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 present invention provides methods, systems and system components for transferring, assembling and integrating features and arrays of features having selected nanosized and/or microsized physical dimensions, shapes and spatial orientations. Methods of the present invention utilize principles of ‘soft adhesion’ to guide the transfer, assembly and/or integration of features, such as printable semiconductor elements or other components of electronic devices. Methods of the present invention are useful for transferring features from a donor substrate to the transfer surface of an elastomeric transfer device and, optionally, from the transfer surface of an elastomeric transfer device to the receiving surface of a receiving substrate. The present methods and systems provide highly efficient, registered transfer of features and arrays of features, such as printable semiconductor element, in a concerted manner that maintains the relative spatial orientations of transferred features.

Pattern Transfer Printing by Kinetic Control of Adhesion to an Elastomeric Stamp

The present invention provides device components geometries and fabrication strategies for enhancing the electronic performance of electronic devices based on thin films of randomly oriented or partially aligned semiconducting nanotubes. In certain aspects, devices and methods of the present invention incorporate a patterned layer of randomly oriented or partially aligned carbon nanotubes, such as one or more interconnected SWNT networks, providing a semiconductor channel exhibiting improved electronic properties relative to conventional nanotubes-based electronic systems.

Medium scale carbon nanotube thin film integrated circuits on flexible plastic substrates

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

This paper describes an improved device model of GaAs MESFETs and heterojunction FETs for the design and analysis of analog integrated circuits. The proposed device model provides a new expression for the current and the capacitance of the device,which gives excellent agreements with experimental data for all regions of device operation. For the expression of the low frequency anomalies of GaAs devices, an improved technique with an equivalent circuit are presented to model the frequency dispersion of the transconductance and the drain conductance of the device, which give a good agreement with the experimental data of both the frequency dispersion and the lag effect of the device. The new device model proposed here clearly provides a superior prediction of the performance of GaAs analog integrated circuit.

An improved GaAs device model for the simulation of analog integrated circuit

The alpha-particle-induced collected charge in undoped LEC semi-insulating GaAs is measured in n/sup +/-i-n/sup +/ and n/sup +/-p-n/sup +/ isolation structures and is compared with the results of an analytical model based on a bipolar mechanism. In n/sup +/-i-n/sup +/ isolation structures, a collected-storage multiplication phenomenon induced by alpha-particle incidence is observed. The measured collected charge is about three times the alpha-particle-generated charge. This phenomenon can be attributed to charge transfer between two adjacent n/sup +/ regions. The dominant charge-collection process continues for 2.4 ns in n/sup +/-i-n/sup +/ isolation structures, but in n/sup +/-p-n/sup +/ isolation structures, it stops within 0.8 ns. The measured collected charge decreases as the isolation gap and background acceptor concentration increase. These experimental results can be explained semiquantitatively by the analytical model. This suggests that the primary mechanism of soft errors in GaAs ICs is a bipolar mechanism. >

A bipolar mechanism for alpha-particle-induced soft errors in GaAs integrated circuits

Devices to suppress low frequency noise have been developed. The devices have recess etched tracks and buried p-type layers to improve the isolation between devices. Fabricated GaAs ICs have been applied to a 2.4 Gb/s optical transmission system and have achieved a minimum optical received power of -33.2 dBm. >

Suppression of low frequency oscillations for high gain GaAs amplifiers

The primary mechanism which causes alpha-particle-induced soft error in GaAs ICs is clarified. A description is given of a charge-collection model that includes a bipolar mechanism. It is shown that mechanism causes about 90% of the total collected charge in the n-i-n isolation structure and that suppressing it is the most effective way to prevent soft error in GaAs ICs. Experimental results are presented and shown to agree with predictions based on the model. >

N. Matsunaga

Papers

An improved GaAs device model for the simulation of analog integrated circuit

A bipolar mechanism for alpha-particle-induced soft errors in GaAs integrated circuits

Suppression of low frequency oscillations for high gain GaAs amplifiers

Alpha-particle-induced soft-error mechanism in semi-insulating GaAs substrate