Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > A new method to detect infrared energy using a nanoporous ZnO/n-Si photodetector

This is the photoresponse of the nanoporous ZnO/ n-Si sample under the illumination of a 1064 nm laser pulse at varying energy levels. The symbols t1 and t2 represent the corresponding time of the transient voltage peaks. The inset shows the linear relationship between the time interval, i.e. (t2-t1), and the laser pulsed energy.

Credit: ©Science China Press
This is the photoresponse of the nanoporous ZnO/ n-Si sample under the illumination of a 1064 nm laser pulse at varying energy levels. The symbols t1 and t2 represent the corresponding time of the transient voltage peaks. The inset shows the linear relationship between the time interval, i.e. (t2-t1), and the laser pulsed energy.

Credit: ©Science China Press

Abstract:
Experiments aimed at devising new types of photodetectors have been triggered by the increasing use of optoelectronic devices in personal electronics, cameras, medical equipment, computers and by the military. Professor Zhao Kun and co-researchers at the State Key Laboratory of Petroleum Resource and Prospecting, part of the China University of Petroleum in Beijing, have proposed a new type of infrared photodetector.

A new method to detect infrared energy using a nanoporous ZnO/n-Si photodetector

Beijing, China | Posted on July 1st, 2014

Photodetectors, which can convert photons to electrical signals, are used to observe and measure the wavelength or energy of light, including infrared light, which is beyond the visible spectrum. Many different types of photodetectors have been widely used in optoelectronic devices, such as digital cameras or night vision goggles. Scientists around the world are constantly exploring the potential to devise, or are actually developing, new generations of photodetectors that feature new configurations or new materials.

Zhao and colleagues state in a new study, "Double peaked decay of transient photovoltage in a nanoporous ZnO/n-Si photodetector," that this ZnO/n-Si structure has an application as a new, simple and low-cost photo-energy detector for an infrared pulsed laser. The paper was published in SCIENCE CHINA Physics, Mechanics & Astronomy.

Zinc oxide (ZnO) is a low-cost and environment-friendly semiconductor. It has a wide band gap (~3.37 eV) at room temperature, so that only ultraviolet light (with a wavelength less than 400 nm) can be absorbed effectively. In terms of photodetector applications, ZnO and ZnO-based devices are routinely studied as an ultraviolet light photosensor.

Yet researcher Zhao and his group now report that when ZnO is combined with n-type Si, an interesting photoresponse is observed under near infrared pulsed light irradiation. "In the present work, we propose a type of infrared photodetector based on a nanoporous ZnO/n-Si structure, which is synthesized by a simple sol-gel method," they state in the study. "Under illumination of one infrared laser pulse, this porous structure exhibits a double peak on a millisecond time scale in the decay of transient photovoltage."

As the structure was irradiated by a pulsed laser with a wavelength of 1064 nm, one laser pulse with energy of 0.072 mJ triggered two peaks: a higher photovoltaic (HPV) peak with an amplitude of ~235 mV and a succeeding lower photovoltaic (LPV) peak with an amplitude of ~13 mV. The time interval (t2-t1) was ~99.64 ms; t1 and t2 represent the corresponding time of the related transient photovoltaic peaks (as shown in Figure 1).

When the pulsed energy increased from 0.072 mJ to 0.332 mJ, the amplitude of the corresponding higher photovoltaic peaks increased from ~235 mV to ~275 mV. In contrast, the amplitude of the LPV peaks remained almost the same, that is, ~13 mV. The authors posited that this particular photoresponse of the nanoporous ZnO/n-Si structure originated from the synergy of the photoelectric effect and the photo-thermal excitation process.

Most importantly, the time interval between the double peaks of transient photovoltage is highly sensitive to slight changes in the energy of the laser pulse. When the irradiated pulsed energy is increased, the time interval (t2-t1) increases linearly.

This characteristic indicates that the nanoporous ZnO/n-Si structure has the potential to be developed into a new, inexpensive photodetector for an infrared pulsed laser.

###

This study received funding from the National Key Basic Research Program of China, the Specially Funded Program on National Key Scientific Instruments and Equipment Development, the Beijing National Science Foundation, and the Science Foundation of the China University of Petroleum.

####

About Science China Press
Science China Press is a leading publisher of scientific journals in China, and operates under the auspices of the Chinese Academy of Sciences. Science China Press presents to the world leading-edge advancements made by Chinese scientists across a spectrum of fields.

For more information, please click here

Contacts:
Zhao Kun

Copyright © Science China Press

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related Links

See the article:

Related News Press

News and information

UCLA chemists synthesize narrow ribbons of graphene using only light and heat: Tiny structures could be next-generation solution for smaller electronic devices December 8th, 2017

Untangling DNA: Researchers filter the entropy out of nanopore measurements December 8th, 2017

Device makes power conversion more efficient: New design could dramatically cut energy waste in electric vehicles, data centers, and the power grid December 8th, 2017

JPK Instruments announce partnership with Swiss company, Cytosurge AG. The partnership makes Cytosurge’s FluidFM® technology available on the JPK NanoWizard® AFM platform December 8th, 2017

Govt.-Legislation/Regulation/Funding/Policy

Wheat gets boost from purified nanotubes: Rice University toxicity study shows plant growth enhanced by -- but only by -- purified nanotubes December 6th, 2017

Arrowhead Presents New Clinical Data Demonstrating a Sustained Host Response in Hepatitis B Patients Following RNAi Therapy — Up to 5.0 log10 reduction in HBsAg observed; data presented at HEP DART 2017 — December 6th, 2017

Chinese market opens up for Carbodeon nanodiamonds: Carbodeon granted Chinese Patent for Nanodiamond-containing Thermoplastic Thermal Compounds December 4th, 2017

Researchers advance technique to detect ovarian cancer: Rice, MD Anderson use fluorescent carbon nanotube probes to achieve first in vivo success November 30th, 2017

Discoveries

UCLA chemists synthesize narrow ribbons of graphene using only light and heat: Tiny structures could be next-generation solution for smaller electronic devices December 8th, 2017

Untangling DNA: Researchers filter the entropy out of nanopore measurements December 8th, 2017

Device makes power conversion more efficient: New design could dramatically cut energy waste in electric vehicles, data centers, and the power grid December 8th, 2017

Wheat gets boost from purified nanotubes: Rice University toxicity study shows plant growth enhanced by -- but only by -- purified nanotubes December 6th, 2017

Announcements

UCLA chemists synthesize narrow ribbons of graphene using only light and heat: Tiny structures could be next-generation solution for smaller electronic devices December 8th, 2017

Untangling DNA: Researchers filter the entropy out of nanopore measurements December 8th, 2017

Device makes power conversion more efficient: New design could dramatically cut energy waste in electric vehicles, data centers, and the power grid December 8th, 2017

JPK Instruments announce partnership with Swiss company, Cytosurge AG. The partnership makes Cytosurge’s FluidFM® technology available on the JPK NanoWizard® AFM platform December 8th, 2017

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers

UCLA chemists synthesize narrow ribbons of graphene using only light and heat: Tiny structures could be next-generation solution for smaller electronic devices December 8th, 2017

Device makes power conversion more efficient: New design could dramatically cut energy waste in electric vehicles, data centers, and the power grid December 8th, 2017

Creating a new kind of metallic glass December 7th, 2017

Copper will replace toxic palladium and expensive platinum in the synthesis of medications: The effectiveness of copper nanoparticles as a catalyst has been proven December 5th, 2017

Military

Math gets real in strong, lightweight structures: Rice University researchers use 3-D printers to turn century-old theory into complex schwarzites November 16th, 2017

Promising sensors for submarines, mines and spacecraft: MSU scientists are developing nanostructured gas sensors that would work at room temperature November 10th, 2017

Leti Joins DARPA-Funded Project to Develop Implantable Device for Restoring Vision November 9th, 2017

Nanoshells could deliver more chemo with fewer side effects: In vitro study verifies method for remotely triggering release of cancer drugs November 8th, 2017

Photonics/Optics/Lasers

Leti Integrates Hybrid III-V Silicon Lasers on 200mm Wafers with Standard CMOS Process December 6th, 2017

Scientists make transparent materials absorb light December 1st, 2017

Going swimmingly: Biotemplates breakthrough paves way for cheaper nanobots: By using bacterial flagella as a template for silica, researchers have demonstrated an easier way to make propulsion systems for nanoscale swimming robots November 30th, 2017

Fast flowing heat in graphene heterostructures: Surprisingly fast heat flow from graphene to its surrounding November 29th, 2017

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project