For future space missions that are visiting hostile electron radiation environments, such as ESA’s JUICE mission, it is important to understand the effects of electron irradiation on silicon devices. This paper outlines a study to validate and improve upon the Non-Ionising Energy Loss (NIEL) model for high energy electrons in silicon using Charge Coupled Devices (CCD), CMOS Imaging Sensors (CIS) and PIPS photodiodes. Initial results of radiation effects in an e2v technologies CCD47-20 after irradiation to 10 krad of 1 MeV electrons are presented with future results and analysis to be presented in future publications.
The e2v CCD236 is a swept charge device (SCD) designed as a soft X-ray detector for spectroscopy in the range 0.8 keV
to 10 keV . It benefits from improvements in design over the previous generation of SCD (the e2v CCD54)  to
allow for increased detector area, a reduction in split X-ray events and improvements to radiation hardness . To enable
the suppression of surface dark current the device is clocked continuously, therefore there is no positional information
making responsivity variations difficult to measure. This paper describes investigated techniques to achieve a
responsivity map across the device using masking and XRF, and spot illumination from an organic light-emitting diode
(OLED). The results of this technique should allow a deeper understanding of the device sensitivity and allow better data
interpretation in SCD applications.
The Chandrayaan-2 Large Area Soft X-ray spectrometer (CLASS) is due to be launched by the Indian Space Research
Organisation (ISRO) in 2014. It will map the elemental composition of the lunar surface, building on the Chandrayaan-1
X-ray spectrometer (C1XS) heritage. CLASS will use an array of e2v technologies CCD236 swept charge devices (SCD)
providing an active detector area of approximately 64 cm2, almost three times the active area of C1XS which used the
first generation of SCD, the CCD54. The CCD236 is designed as a soft X-ray detector, 0.8 keV to 10 keV, and benefits
from improvements in design to allow for increased detector area, a reduction in split X-ray events and improvements to
radiation hardness. This paper describes the investigation into the performance requirements of the CCD236, focussing
on an optimisation of the energy resolution of a device irradiated to the estimated worse case end of life proton fluence.
The Open University, in collaboration with e2v technologies and XCAM Ltd, have been selected to fly an EO
(Earth Observation) technology demonstrator and in-orbit radiation damage characterisation instrument on
board the UK Space Agency's UKube-1 pilot Cubesat programme. Cubesat payloads offer a unique opportunity
to rapidly build and fly space hardware for minimal cost, providing easy access to the space environment. Based
around the e2v 1.3 MPixel 0.18 micron process eye-on-Si CMOS devices, the instrument consists of a radiation
characterisation imager as well as a narrow field imager (NFI) and a wide field imager (WFI). The narrow and
wide field imagers are expected to achieve resolutions of 25 m and 350 m respectively from a 650 km orbit,
providing sufficient swathe width to view the southern UK with the WFI and London with the NFI. The
radiation characterisation experiment has been designed to verify and reinforce ground based testing that has
been conducted on the e2v eye-on-Si family of devices and includes TEC temperature control circuitry as well
as RADFET in-orbit dosimetry. Of particular interest are SEU and SEL effects. The novel instrument design
allows for a wide range of capabilities within highly constrained mass, power and space budgets providing a
model for future use on similarly constrained missions, such as planetary rovers. Scheduled for launch in
December 2011, this 1 year low cost programme should not only provide valuable data and outreach
opportunities but also help to prove flight heritage for future missions.