Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Photonics: Looking good

A passive alignment method offers an easy solution for fabricating integrated photonic circuits

The rise of computers in past decades was made possible largely thanks to the invention of the integrated circuit, a device that combines all necessary electronic components onto a single chip. In a similar vein, the success of optical computing is largely dependent on the possibility of integrating all essential optical components onto a single chip (photonic circuit). Lim Teck Guan at the A*STAR Institute of Microelectronics and co-workers have now developed an enhanced alignment solution for photonic circuits. “Our approach offers a highly accurate, passive optical alignment solution for these devices,” says Guan.

The fabrication of photonic circuits is no easy task because there is little room for error. In order to get the best performance from these devices operating at the visible or near-infrared spectrum, various elements must be aligned with utmost precision, typically within an error of around one micrometer. Even with the slightest misalignment, a microlens, for example, might not be able to focus light into a photodetector.

The researchers came up with an alignment method that is remarkably straightforward and easy to implement. It is based on a circular through-hole with two diameters. The design of the larger hole is not critical and it can either partially or entirely accomodate the spherical lens, depending on the application requirement. A second hole in the chip is smaller than the sphere diameter so that if the lens is pressed against the opening the sphere will automatically be aligned in its center. In this way, light from underneath the chip is guided through the lens and the second hole, and on to a photodetector that is placed directly above.

This guided assembly scheme makes it easy to fabricate more complex photonic circuits, once the spherical lenses are integrated with the layer containing the through-holes. Electronic circuits of virtually any complexity can be placed on the chip with high accuracy, so that they align perfectly with the optical beam shone through the lens. The measured efficiencies of the light coupling between the different components on the chip are promising and demonstrate light propagation with few losses.

In the current assembly, a laser is placed on a chip and through a combination of mirrors and microsphere lenses, the light is guided across the chip to a photodetector. However, the researchers have already set their sights on the advantages of further integration. “In future, we might come up with more complex circuits,” suggests Guan. “These devices could lead to applications including high-speed, high-bandwidth integrated photonic circuits, particularly if we can integrate conventional silicon electronics with photonic functionality.”


Guan, L. T. et al. Integrated optical carrier for optical/electrical interconnect. IEEE Transactions on Components, Packaging, and Manufacturing Technology 1, 125–132 (2011).

Lee Swee Heng | Research asia research news
Further information:

More articles from Power and Electrical Engineering:

nachricht Fluorescent holography: Upending the world of biological imaging
25.10.2016 | Colorado State University

nachricht Did you know that infrared heating is an essential part of automotive manufacture?
25.10.2016 | Heraeus Noblelight GmbH

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Ice shelf vibrations cause unusual waves in Antarctic atmosphere

25.10.2016 | Earth Sciences

Fluorescent holography: Upending the world of biological imaging

25.10.2016 | Power and Electrical Engineering

Etching Microstructures with Lasers

25.10.2016 | Process Engineering

More VideoLinks >>>