A nonvolatile memory structure with pairs of serially connected select transistors connected to the top and optionally to the bottom of NAND series strings of groups of the dual-sided charge-trapping nonvolatile memory cells for controlling connection of the NAND series string to an associated bit line. A first of the serially connected select transistors has an implant to make a threshold voltage of the implanted first serially connected select transistor different from a non-implanted second serially connected select transistor. The pair of serially connected top select transistors is connected to a first of two associated bit lines. Optionally, the NAND nonvolatile memory strings further is connected a pair of serially connected bottom select transistors that is connected to the second associated bit line.