Selector device for bipolar RRAM is disclosed. This invention relates to high density volatile and nonvolatile memories, and more particularly to selection devices in bipolar resistive random access memory. The present day technology uses positive and negative field on memory device to change resistance states. Various metal oxides used in bipolar RRAM operations display symmetric as well as asymmetric operation. However, there is no selection device which works close to symmetric or even some asymmetric operation. A memory element is proposed for providing high density volatile/non-volatile memory storage which comprises of memory element and bipolar vertical selector device. Further, the selector device is based on punch-through mechanism concept.