The present invention provides stretchable, and optionally printable, semiconductors and electronic circuits capable of providing good performance when stretched, compressed, flexed or otherwise deformed. Stretchable semiconductors and electronic circuits of the present invention preferred for some applications are flexible, in addition to being stretchable, and thus are capable of significant elongation, flexing, bending or other deformation along one or more axes. Further, stretchable semiconductors and electronic circuits of the present invention may be adapted to a wide range of device configurations to provide fully flexible electronic and optoelectronic devices.

http://science.sciencemag.org/content/sci/311/5758/208.full.pdf

Stretchable form of single crystal silicon for high performance electronics on rubber substrates

The human eye is a remarkable imaging device, with many attractive design features. Prominent among these is a hemispherical detector geometry, similar to that found in many other biological systems, that enables a wide field of view and low aberrations with simple, few-component imaging optics. This type of configuration is extremely difficult to achieve using established optoelectronics technologies, owing to the intrinsically planar nature of the patterning, deposition, etching, materials growth and doping methods that exist for fabricating such systems. Here we report strategies that avoid these limitations, and implement them to yield high-performance, hemispherical electronic eye cameras based on single-crystalline silicon. The approach uses wafer-scale optoelectronics formed in unusual, two-dimensionally compressible configurations and elastomeric transfer elements capable of transforming the planar layouts in which the systems are initially fabricated into hemispherical geometries for their final implementation. In a general sense, these methods, taken together with our theoretical analyses of their associated mechanics, provide practical routes for integrating well-developed planar device technologies onto the surfaces of complex curvilinear objects, suitable for diverse applications that cannot be addressed by conventional means.

A hemispherical electronic eye camera based on compressible silicon optoelectronics

The invention provides methods and devices for fabricating printable semiconductor elements and assembling printable semiconductor elements onto substrate surfaces. Methods, devices and device components of the present invention are capable of generating a wide range of flexible electronic and optoelectronic devices and arrays of devices on substrates comprising polymeric materials. The present invention also provides stretchable semiconductor structures and stretchable electronic devices capable of good performance in stretched configurations.

Methods and devices for fabricating and assembling printable semiconductor elements

Provided are optical devices and systems fabricated, at least in part, via printing-based assembly and integration of device components. In specific embodiments the present invention provides light emitting systems, light collecting systems, light sensing systems and photovoltaic systems comprising printable semiconductor elements, including large area, high performance macroelectronic devices. Optical systems of the present invention comprise semiconductor elements assembled, organized and/or integrated with other device components via printing techniques that exhibit performance characteristics and functionality comparable to single crystalline semiconductor based devices fabricated using conventional high temperature processing methods. Optical systems of the present invention have device geometries and configurations, such as form factors, component densities, and component positions, accessed by printing that provide a range of useful device functionalities. Optical systems of the present invention include devices and device arrays exhibiting a range of useful physical and mechanical properties including flexibility, shapeability, conformability and stretchablity.

Optical systems fabricated by printing-based assembly

Described herein are printable structures and methods for making, assembling and arranging electronic devices. A number of the methods described herein are useful for assembling electronic devices where one or more device components are embedded in a polymer which is patterned during the embedding process with trenches for electrical interconnects between device components. Some methods described herein are useful for assembling electronic devices by printing methods, such as by dry transfer contact printing methods. Also described herein are GaN light emitting diodes and methods for making and arranging GaN light emitting diodes, for example for display or lighting systems.

Printed assemblies of ultrathin, microscale inorganic light emitting diodes for deformable and semitransparent displays

Ground-based surveillance of deep space has traditionally been the purview of optical telescope systems. Unlike their imaging counterparts, space surveillance telescopes emphasize wide field of view (FOV) over resolution, permitted the most rapid survey of the entire sky. At the same time there is a constant push to detect ever fainter objects, such as small pieces of space debris or small, distant asteroids. Unfortunately increased sensitivity requires very large aperture diameters, which when combined with the requirement for wide FOV results in very fast f/# telescopes. How far this set of requirements can be expanded is typically limited by large, complex, and costly corrector optics to flatten the wavefront. An alternative approach is to design the telescope to a curved focal plane. This is an approach that was once taken with film, but it has not been feasible with electronic focal plane arrays (FPA). A major break-through in FPA design may open up a new range of telescope design options. A new array fabrication technique now provides the ability to produce FPAs with a specified degree of curvature while preserving required electro-optical characteristics. This paper presents a design for a new space surveillance telescope utilizing these curved FPAs.

Curved focal plane wide-field-of-view telescope design

Acquisition of full-polarimetric millimeter-wave, or microwave, moving target signature sets sufficient for developing ATR algorithms have proven to be costly and difficult to achieve operationally. Thorough investigations involving moving targets are often hindered by the lack of rigorously consistent signature data for a sufficient number of targets across requisite viewing angles, articulations and environmental conditions. Under the support of DARPA's TRUMPETS (through Mission Research Corporation) and AMSTE programs in conjunction with the US Army National Ground Intelligence Center (NGIC), X-band far-field turntable signature data has been acquired on 1/16th scaled models of the Bradley and BTR-70 vehicles specifically constructed for moving target investigations using ERADS' 160 GHz fully polarimetric compact range. The tracks/wheels of the scale models were translated incrementally as the radar's transmit frequency was stepped across a 10.5 GHz bandwidth. By acquiring a full frequency sweep at each track/wheel position with appropriate translation resolution, HRR RCS profiles of doppler-shifted body/track components were generated. HRR profiles of the equivalent stationary vehicle were also generated for analysis using the vehicle's HRR profiles for any given track position. These full-polarimetric HRR RCS profiles were acquired at an azimuth resolution and sweep-to-sweep phase stability sufficient for generating doppler shifted and standard ISAR imagery of either/both the moving and stationary vehicle. As a low-cost technology, this signature survey enabled researchers on the TRUMPETS and AMSTE programs to perform correlation studies between moving and stationary target HRR RCS profiles as well as ISAR imagery for a complete spin of the vehicle at a single elevation angle. [1-4] Data sampling was of sufficient density to enable researchers to simulate complex (non-linear) vehicle movement such as driving around a curve. Certainly more complex scenarios could be investigated with the existing signature data like acceleration/deceleration effects. A summary of the moving target signature data acquired is presented, along with a description and examples of the signature analysis techniques exploited. This signature data is available from NGIC on request for Government Agencies and Government Contractors with an established need-to-know.

Acquisition and analysis of X-band moving target signature data using a 160-GHz compact range

As the director of the Strategic Technology Office at the Defense Advanced Research Projects Agency (or DARPA), Timothy leads the office in development of breakthrough technologies to enable war fighters to field, operate, and adapt distributed, joint, multi-domain combat capabilities at continuous speed. He is also founder and president of Fortitude Mission Research LLC and spent several years as a senior intelligence officer with the CIA. Here he illustrates the concept of Mosaic Warfare, in which individual warfighting platforms, just like ceramic tiles in a mosaic, are placed together to make a larger picture. This philosophy can be applied to tackle a variety of human challenges including natural disasters, disruption of supply chains, climate change, pandemics, etc. He also discusses why super AI won’t represent an existential threat in the foreseeable future, but rather an opportunity for an effective division of labour between humans and machines (or human-machine symbiosis). See video at https://youtu.be/_5MkXD_m6Qc

/pdf/mosaic-warfare-and-human-machine-symbiosis-g12k1jp66d.pdf

Mosaic Warfare and Human–Machine Symbiosis

Today's radar exploitation system utilize information from both Ground Moving Target Indication (GMTI) and Synthetic Aperture Radar (SAR) obtained from various airborne platforms. GMTI detects and supports the classification of moving targets, whereas SAR detects and supports the classification of stationary targets. However, there is currently no ability to integrate the information from these two classes of radars in tracking targets that execute sequences of move-stop-move maneuvers. The solutions of this dilemma is the development of a Continuous Tracking (CT) architecture that uses distinctive GMTI and SAR features to associate stationary and moving target detections through move-stop-move maneuvers. This paper develops a theoretical model and present corresponding numeric computations of the performance of the CT syste. This theory utilizes a two- state Markov process to model the successive SAR and MTI detections are derived from typical traffic and sensor behaviors. This analysis of the sensor characteristics and the underlying traffic model provides a foundation in designing a CT systems with the maximum possible performance.

Timothy P. Grayson

Papers

Curved focal plane wide-field-of-view telescope design

Acquisition and analysis of X-band moving target signature data using a 160-GHz compact range

Mosaic Warfare and Human–Machine Symbiosis

Theoretical analysis of a continuous tracking system