A memory device, comprising: a plurality of non-volatile memory cells, wherein each of the non-volatile memory cells comprises: spaced apart source and drain regions (14, 16) formed in a semiconductor substrate, with a channel region of the substrate extending there between, a floating gate disposed vertically over and insulated from a first portion of the channel region, a select gate disposed vertically over and insulated from a second portion of the channel region, and a control gate disposed vertically over and insulated from the floating gate; and a controller configured to: erase the plurality of non-volatile memory cells, program each of the non-volatile memory cells, for each of the non-volatile memory cells measure a threshold voltage applied to a non-volatile memory cell corresponding to a target current through the memory cell in a first read operation using read operation parameters, re-measure a threshold voltage applied to the non-volatile memory cell corresponding to the target current through the non-volatile memory cell in a second read operation using the read operation parameters, and identify the non-volatile memory cell as defective if a difference between the measured threshold voltage and the re-measured threshold voltage exceeds a predetermined amount. a plurality of non-volatile memory cells, wherein each of the non-volatile memory cells comprises: spaced apart source and drain regions (14, 16) formed in a semiconductor substrate, with a channel region of the substrate extending there between, a floating gate disposed vertically over and insulated from a first portion of the channel region, a select gate disposed vertically over and insulated from a second portion of the channel region, and a control gate disposed vertically over and insulated from the floating gate; and spaced apart source and drain regions (14, 16) formed in a semiconductor substrate, with a channel region of the substrate extending there between, a floating gate disposed vertically over and insulated from a first portion of the channel region, a select gate disposed vertically over and insulated from a second portion of the channel region, and a control gate disposed vertically over and insulated from the floating gate; and a controller configured to: erase the plurality of non-volatile memory cells, program each of the non-volatile memory cells, for each of the non-volatile memory cells measure a threshold voltage applied to a non-volatile memory cell corresponding to a target current through the memory cell in a first read operation using read operation parameters, re-measure a threshold voltage applied to the non-volatile memory cell corresponding to the target current through the non-volatile memory cell in a second read operation using the read operation parameters, and identify the non-volatile memory cell as defective if a difference between the measured threshold voltage and the re-measured threshold voltage exceeds a predetermined amount. erase the plurality of non-volatile memory cells, program each of the non-volatile memory cells, for each of the non-volatile memory cells measure a threshold voltage applied to a non-volatile memory cell corresponding to a target current through the memory cell in a first read operation using read operation parameters, re-measure a threshold voltage applied to the non-volatile memory cell corresponding to the target current through the non-volatile memory cell in a second read operation using the read operation parameters, and identify the non-volatile memory cell as defective if a difference between the measured threshold voltage and the re-measured threshold voltage exceeds a predetermined amount. measure a threshold voltage applied to a non-volatile memory cell corresponding to a target current through the memory cell in a first read operation using read operation parameters, re-measure a threshold voltage applied to the non-volatile memory cell corresponding to the target current through the non-volatile memory cell in a second read operation using the read operation parameters, and identify the non-volatile memory cell as defective if a difference between the measured threshold voltage and the re-measured threshold voltage exceeds a predetermined amount.