Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International



Home > Press > Record-breaking hole mobility heralds a flexible future for electronics: Researchers from The University of Tsukuba grow a germanium thin film on a flexible polyimide substrate, resulting in a material with the highest hole mobility reported to date

Researchers from the University of Tsukuba have produced a record-breaking polycrystalline germanium (Ge) thin film on a flexible polyimide substrate. Tuning the growth temperature and thickness of the GeOx underlayer gave a Ge film with large crystals and a hole mobility of 690 cm2 V−1 s−1, the highest reported for an insulator-supported semiconductor. The high-performance, flexible material is expected to contribute to the development of electronics for large-scale initiatives such as the internet of things.

CREDIT
University of Tsukuba
Researchers from the University of Tsukuba have produced a record-breaking polycrystalline germanium (Ge) thin film on a flexible polyimide substrate. Tuning the growth temperature and thickness of the GeOx underlayer gave a Ge film with large crystals and a hole mobility of 690 cm2 V−1 s−1, the highest reported for an insulator-supported semiconductor. The high-performance, flexible material is expected to contribute to the development of electronics for large-scale initiatives such as the internet of things. CREDIT University of Tsukuba

Abstract:
Technologists envisage an electronically interconnected future that will depend on cheap, lightweight, flexible devices. Efforts to optimize the semiconductor materials needed for these electronic devices are therefore necessary. Researchers from the University of Tsukuba have reported a record-breaking germanium (Ge) thin film on a plastic substrate that offers flexibility without compromising performance. Their findings are published in ACS Applied Electronic Materials (Supplementary Journal Cover).

Record-breaking hole mobility heralds a flexible future for electronics: Researchers from The University of Tsukuba grow a germanium thin film on a flexible polyimide substrate, resulting in a material with the highest hole mobility reported to date

Tsukuba, Japan | Posted on December 24th, 2021

Ge is a popular semiconductor for use in transistors because it has high charge carrier mobility (charge carrier refers to the electrons and electron holes that move through the material). Ge can also be processed at the relatively low temperature of ~500°C and has a low Young’s modulus, which means it is a softer alternative to commonly used materials such as silicon.

Ge thin films can be grown using the solid-phase crystallization technique. These thin films are polycrystalline, meaning they are made up of many Ge crystals. In general, larger crystals lead to greater carrier mobilities because bigger crystals form fewer grain boundaries that obstruct the current. Recent increases in grain size have therefore led to effective Ge thin-film transistors on rigid substrates such as glass.

However, many of the plastic substrates used to introduce flexibility are not resistant to temperature above 400°C, which makes it difficult to grow high quality crystals with appropriate carrier mobility.

Now, the researchers have used a polyimide film that can withstand temperatures up to 500°C. This allowed post-annealing treatment of the films, meaning crystal quality was not compromised for flexibility.

“We grew a GeOx layer directly on the flexible polyimide, then the Ge film on top of that,” explains study lead author Professor Kaoru Toko. “Oxygen that diffused into the Ge from the GeOx layer helped to achieve large crystals. We found that the Ge crystallinity was influenced by both the thickness of the GeOx layer and the temperature at which the Ge layer was grown.”

In this study, the largest Ge crystals observed were approximately 13 µm in diameter and grown at 375°C on a 100-nm-thick GeOx layer. The large grain size resulted in the film having a hole mobility of 690 cm2 V−1 s−1, which is the highest value reported to date for a semiconductor on an insulating substrate.

“Our record-breaking film is a significant step forward for transistor technology,” says Professor Toko. “Its high performance, combined with its flexibility, affordability, and portability, make it perfectly suited to the development of new flexible devices such as wearable electronics to support future digital initiatives such as the internet of things.”

####

For more information, please click here

Contacts:
Naoko Yamashina
University of Tsukuba

Copyright © University of Tsukuba

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

The study, “Record-high hole mobility germanium on flexible plastic with controlled interfacial reaction”, was published in ACS Applied Electronic Materials (Supplementary Journal Cover)at DOI: 10.1021/acsaelm.1c00997.

Related News Press

News and information

Engineering piezoelectricity and strain sensitivity in CdS to promote piezocatalytic hydrogen evolution May 13th, 2022

New nanomechanical oscillators with record-low loss May 13th, 2022

Small microring array enables large complex-valued matrix multiplication May 13th, 2022

Study finds nanomedicine targeting lymph nodes key to triple negative breast cancer treatment: In mice, nanomedicine can remodel the immune microenvironment in lymph node and tumor tissue for long-term remission and lung tumor elimination in this form of metastasized breast cance May 13th, 2022

Flexible Electronics

A molecule like a nanobattery: Chemical scientists decipher complex electronic structure of a three-nuclear metallorganic compound with the capacity of donating and receiving multiple electrons June 9th, 2021

Threads that sense how and when you move? New technology makes it possible: Engineers created thread sensors that can be attached to skin to measure movement in real time, with potential implications for tracking health and performance January 29th, 2021

Going Organic: uOttawa team realizing the limitless possibilities of wearable electronics January 28th, 2021

Engineers find antioxidants improve nanoscale visualization of polymers January 8th, 2021

Govt.-Legislation/Regulation/Funding/Policy

Lightening up the nanoscale long-wavelength optoelectronics May 13th, 2022

On-Chip Photodetection: Two-dimensional material heterojunctions hetero-integration May 13th, 2022

Small microring array enables large complex-valued matrix multiplication May 13th, 2022

The future of desalination? A fast, efficient, selective membrane for purifying saltwater May 13th, 2022

Possible Futures

Engineering piezoelectricity and strain sensitivity in CdS to promote piezocatalytic hydrogen evolution May 13th, 2022

New nanomechanical oscillators with record-low loss May 13th, 2022

Small microring array enables large complex-valued matrix multiplication May 13th, 2022

Study finds nanomedicine targeting lymph nodes key to triple negative breast cancer treatment: In mice, nanomedicine can remodel the immune microenvironment in lymph node and tumor tissue for long-term remission and lung tumor elimination in this form of metastasized breast cance May 13th, 2022

Chip Technology

Going gentle on mechanical quantum systems: New experimental work establishes how quantum properties of mechanical quantum systems can be measured without destroying the quantum state May 13th, 2022

On-Chip Photodetection: Two-dimensional material heterojunctions hetero-integration May 13th, 2022

Small microring array enables large complex-valued matrix multiplication May 13th, 2022

Rice ‘metalens’ could disrupt vacuum UV market: Solid-state nanophotonic technology could potentially replace cabinets of equipment May 6th, 2022

Discoveries

Going gentle on mechanical quantum systems: New experimental work establishes how quantum properties of mechanical quantum systems can be measured without destroying the quantum state May 13th, 2022

New nanomechanical oscillators with record-low loss May 13th, 2022

Small microring array enables large complex-valued matrix multiplication May 13th, 2022

Study finds nanomedicine targeting lymph nodes key to triple negative breast cancer treatment: In mice, nanomedicine can remodel the immune microenvironment in lymph node and tumor tissue for long-term remission and lung tumor elimination in this form of metastasized breast cance May 13th, 2022

Announcements

Engineering piezoelectricity and strain sensitivity in CdS to promote piezocatalytic hydrogen evolution May 13th, 2022

New nanomechanical oscillators with record-low loss May 13th, 2022

Small microring array enables large complex-valued matrix multiplication May 13th, 2022

Study finds nanomedicine targeting lymph nodes key to triple negative breast cancer treatment: In mice, nanomedicine can remodel the immune microenvironment in lymph node and tumor tissue for long-term remission and lung tumor elimination in this form of metastasized breast cance May 13th, 2022

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

Lightening up the nanoscale long-wavelength optoelectronics May 13th, 2022

On-Chip Photodetection: Two-dimensional material heterojunctions hetero-integration May 13th, 2022

Development of high-durability single-atomic catalyst using industrial humidifier: Identification of the operating mechanism of cobalt-based single-atomic catalyst and development of a mass production process. Utilization for catalyst development in various fields including fuel May 13th, 2022

Engineering piezoelectricity and strain sensitivity in CdS to promote piezocatalytic hydrogen evolution May 13th, 2022

Grants/Sponsored Research/Awards/Scholarships/Gifts/Contests/Honors/Records

Lightening up the nanoscale long-wavelength optoelectronics May 13th, 2022

On-Chip Photodetection: Two-dimensional material heterojunctions hetero-integration May 13th, 2022

Small microring array enables large complex-valued matrix multiplication May 13th, 2022

Study finds nanomedicine targeting lymph nodes key to triple negative breast cancer treatment: In mice, nanomedicine can remodel the immune microenvironment in lymph node and tumor tissue for long-term remission and lung tumor elimination in this form of metastasized breast cance May 13th, 2022

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




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project