An improved crosspoint memory array device comprising a plurality of memory cells, each memory cell being disposed at an intersection region of bit and word conductive lines, electrically coupled to one of the first conductive lines at a first terminal and to one of the second conductive lines at a second terminal, and comprising a controllable electrical resistance, wherein a back to back Schottky diode is located between each memory cell and one of the said conductive lines, and wherein each conductive line is electrically coupled to at least two thin film transistors (TFTs). The device is substantially produced in BEOL facilities without need of front end semiconductor production facilities, yet can be made with ultra high density and low cost.