Perhaps that's true. But I just don't remember any scientist saying "here's the evidence of evolution, and it proves that God doesn't exist".
I think you're projecting "atheism" onto evolution. Any honest scientist cannot make any claim about the existence of God, one way or the other. Evolution, or no.
Many people see atheism and evolution as having a connection. I don't know about other scientific disciplines but it certainly seems so with regard to evolution. Probably the whole Genesis thing. I don't know anyone who questions the laws of physics or astronomy or geology like they do evolution. Of course, that doesn't mean they don't, just I don't see it. And again, I think the major stumbling block is the ape to man thing. Just anecdotal articles I've read lead me to believe quite a few evolutionists are atheists or at least agnostics. I did have an article with figures but like polls, they don't mean a whole lot.