How to create a 3D Hemisphere? (Model of half a sphere)

Hi there!

I am a student intending to use Unity to produce a simple simulation for my Final Year Project. One component requires me to convert a sphere into a hemisphere. This is to replicate the effects of water droplets. Is there a way to do so? Or do I have to import an external model in?

Hope you can help! Much appreciated =)

Thank you!