I think all PhD will have some financial assistantship and that is why it is quite competitive. I do not know whether you can transfer credit at all or the school here ackhowledge the master degree earned in China after you complete your master in China. If yes, then you can finish your master and come to the US for the PhD part (3 years?). If not, and you want to come here for PhD anyway, you might consider giving up your master. Talk to some of the programs you are interested in and find it out.