Patent attributes
A memory device includes a string of series-connected memory cells, a data line, a first select transistor, a common source, a second select transistor, and a gate leakage transistor. The string of series-connected memory cells includes a vertical channel region. Each memory cell of the string of series-connected memory cells includes a first gate stack structure. The data line is connected to the vertical channel region. The first select transistor is connected between the data line and the string of series-connected memory cells. The second select transistor is connected between the common source and the string of series-connected memory cells. The gate leakage transistor is connected between the first select transistor and the second select transistor. The gate leakage transistor includes a second gate stack structure different from the first gate stack structure.