AIP Publishing LLC
AIP Publishing LLC
  • pubs.aip.org
  • AIP
  • AIP China
  • University Science Books
  • Resources
    • Researchers
    • Librarians
    • Publishing Partners
    • Topical Portfolios
    • Commercial Partners
  • Publications

    Find the Right Journal

    Explore the AIP Publishing collection by title, topic, impact, citations, and more.
    Browse Journals

    Latest Content

    Read about the newest discoveries and developments in the physical sciences.
    See What's New

    Publications

    • Journals
    • Books
    • Physics Today
    • AIP Conference Proceedings
    • Scilight
    • Find the Right Journal
    • Latest Content
  • About
    • About Us
    • News and Announcements
    • Careers
    • Events
    • Leadership
    • Contact
  • pubs.aip.org
  • AIP
  • AIP China
  • University Science Books

Managing Stress Helps Transistor Performance

  • May 16, 2017
  • AIP Advances
  • News
Share:

Using tensile stress via a CESL to improve frequency performance

From the Journal: AIP Advances

WASHINGTON, D.C., May 16, 2017 — Tensile mechanical stress can have a useful effect for some transistors, where the resulting atomic strain allows its current-carrying electron-hole pairs better mobility. However, when that stress is applied to the whole device, as is a popular approach via use of what’s called contact etching stop layers (CESLs), the drift region adjacent to the stretched channel is compressed and results in reduced performance. 

A research team in China have developed a new CESL method that introduces tensile stress into both the channel and the drift region, improving overall performance by offering low drift resistance, high cut-off frequency and desirable breakdown characteristics. Their work is described in an article appearing this week in the journal AIP Advances, from AIP Publishing. 

The team of researchers became interested in the method because of work done on strained silicon techniques. During research on strained meta-oxide semiconductor field effect transistors (MOSFETs), researchers saw that the stress in the source/drain region was inverse to the channel region stress. Based on these observations, they began to study how they might use this phenomenon in a way that could enhance performance. 

This new research focused on partial silicon-on-insulator (PSOI) devices that introduce tensile stress into both the channel and the drift region using the CESLs. Simulation results also showed that the PSOI device offers better frequency performance and driving capability than unstrained devices.

“The most difficult thing for us was to find a low cost, CMOS-compatible method for applying mechanical stress,” said Xiangzhan Wang, from the University of Electronic Science and Technology of China. “During the manufacturing process, the wafer bends as the stress film (Si3N4) grows, which creates a problem in holding the wafer in process equipment.” 

The experiment results, however, increased confidence that the new strain technique could not only be applied to small devices, but also to rather large devices to yield performance improvement. With the results, even the research team was surprised at the level of improvement it provided to their simulations. 

“In our simulation, the fully tensile strained PSOI n-type LDMOSFET showed a 20-30 percent driving current improvement over normal Si LDMOSFET,” Wang said. “But when we used this strain method with a commercial Si LDMOS product, the driving current doubled yielding a current increase of more than 100 percent, which was quite surprising for us.” 

While this work has contributed to understanding of the strained Si mechanisms, there is still more to improve and understand. 

“The next research directions for the team are to optimize the fabrication process for these devices in order to obtain better stability and to try applying the same method to a nonsymmetrical device such as a tunnel FET,” Wang said.

###

For More Information:
Julia Majors
media@aip.org
301-209-3090
@AIPPhysicsNews

Article Title

Fully tensile strained partial silicon-on-insulator n-type lateral-double-diffused metal-oxide-semiconductor field effect...

Authors

Xiangzhan Wang, Changgui Tan, Xi Zou, Yi Zhang, Jianhua Pan, and Yang Liu

Author Affiliations

University of Electronic Science and Technology of China


AIP Advances

AIP Advances is a fully open access, online-only, peer-reviewed journal. It covers all areas of applied physical sciences. With its advanced web 2.0 functionality, the journal puts relevant content and discussion tools in the hands of the community to shape the direction of the physical sciences.

http://aipadvances.aip.org

Share:
  • Can the Motion of Checking Your Smartwatch Charge It?
  • Deconstructing Osmosis Provides Insight for Medical and Industrial Use

Keep Up With AIP Publishing

Sign up for the AIP newsletter to receive the latest news and information from AIP Publishing.
Sign Up

AIP PUBLISHING

1305 Walt Whitman Road,
Suite 110
Melville, NY 11747
(516) 576-2200

Resources

  • Researchers
  • Librarians
  • Publishing Partners
  • Commercial Partners

About

  • About Us
  • Careers 
  • Leadership

Support

  • Contact Us
  • Terms Of Use
  • Privacy Policy

© 2025 AIP Publishing LLC
  • 𝕏