When positive ions collide with high density materials, they split and produce
many secondary particles, consequently to stop the
secondary particles more thickness material is required[9].
As the light materials weaken the protons better, using these
materials reduce the danger of secondary particles production.
According to their low density, more volume of this
material is required and against heavy materials, these materials
don’t weaken the electrons and photons well. Using
thick shields have some problems like, producing secondary
dangerous materials as neutrons and gamma ray when radiation
encounters to flake materials. Choosing useful material
as a flake can reduce it too much. Less atomic constructions
produce less secondary radiation (especially less
neutrons)[9]. Therefore, to achieve the ideal shield, multilayered
shield consist of layers with high and low density is
suitable. The optimal thickness of each light and heavy layers,
and the material, their arrangement can be optimized
depending on the radiation environment and their arrangement
also influence on dose near electronic device, sensitive
to radiation. High density shield materials (such as tungsten
and tantalum) and low density materials (such as polyethylene)
can be considered as an ideal shield[4,10]. Also, materials
such as boron 10 (B¹º), liquid hydrogen, lead enriched
plastics with oxygen are named as a shield. A parameter to
calculate the shield layer is stopping power and then reducing
its devastating effects on semiconductors, devices and
electronic equipments. The concept of stopping power is so
useful, reducing the linear energy and is defined as fol
