skip to main content


Title: Editorial: Critical Zone (CZ) Export to Streams as Indicator for CZ Structure and Function
Award ID(s):
1724171
NSF-PAR ID:
10197467
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Frontiers in Earth Science
Volume:
8
ISSN:
2296-6463
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. Richardson Zuniga SSSA 2020 
    more » « less
  2. Abstract

    High‐temperature annealing, known asTabula Rasa(TR), proves to be an effective method for dissolving oxygen precipitate nuclei inn‐Cz silicon and makes this material resistant to temperature‐induced and process‐induced lifetime degradation.Tabula Rasais especially effective inn‐Cz wafers with oxygen concentration >15 ppma. Vacancies, self‐interstitials, and their aggregates result from TR as a metastable side effect. Temperature‐dependent lifetime spectroscopy reveals that these metastable defects have shallow energy levels ~0.12 eV. Their concentrations strongly depend on the ambient gases during TR because of an offset of the thermal equilibrium between vacancies and self‐interstitials. However, these metastable defects anneal out at typical cell processing temperatures ≥850°C and have little effect on the bulk lifetime of the processed cell structures. Without dissolving built‐in oxygen precipitate nuclei, high‐temperature solar cell processing severely degrades the minority carrier lifetimes to below 0.1 millisecond, while TR‐treatedn‐Cz wafers after the cell processing steps exhibit carrier lifetimes above 2.2 milliseconds.

     
    more » « less