skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.
Attention:The NSF Public Access Repository (NSF-PAR) system and access will be unavailable from 7:00 AM ET to 7:30 AM ET on Friday, April 24 due to maintenance. We apologize for the inconvenience.

Explore Research Products in the PAR
It may take a few hours for recently added research products to appear in PAR search results.


  • Home
  • Search Results
  • Page 1 of 2

Search for: All records

Creators/Authors contains: "Abbas, Ali"

Note: When clicking on a Digital Object Identifier (DOI) number, you will be taken to an external site maintained by the publisher. Some full text articles may not yet be available without a charge during the embargo (administrative interval).
What is a DOI Number?

Some links on this page may take you to non-federal websites. Their policies may differ from this site.

  1. ; ; ; ; ; ; ; (, Solar Energy Materials and Solar Cells)
    Full Text Available 
  2. ; ; (, European Journal of Operational Research)
    Full Text Available 
  3. ; ; ; ; ; ; ; ; (, Solar RRL)
    null (Ed.)
    Grading of bandgap by alloying CdTe with selenium to form a CdSexTe1–x/CdTegraded bilayer device has led to a device efficiency over 19%. A CdSexTe1–x absorber would increase the short-circuit current due to its lower bandgap but at the expense of open-circuit voltage. It has been demonstrated that adding a CdTe layer at the back of such a CdSexTe1–x film reduces the voltage deficit caused by the lower bandgap of absorber from selenium alloying while maintaining the higher short-circuit current. This leads to a photovoltaic device that draws advantage from both materials with an efficiency greater than either of them. Herein, a detailed account using device data, ultraviolet photoelectron spectroscopy, electron microscopy, and first-principles density functional theory modeling is provided, which shows that CdTe acts as an electron reflector for CdSexTe1–x 
    more » « less
    Full Text Available 
  4. ; ; ; ; ; ; ; ; ; ; et al (, Solar Energy Materials and Solar Cells)
    Full Text Available 
  5. ; ; ; ; ; ; ; ; ; (, ACS Applied Materials & Interfaces)
    Full Text Available 
  6. ; (, IEEE Systems Journal)
    null (Ed.)
    Full Text Available 
  7. ; ; ; ; ; ; ; ; ; ; et al (, Solar Energy Materials and Solar Cells)
    Full Text Available 
  8. ; ; ; (, Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films)
    Full Text Available 
  9. ; ; ; ; ; ; (, Solar Energy)
    Full Text Available 
  10. ; ; ; ; ; ; ; ; ; ; et al (, 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC))
    A thin layer of Al 2 O 3 at the back of CdSe x T e1-x /CdTe devices is shown to passivate the back interface and drastically improve surface recombination lifetimes and photoluminescent response. Despite this, such devices do not show an improvement in open-circuit voltage (V OC. ) Adding a p + amorphous silicon layer behind the Al 2 O 3 bends the conduction band upward, reducing the barrier to hole extraction and improving collection. Further optimization of the Al 2 O 3 , amorphous silicon (a-Si), and indium-doped tin oxide (ITO) layers, as well as their interaction with the CdCl 2 passivation process, are necessary to translate these electro-optical improvements into gains in voltage. 
    more » « less
    Full Text Available