Photocathode, and method for manufacturing photocathode

Patent metadata

Field	Value
Publication number	US-11728119-B2
Application number	US-202117923949-A
Country	US
Kind code	B2
Filing date	Apr 15, 2021
Priority date	May 20, 2020
Publication date	Aug 15, 2023
Grant date	Aug 15, 2023

Abstract

A photocathode 4 includes an optically transparent conductive layer provided between a translucent substrate and a photoelectric conversion layer. The optically transparent conductive layer is formed of a constituent material including carbon. A Raman spectrum of the constituent material has a peak of a band, a peak of a band, a peak of a band, and a peak of a band.

First claim

The invention claimed is:

1. A photocathode comprising:
a translucent substrate having one surface on which light is incident and an other surface emitting the light incident through the one surface;
a photoelectric conversion layer provided on the other surface of the translucent substrate and convert the light emitted through the other surface into photoelectrons; and
an optically transparent conductive layer provided between the translucent substrate and the photoelectric conversion layer,
wherein the optically transparent conductive layer is formed of a constituent material including carbon, and
wherein a Raman spectrum of the constituent material has
a peak of a D1 band,
a peak of a G band,
a peak of a 2D1 band, and
a peak of a (D1+G) band.

2. The photocathode according to claim 1 ,
wherein a smallest value of a Raman intensity between the peak of the D1 band and the peak of the G band is higher than a base value of a Raman intensity between the peak of the G band and the peak of the 2D1 band.

3. The photocathode according to claim 1 ,
wherein a Raman intensity in the peak of the D1 band is higher than a Raman intensity in the peak of the G band.

4. The photocathode according to claim 1 ,
wherein a Raman intensity in the peak of the D1 band is lower than a Raman intensity in the peak of the G band.

5. A method for manufacturing a photocathode, wherein the photocathode according to claim 1 is manufactured, the method for manufacturing a photocathode comprising:
a step of disposing a translucent substrate inside a vapor deposition device;
a step of forming an optically transparent conductive layer by introducing gas including carbon into the vapor deposition device and performing vapor deposition of a constituent material including carbon on the translucent substrate; and
a step of forming a photoelectric conversion layer on the optically transparent conductive layer.

6. The method for manufacturing a photocathode according to claim 5 ,
wherein a vapor deposition time for the constituent material is 60 minutes or shorter.

Assignees

• Univ Shizuoka Nat Univ Corp
• Hamamatsu Photonics Kk

Inventors

• Nakamura Atsushi
• Noda Yusuke

Classifications

• H01J1/34 Primary

  Photo-emissive cathodes (H01J1/35 takes precedence) · CPC title

• H01J9/12

  of photo-emissive cathodes; of secondary-emission electrodes · CPC title

• H01J43/08

  Cathode arrangements (construction of photo cathodes H01J40/06, H01J40/16, H01J47/00, H01J49/08) · CPC title

• H01J40/06 Primary

  Photo-emissive cathodes · CPC title