The present invention discloses a semiconductor memory device comprising a source, a drain, a floating gate, a control gate, a recess channel and a gated p-n diode. The said p-n diode connects said floating gate and said drain. The said floating gate is for charge storage purpose, it can be electrically charged or discharged by current flowing through the gated p-n diode. An array of memory cells formed by the disclosed semiconductor memory device is proposed. Furthermore, an operating method and a method for producing the disclosed semiconductor memory device and array are described.