In this paper, we review the progress in BiSrCaCuO-2212 Intrinsic Josephson junctions (IJJs) by summarizing our recent results in fabrication and high frequency experiments. Using a double-side fabrication process, a well defined number of intrinsic Josephson junctions in a well defined geometry can be fabricated. The junctions in the stack are quite homogeneous, and the power distribution of external irradiation among the junctions is even. Shapiro steps are clearly observed up to 2.5 THz, and the general condition for the occurrence of Shapiro steps at frequency frf is that it should be much greater than the plasma frequency fpl. Under certain conditions the Shapiro steps are zero-crossing, making some applications possible, such as quantum voltage standard etc.