JD is not a doctor degree. if anything

marginally close to fulfill your PhD dream, it would be a JSD or SJD degree, that's equivalent to PhD in Law (法理学博士）。JD is a bachelor degree in law, LLM is a master degree in law, roughly speaking. But money-wise, JD is better paid (on average) than LLM. LLM is basically for foreign students who has acquired a law degree in their own countries.