In the presentation,
following two topics about radiation effects on semiconductor devices will be introduced;
[Radiation degradation of space solar cells] In space,
there are many high energy radiations such as electrons,
and heavy ions,
and space applications are affected by incidence of such radiations.
the electrical performance of solar cells degrades due to electron and proton irradiation.
This is known as “displacement damage effect”.
malfunction of electronic devices occurs even by only one heavy ion incidence,
which is called “single event effects”.
we need to know the radiation response of such devices before their launching,
in order to predict the degradation/malfunction of their electrical performance in space.
Japan Atomic Energy Agency (JAEA) studies radiation effects on space solar cells and electronic devices under the collaboration with Japanese Aerospace Exploration Agency (JAXA).
I will talk about the radiation effects on multi-junction solar cells based on III-V compounds (InGaP2/GaAs/Ge),
which are used for space applications nowadays.
The degradation modeling of the solar cell performance will be also discussed on the basis of Non Ionizing Energy Loss (NIEL) analysis.
[Transient current induced in Silicon Carbide (SiC) devices by heavy ions] We also study radiation effects on SiC devices in order to develop future devices with radiation hardness.
The transient current induced in SiC diodes by heavy ion incidence is studied using Transient Ion Beam Current (TIBIC) measurement system.
TIBIC is a very useful tool to evaluate charge induced in semiconductors by ion incidence since the transient current can be obtained by only one ion incidence.
this means that damage creation during the measurement can be minimized.
Ion species/energy dependence of the charge collection efficiency (CCE) of SiC pn diodes will be introduced in the presentation.