiconductor materials, Quantum efficiency, Imaging spectroscopy, 3D modeling, Photonics, Infrared radiation, Infrared photography, Nanoelectronics, Performance modeling, Instrument modeling, Situational awareness sensors

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Proceedings Article | 7 May 2009

HgCdTe at Teledyne

W. Tennant, J. Arias, J. Bajaj

Proc. SPIE. 7298, Infrared Technology and Applications XXXV

KEYWORDS: Mid-IR, Short wave infrared radiation, Liquid phase epitaxy, Mercury cadmium telluride, Sensors, Silicon, Doping, Diodes, Metalorganic chemical vapor deposition, Semiconducting wafers

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Proceedings Article | 16 July 2008

Teledyne Imaging Sensors: silicon CMOS imaging technologies for x-ray, UV, visible, and near infrared

Yibin Bai, Jagmohan Bajaj, James Beletic, Mark Farris, Atul Joshi, Stefan Lauxtermann, Anders Petersen, George Williams

Proc. SPIE. 7021, High Energy, Optical, and Infrared Detectors for Astronomy III

KEYWORDS: Readout integrated circuits, Near infrared, CMOS sensors, Astronomy, Optical sensors, Imaging systems, Sensors, X-rays, Silicon, Quantum efficiency

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Proceedings Article | 8 June 2007

Comparison of type-II superlattice and HgCdTe infrared detector technologies

Jagmohan Bajaj, Gerry Sullivan, Don Lee, Ed Aifer, Manijeh Razeghi

Proc. SPIE. 6542, Infrared Technology and Applications XXXIII

KEYWORDS: Staring arrays, Infrared detectors, Long wavelength infrared, Mercury cadmium telluride, Sensors, Quantum efficiency, Detector arrays, Sensor performance, Superlattices, Laser sintering

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Proceedings Article | 25 August 2005

Recent progress of hybrid CMOS visible focal plane array technology

Y. Bai, M. Farris, A. Joshi, J. Hosack, J. Bajaj, J. Montroy

Proc. SPIE. 5902, Focal Plane Arrays for Space Telescopes II

KEYWORDS: Staring arrays, Readout integrated circuits, Imaging systems, Sensors, Silicon, Quantum efficiency, Detector arrays, Charge-coupled devices, CMOS technology, Temperature metrology

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Proceedings Article | 30 August 2004

Device analysis of MBE HgCdTe p-on-n photovoltaic detectors in 5- to 15-µm wavelength range

Priyalal Wijewarnasuriya, Nibir Dhar, Arvind D'Souza, Maryn Stapelbroek, Dennis Edwall, Jose Arias, Jagmohan Bajaj

Proc. SPIE. 5406, Infrared Technology and Applications XXX

KEYWORDS: Mid-IR, Mercury cadmium telluride, Cadmium, Sensors, Diffusion, Mercury, Quantum efficiency, Sensor performance, Photovoltaic detectors, Temperature metrology

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Proceedings Article | 12 January 2004

Hybrid CMOS focal plane array with extended UV and NIR response for space applications

Yibin Bai, Steve Bernd, Joseph Hosack, Mark Farris, John Montroy, Jagmohan Bajaj

Proc. SPIE. 5167, Focal Plane Arrays for Space Telescopes

KEYWORDS: Staring arrays, Near infrared, CMOS sensors, Imaging systems, Sensors, Ultraviolet radiation, Silicon, Quantum efficiency, Detector arrays, Charge-coupled devices

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Proceedings Article | 5 August 2002

Advanced imaging sensors at Rockwell Scientific Company

John Montroy, James Garnett, Scott Cabelli, Markus Loose, Atul Joshi, Gary Hughes, Lester Kozlowski, Allan Haas, Selmer Wong, Majid Zandian, Annie Chen, John Pasko, Mark Farris, Craig Cabelli, Donald Cooper, Jose Arias, Jagmohan Bajaj, Kadri Vural

Proc. SPIE. 4721, Infrared Detectors and Focal Plane Arrays VII

KEYWORDS: Mid-IR, CMOS sensors, Mercury cadmium telluride, Optical sensors, Imaging systems, Cameras, Sensors, Quantum efficiency, Image resolution, Infrared radiation

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Proceedings Article | 12 November 2001

Advances in large-area Hg1-xCdxTe photovoltaic detectors for remote sensing applications

Priyalal Wijewarnasuriya, Majid Zandian, Jamie Phillips, Dennis Edwall, Roger DeWames, Gernot Hildebrandt, Jagmohan Bajaj, Jose Arias, Arvind D'Souza, Fergus Moore

Proc. SPIE. 4454, Materials for Infrared Detectors

KEYWORDS: Long wavelength infrared, Mid-IR, Short wave infrared radiation, Photovoltaics, Mercury cadmium telluride, Sensors, Diffusion, Quantum efficiency, Semiconducting wafers, Photovoltaic detectors

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Proceedings Article | 10 October 2001

Cross-track infrared sounder FPA performance

Arvind D'Souza, Larry Dawson, Stacy Marsh, Richard Willis, Priyalal Wijewarnasuriya, Roger DeWames, Jose Arias, Jagmohan Bajaj, Gernot Hildebrandt, Fergus Moore

Proc. SPIE. 4369, Infrared Technology and Applications XXVII

KEYWORDS: Staring arrays, Long wavelength infrared, Mid-IR, Short wave infrared radiation, Photovoltaics, Sensors, Quantum efficiency, Amplifiers, Infrared radiation, Photovoltaic detectors

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Proceedings Article | 13 April 2000

State-of-the-art HgCdTe infrared devices

Jagmohan Bajaj

Proc. SPIE. 3948, Photodetectors: Materials and Devices V

KEYWORDS: Staring arrays, Readout integrated circuits, Mid-IR, Short wave infrared radiation, Mercury cadmium telluride, Sensors, Silicon, Quantum efficiency, Detector arrays, Infrared radiation

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Proceedings Article | 26 July 1999

HgCdTe detectors and FPAs for remote sensing applications

Arvind D'Souza, Larry Dawson, Dan Berger, Stewart Clark, Priyalal Wijewarnasuriya, Jagmohan Bajaj, Jose Arias, William Tennant, Lester Kozlowski, Kadri Vural

Proc. SPIE. 3698, Infrared Technology and Applications XXV

KEYWORDS: Staring arrays, Readout integrated circuits, Long wavelength infrared, Mid-IR, Short wave infrared radiation, Mercury cadmium telluride, Custom fabrication, Sensors, Remote sensing, Detector arrays

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Proceedings Article | 26 July 1999

2048x2048 HgCdTe focal plane arrays for astronomy applications

Kadri Vural, Lester Kozlowski, Donald Cooper, C. Chen, Gary Bostrup, Craig Cabelli, Jose Arias, Jagmohan Bajaj, Klaus-Werner Hodapp, Donald Hall, William Kleinhans, G. Price, J. Pinter

Proc. SPIE. 3698, Infrared Technology and Applications XXV

KEYWORDS: Staring arrays, Mid-IR, Short wave infrared radiation, Astronomy, Mercury cadmium telluride, Clocks, Sensors, Field effect transistors, Multiplexers, Semiconducting wafers

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Proceedings Article | 21 December 1998

HgCdTe multispectral infrared FPAs for remote sensing applications

Arvind D'Souza, Larry Dawson, Dan Berger, Arvel Markum, Jagmohan Bajaj, William Tennant, Jose Arias, Lester Kozlowski, Kadri Vural, Priyalal Wijewarnasuriya

Proc. SPIE. 3498, Sensors, Systems, and Next-Generation Satellites II

KEYWORDS: Staring arrays, Readout integrated circuits, Infrared sensors, Infrared imaging, Mid-IR, Short wave infrared radiation, Mercury cadmium telluride, Sensors, Detector arrays, Infrared radiation

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Infrared (IR) remote sensing imaging applications require high-performance Focal Plane Arrays (FPAs) operating in all ranges of the IR spectrum. Short wavelength (SWIR; 1 to 3 micrometer), middle wavelength (MWIR; 3 to 5 micrometer), mid- long wavelength (MLWIR; 6 to 8 micrometer), long wavelength (LWIR; 8 to 14 micrometer), and very long wavelength (VLWIR; greater than 14 micrometer). These diverse spectral bands require high performance detectors and Read Out Integrated Circuits (ROICs) to perform the multi-spectral mission requirements. Significant progress in the design and fabrication of HgCdTe detector arrays and Read Out Integrated Circuits (ROICs) over the past few years has led to the demonstration of high resolution, low noise and large format reliable FPAs. Hybrid FPAs have been measured and their performance parameters are presented. Focal Plane Array D* performance values have been obtained for a multitude of spectral ranges and configurations that include; (1) (lambda) c equals 1.8 micrometer, 12 X 256 arrays operating at 295 K with median D* approximately 1.4 X 1012 cm Hz1/2/W, (2) (lambda) c equals 2.4 micrometer, 12 X 256 arrays operating at 250 K with median D* equals 1.6 X 1012 cm Hz1/2/W, detectors used are grown by MBE on lattice matched CdZnTe, (3) PACE-1 detectors with (lambda) c equals 2.5 micrometer, 1024 X 1024 arrays operating at 115 K with peak D* of 2.3 X 1013 cm Hz1/2/W at a background flux (phi) b equals 1.2 X 1011 ph/cm2- s, (4) MBE HgCdTe on Silicon MWIR detectors have been fabricated and the detector RoA performance for (lambda) co approximately 5.0 micrometer is in the 106 to 107 ohm-cm2 range at 78 K. (5) MBE HgCdTe on CdZnTe detectors, ((lambda) c equals 15.8 micrometer at 65 K), 128 X 128 array operating at 40 K with peak D* of 2.76 X 1011 cm Hz1/2/W at a background flux (phi) b equals 8.0 X 1015 ph/cm2-s. High performance 640 X 480 arrays imaging in the MWIR band have been fabricated on CdZnTe and PACE-1 substrates. The performance of these and additional FPAs will be presented.

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Proceedings Article | 23 October 1997

Laser reflectance monitoring of the nucleation and growth of CdTe on basal plane sapphire substrates for focal plane arrays

A. Stafford, Stuart Irvine, K. Hess, Jagmohan Bajaj, R. Harper, P. Prete

Proc. SPIE. 3122, Infrared Spaceborne Remote Sensing V

KEYWORDS: Staring arrays, Scattering, Sensors, Laser scattering, Reflectivity, Reflectometry, Sapphire, Helium neon lasers, Feedback control, Temperature metrology

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The nucleation of CdTe onto basal plane sapphire and the subsequent growth of a CdTe buffer layer has been studied using in-situ laser reflectance (probe wavelength 633 nm, HeNe laser). The production of midwave infrared focal plane arrays requires the growth of typically 10 micrometer of CdTe (111)B buffer layer in order to grow out problems due to stacking faults, dislocation clusters and twinning. A-face and B-face growth of CdTe is seen to produce different reflectance 'signatures' within the first 6000 angstroms of growth, so enabling the early identification of problems with the growth process. Laser reflectance was also successfully demonstrated to predict the thickness of the buffer layer. Oscillations in the laser reflectance are attenuated due to absorption by the film at the probe wavelength used after approximately 6000 angstrom. However by the on-line calculation of the growth rate at every half wavelength oscillation, it is possible to extrapolate a film thickness for the total growth time. This extrapolated value is seen to be in good agreement with the thickness calculated ex-situ by beta-back scattering. The dependence on the buffer layer growth on the nucleation conditions was also investigated. The determination of whether the buffer layer grows A-face or B-face is seen to be more influenced by the II:VI ratio than the temperature during nucleation. For a nucleation temperature of 400 degrees Celsius, with a II:VI ratio of 6:1 the growth of the buffer layer is seen to be 100% A-face. As the II:VI ratio is increased the degree of A-face growth is seen to decline and the material becomes dominated by B-face growth. At a II:VI ratio of 60:1 the material is entirely B-face and predominantly untwinned. The difference in the two growth modes is manifested in the laser reflectance. Greater scattering of the laser light occurs during B-face growth due to the increased roughening compared to A-face growth. Consequently the reflectance signal in the B-face signature is seen to fall away more rapidly than is the case with A-face growth.

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SPIE Journal Paper | 1 May 1997

Micro-optic integration with focal plane arrays

M. Edward Motamedi, William Tennant, Haluk Sankur, Robert Melendes, Natalie Gluck, Sangtae Park, Jose Arias, Jagmohan Bajaj, John Pasko, William McLevige, Majid Zandian, Randolph Hall, Karla Steckbauer, Patti Richardson

OE Vol. 36 Issue 05

KEYWORDS: Microlens, Photoresist materials, Sensors, Diodes, Microlens array, Micro optics, Diffraction, Thin films, Staring arrays, Quantum efficiency

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Proceedings Article | 27 June 1996

MBE flexible manufacturing for HgCdTe focal plane arrays

J. Benson, John Dinan, James Waterman, Christopher Summers, Rudolph Benz, Brent Wagner, S. Pearson, Ashesh Parikh, John Jensen, Owen Wu, Rajesh Rajavel, G. Kamath, Karl Harris, Steven Jost, Jose Arias, Lester Kozlowski, Majid Zandian, Jagmohan Bajaj, Kadri Vural, Roger DeWames, Charles Cockrum, G. Venzor, Scott Johnson, H.-D. Shih, M. Bevan, J. Dodge, Art Simmons

Proc. SPIE. 2744, Infrared Technology and Applications XXII

KEYWORDS: Staring arrays, Liquid phase epitaxy, Mercury cadmium telluride, Sensors, Manufacturing, Detector arrays, Detector development, Infrared radiation, Semiconducting wafers, Heterojunctions

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Proceedings Article | 8 March 1996

FPAs and thin film binary optic microlens integration

M. Edward Motamedi, William Tennant, Robert Melendes, Natalie Gluck, Sangtae Park, Jose Arias, Jagmohan Bajaj, John Pasko, William McLevige, Majid Zandian, Randolph Hall, Karla Steckbauer, Patti Richardson, Donald Cooper

Proc. SPIE. 2687, Miniaturized Systems with Micro-Optics and Micromechanics

KEYWORDS: Thin films, Diffraction, Microlens array, Lenses, Sensors, Quantum efficiency, Photoresist materials, Microlens, Diodes, Photomasks

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The relatively large detector size of conventional focal plane arrays often acts as a limiting source of noise currents and requires these devices to run at undesirably low temperatures. To reduce the detector size without reducing the detector's quantum efficiency, we have developed efficient on-focal plane collection optics consisting of arrays of thin film binary optic microlenses on the back surface of hybrid detector array structures. P/n polarity photodiodes of an unusual `planar-mesa' geometry were fabricated in epitaxial HgCdTe deposited by molecular beam epitaxy on the `front' side of a CdZnTe substrate. Diffractive (8 - 16 phase level) Ge microlenses were deposited on 48 micrometers centers in a registered fashion (using an IR mask aligner and appropriate marks on the front surface of the CdZnTe) on the back side of the substrate using a lifting process. The lifting process circumvents some of the process limitations of the more conventional chemical etching method to diffractive microlens processing, allowing them to approach more closely their theoretical efficiency limit of > 95%. Prior to microlens deposition, but after diode fabrication, the test structures were flip- chip bonded or `hybridized' using indium interconnections to metallic strip lines which had been photolithographically deposited on sapphire dice (a process equally compatible with a silicon integrated circuit readout). After hybridization, the CdZnTe was thinned to equal the focal length of the lenses in the CdZnTe material. Optical characterization has demonstrated that the microlenses combined with the detector mesas concentrate light sufficiently to increase the effective collection area. The optical size of the mesa detectors being larger than the theoretical diffraction limit of the microlenses precludes determining whether the lenses themselves produce the theoretical diffraction-limited gain, but they clearly decrease required detector area by at least 3 - 6X. To our knowledge, this is the first successful demonstration of IR detectors and binary optics microlens integration.

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Proceedings Article | 7 October 1994

Point defects in HgCdTe by deep-level transient spectroscopy (DLTS)

Jose Colon, Jagmohan Bajaj, Jose Arias, Majid Zandian, John Pasko

Proc. SPIE. 2274, Infrared Detectors: State of the Art II

KEYWORDS: Liquid phase epitaxy, Mercury cadmium telluride, Spectroscopy, Electroluminescence, Capacitance, Diodes, Chlorine, Semiconducting wafers, Heterojunctions, Temperature metrology

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Proceedings Article | 7 October 1994

Recent progress with in-situ monitoring of mercury cadmium telluride (MCT) growth

Stuart Irvine, Jagmohan Bajaj

Proc. SPIE. 2274, Infrared Detectors: State of the Art II

KEYWORDS: Reflection, Spectroscopy, Gallium arsenide, Mercury, Reflectivity, Pyrometry, Spectroscopic ellipsometry, Reflectance spectroscopy, Semiconducting wafers, Temperature metrology

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Proceedings Article | 7 October 1994

MBE HgCdTe infrared focal plane array (IRFPA) flexible manufacturing

Jose Arias, Majid Zandian, John Pasko, Jagmohan Bajaj, Lester Kozlowski, William Tennant, Roger DeWames

Proc. SPIE. 2274, Infrared Detectors: State of the Art II

KEYWORDS: Staring arrays, Long wavelength infrared, Mercury cadmium telluride, Databases, Mercury, Manufacturing, Diodes, Heterojunctions, Arsenic, Information operations

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Proceedings Article | 15 July 1994

Study of deep levels in MBE-grown HgCdTe photodiodes by deep level transient spectroscopy

Jose Colon, Samuel Lakeou, Jagmohan Bajaj, Jose Arias, Majid Zandian, John Pasko

Proc. SPIE. 2225, Infrared Detectors and Focal Plane Arrays III

KEYWORDS: Mercury cadmium telluride, Cadmium, Spectroscopy, Mercury, Photodiodes, Diodes, Semiconducting wafers, Heterojunctions, Tellurium, Molecular beam epitaxy

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Proceedings Article | 13 July 1994

Molecular beam epitaxy (MBE) HgCdTe flexible growth technology for the manufacturing of infrared photovoltaic detectors

Jose Arias, John Pasko, Majid Zandian, Jagmohan Bajaj, Lester Kozlowski, Roger DeWames, William Tennant

Proc. SPIE. 2228, Producibility of II-VI Materials and Devices

KEYWORDS: Infrared detectors, Long wavelength infrared, Photovoltaics, Mercury cadmium telluride, Manufacturing, Infrared radiation, Infrared photography, Photovoltaic detectors, Heterojunctions, Molecular beam epitaxy

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