Maybe someone here can give a better answer, but I consider solid state physics to be the basis of materials science, which is to say that every materials science topic overlaps with SSP. A good analogy is chemistry and physics - to study chemistry, you can memorize rules and laws, but to truly understand reactions and electron exchange, you need to understand how subatomic particles behave fundamentally. Similarly, to understand how materials grow and behave, you need to understand the underlying structure of its atoms and the consequences of their arrangement.