Polysilicon diodes fabricated in standard CMOS logic technologies can be used as program selectors for a programmable resistive device, such as electrical fuse, contact/via fuse, anti-fuse, or emerging nonvolatile memory such as MRAM, PCM, CBRAM, or RRAM. The diode can be constructed by P+/N+ implants on a polysilicon as a program selector. By applying a high voltage to a resistive element coupled to the P terminal of a diode and switching the N terminal of a diode to a low voltage for proper time, a current flows through a resistive element may change the resistance state. On the polysilicon diode, the spacing and doping level of a gap between the P+ and N+ implants can be controlled for different breakdown voltages and leakage currents. The Silicide Block Layer (SBL) can be used to block silicide formation on the top of polysilicon to prevent shorting. If the resistive element is a polysilicon electrical fuse, the fuse element can be merged with the polysilicon diode in one piece to save area.