Photoemission stability of negative-electron-affinity GaAs photocathodes

Tailiang Guo; Huai Rong Gao

doi:10.1117/12.142004

1 April 1993 Photoemission stability of negative-electron-affinity GaAs photocathodes

Tailiang Guo, Huai Rong Gao

Proceedings Volume 1982, Photoelectronic Detection and Imaging: Technology and Applications '93; (1993) https://doi.org/10.1117/12.142004
Event: Photoelectronic Detection and Imaging: Technology and Applications '93, 1993, Beijing, China

Abstract

Photoemission stability of the negative electron affinity (NEA) GaAs-(Cs,O) photocathode activated with several cycles of alternate Cs and O₂ adsorption at room temperature is mainly determined by the stabilization of the cesium and oxygen adlayer on the GaAs surface, and the bonding strength between this adlayer and the GaAs substrate. It is found that the light treatment (incident white light illumination) during or after the Cs and O₂ activation process can improve the emission stability of the NEA GaAs-(Cs,O) cathodes. It is also found that the emission stability of the NEA GaAs-(Cs,O) cathodes is closely related to the electronic states of cesium and oxygen before being adsorbed on the GaAs surfaces, best result being obtained with cesium ions and excited oxygen molecules. In addition to the activation procedure and experimental results, some photoinduced reactions, e.g., photoinduced adsorption, desorption, excitation, dissociation, ionization, and surface migration and surface rearrangement of the cesium and oxygen adsorbates on or from GaAs surfaces are analyzed, and their effects on the emission stability of the NEA GaAs-(Cs,O) photocathodes are discussed.

Citation Download Citation

Tailiang Guo and Huai Rong Gao "Photoemission stability of negative-electron-affinity GaAs photocathodes", Proc. SPIE 1982, Photoelectronic Detection and Imaging: Technology and Applications '93, (1 April 1993); https://doi.org/10.1117/12.142004

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available