This paper presents new and improved approaches used in the secondary ion mass spectrometry (SIMS) for high sensitivity dopant and impurity analysis in SiC materials. With the modified hardware on our commercial SIMS instruments, we are now able achieve detection limits of 2e13 at/cm(3) for B and Al, and 1e16 at/cm(3) for N. We also made significant improvements on the detection of many other species. A new N analysis technique was developed to improve analysis precision. The results of a long-term analysis precision study on B, N, and Al will be presented, and applications of SIMS on SiC materials will also be discussed.