California Institute of Technology

Doheny Eye Institute

Choonsup Lee

Goutam Chattopadhyay

Imran Mehdi

Cecile D Jung-Kubiak

Robert H Lin

John J Gill

Alejandro Peralta

Ken B Cooper

Theodore J Reck

Jose Vicente Siles Perez

Jose V Siles

Harish M Manohara

Risaku Toda

Erich T Schlecht

Bertrand Thomas

Mark Salman Humayun

Yu-Chong Tai

Wolfgang Fink

Youngsam Bae

Ellis Fan-chuin Meng

Peter H Siegel

Thomas George

Emmanuel Decrossas

Sofia Rahiminejad

Eui-Hyeok Yang

Nuria Llombart Juan

Anders J Skalare

Nuria Llombart

Jacob W Kooi

Subash Khanal

Seth Sin

Sohrab Mobasser

Youngsman Bae

Sohrab Mooasser

Kungsam Bae

Yoshi Hishinuma

A waveguide based variable attenuator device including one or more attenuators each including a porous dielectric material; and a metal coating on the top of the dielectric material; and an actuator coupled to the attenuator. The actuator is configured to position, with nanometer resolution, the one or more attenuators in a waveguide configured and dimensioned to guide an electromagnetic wave having a frequency in a range of 100 gigahertz (GHz) to 1 terahertz (THz). The actuator controls at least one of a position or a volume of the one attenuator inserted in the waveguide to achieve a variable or pre-determined attenuation of the electromagnetic wave transmitted through waveguide.

Waveguide based submillimmeter-wave and terahertz variable attenuator

A solid-state device chip including diodes (generating a higher or lower frequency output through frequency multiplication or mixing of the input frequency) and a novel on-chip diplexing design that allows combination of two or more multiplier or mixer structures operating at different frequency bands within the 50-5000 GHz range within a same chip and/or waveguide. The on-chip diplexing design consists of a single-substrate multiplier chip with two or more multiplying structures each one containing 2 or more Schottky diodes. The diodes in each structure are tuned to one portion of the target frequency band, resulting in the two or more structures working together as a whole as a large broadband multiplier or mixer. Thus, an increase in bandwidth from 10-15% (current state-of-the-art) to at least 40% is achieved. Depending on the target frequencies, each subset of diodes within the chip can be designed to work either as a doubler or a tripler.

On-chip diplexed multi-band submillimeter-wave/terahertz sources

A set of antenna geometries for use in integrated arrays at terahertz frequencies are described. Two fabrication techniques to construct such antennas are presented. The first technique uses an advanced laser micro-fabrication, allowing fabricating advanced 3D geometries. The second technique uses photolithographic processes, allowing the fabrication of arrays on a single wafer in parallel.

Method for making antenna array

A silicon alignment pin is used to align successive layer of component made in semiconductor chips and/or metallic components to make easier the assembly of devices having a layered structure. The pin is made as a compressible structure which can be squeezed to reduce its outer diameter, have one end fit into a corresponding alignment pocket or cavity defined in a layer of material to be assembled into a layered structure, and then allowed to expand to produce an interference fit with the cavity. The other end can then be inserted into a corresponding cavity defined in a surface of a second layer of material that mates with the first layer. The two layers are in registry when the pin is mated to both. Multiple layers can be assembled to create a multilayer structure. Examples of such devices are presented.

Wafer-to-wafer alignment method

A solid state device chip including diodes (generating a higher frequency output through frequency multiplication of the input frequency) and a novel on-chip power combining design. Together with the on-chip power combining, the chip has increased efficiency because the diodes' anodes, being micro-fabricated simultaneously on the same patch of a GaAs wafer under identical conditions, are very well balanced. The diodes' GaAs heterostructure and the overall chip geometry are designed to be optimized for high power operation. As a result of all these features, the device can generate record-setting power having a signal frequency in the F-band and W-band (30% conversion efficiency).

High power W-band/F-band Schottky diode based frequency multipliers

A multi-pixel terahertz transceiver is constructed using a stack of semiconductor layers that communicate using vias defined within the semiconductor layers. By using a stack of semiconductor layers, the various electrical functions of each layer can be tested easily without having to assemble the entire transceiver. In addition, the design allows the production of a transceiver having pixels set 10 mm apart.

340 GHz multipixel transceiver

A silicon alignment pin is used to align successive layers of components made in semiconductor chips and/or metallic components to make easier the assembly of devices having a layered structure. The pin is made as a compressible structure which can be squeezed to reduce its outer diameter, have one end fit into a corresponding alignment pocket or cavity defined in a layer of material to be assembled into a layered structure, and then allowed to expand to produce an interference fit with the cavity. The other end can then be inserted into a corresponding cavity defined in a surface of a second layer of material that mates with the first layer. The two layers are in registry when the pin is mated to both. Multiple layers can be assembled to create a multilayer structure. Examples of such devices are presented.

Silicon alignment pins: an easy way to realize a wafer-to-wafer alignment

A multi-step silicon etching process has been developed to fabricate silicon-based terahertz (THz) waveguide components. This technique provides precise dimensional control across multiple etch depths with batch processing capabilities. Nonlinear and passive components such as mixers and multipliers waveguides, hybrids, OMTs and twists have been fabricated and integrated into a small silicon package. This fabrication technique enables a wafer-stacking architecture to provide ultra-compact multi-pixel receiver front-ends in the THz range.

Multi-step deep reactive ion etching fabrication process for silicon-based terahertz components

A novel MMIC on-chip power-combined frequency multiplier device and a method of fabricating the same, comprising two or more multiplying structures integrated on a single chip, wherein each of the integrated multiplying structures are electrically identical and each of the multiplying structures include one input antenna (E-probe) for receiving an input signal in the millimeter-wave, submillimeter-wave or terahertz frequency range inputted on the chip, a stripline based input matching network electrically connecting the input antennas to two or more Schottky diodes in a balanced configuration, two or more Schottky diodes that are used as nonlinear semiconductor devices to generate harmonics out of the input signal and produce the multiplied output signal, stripline based output matching networks for transmitting the output signal from the Schottky diodes to an output antenna, and an output antenna (E-probe) for transmitting the output signal off the chip into the output waveguide transmission line.

On-chip power-combining for high-power schottky diode based frequency multipliers

An antenna element suitable for integrated arrays at terahertz frequencies is disclosed. The antenna element comprises an extended spherical (e.g. hemispherical) semiconductor lens, e.g. silicon, antenna fed by a leaky wave waveguide feed. The extended spherical lens comprises a substantially spherical lens adjacent a substantially planar lens extension. A couple of TE/TM leaky wave modes are excited in a resonant cavity formed between a ground plane and the substantially planar lens extension by a waveguide block coupled to the ground plane. Due to these modes, the primary feed radiates inside the lens with a directive pattern that illuminates a small sector of the lens. The antenna structure is compatible with known semiconductor fabrication technology and enables production of large format imaging arrays.

Dielectric covered planar antennas

A coplanar waveguide (CPW) based subharmonic mixer working at 670 GHz using GaAs Schottky diodes. One example of the mixer has a LO input, an RF input and an IF output. Another possible mixer has a LO input, and IF input and an RF output. Each input or output is connected to a coplanar waveguide with a matching network. A pair of antiparallel diodes provides a signal at twice the LO frequency, which is then mixed with a second signal to provide signals having sum and difference frequencies. The output signal of interest is received after passing through a bandpass filter tuned to the frequency range of interest.

670 GHz Schottky diode based subharmonic mixer with CPW circuits and 70 GHz IF

Described is a device having an anti-reflection surface. The device comprises a silicon substrate with a plurality of silicon spikes formed on the substrate. A first metallic layer is formed on the silicon spikes to form the anti-reflection surface. The device further includes an aperture that extends through the substrate. A second metallic layer is formed on the substrate. The second metallic layer includes a hole that is aligned with the aperture. A spacer is attached with the silicon substrate to provide a gap between an attached sensor apparatus. Therefore, operating as a Micro-sun sensor, light entering the hole passes through the aperture to be sensed by the sensor apparatus. Additionally, light reflected by the sensor apparatus toward the first side of the silicon substrate is absorbed by the first metallic layer and silicon spikes and is thereby prevented from being reflected back toward the sensor apparatus.

Anti-reflective device having an anti-reflective surface formed of silicon spikes with nano-tips

Anti- reflective device having an anti-reflection surface formed of silicon spikes with nano-tips

An implantable intraocular pressure sensor device for detecting excessive intraocular pressure above a predetermined threshold pressure is disclosed. The device includes a pressure switch that is sized and configured to be placed in an eye, wherein said pressure switch is activated when the intraocular pressure is higher than the predetermined threshold pressure. The device is optically powered and transmits data wirelessly using optical energy. In one embodiment, the pressure sensor device is a micro electromechanical system.

Optically powered and optically data-transmitting wireless intraocular pressure sensor device

Growing community of inventors

La Palma, CA, United States of America

Choonsup Lee