Modification of the surface band-bending of a silicon CCD for low-energy electron detection
Abstract
Silicon CCDs have limited sensitivity to particles and photons with short penetration depth, due to the surface depletion caused by the inherent positive charge in the native oxide. Because of surface depletion, internally-generated electrons are trapped near the irradiated surface and therefore cannot be transported to the detection circuitry. This deleterious surface potential can be eliminated by low-temperature molecular beam epitaxial (MBE) growth of a delta-doped layer on the Si surface. This effect has been demonstrated through achievement of 100% internal quantum efficiency for UV photons detected with delta-doped CCDs. In this paper, we will discuss the modification of the band bending near the CCD surface by low-temperature MBE and report the application of delta-doped CCDs to low-energy electron detection. We show that modification of the surface can greatly improve sensitivity to low-energy electrons. Measurements comparing the response of delta-doped CCDs with untreated CCDs were made in the 50 eV-1.5 keV energy range. For electrons with energies below 300 eV, the signal from untreated CCDs was below the detection limit for our apparatus, and data are presented only for the response of delta-doped CCDs at these energies. The effects of multiple electron hole pair (EHP) production and backscattering on the observed signals are discussed.
Additional Information
© Materials Research Society 1997. The authors gratefully acknowledge the invaluable assistance of Drs.,L. Douglas Bell, Michael Hoenk, Steve Manion, Tom Van Zandt, Mr. Walter Proniawicz, and Professor LC. Kimerling. The work presented in this paper was performed by the Center for Space Microelectronics Technology, Jet Propulsion Laboratory, California Institute of Technology, and was jointly funded by the Caltech President's fund and the NASA Office of Space Science.Attached Files
Published - 386593.pdf
Files
Name | Size | Download all |
---|---|---|
md5:d4ee11d0bb99ae62f473dbe25bdc1e08
|
294.4 kB | Preview Download |
Additional details
- Eprint ID
- 50950
- Resolver ID
- CaltechAUTHORS:20141028-133726362
- Caltech President's Fund
- NASA
- Created
-
2014-10-28Created from EPrint's datestamp field
- Updated
-
2021-11-10Created from EPrint's last_modified field
- Series Name
- Materials Research Society Conference Proceedings
- Series Volume or Issue Number
- 448