A method of screening weak bits in a memory array. The method includes storing a first set of data in a first memory array of the memory array, performing a first baking process on at least the first memory array or applying a first magnetic field to at least the first memory array, tracking an address of at least a first memory cell of a first set of memory cells of the first memory array, if the first memory cell of the first set of memory cells stores altered data, and at least one of replacing the first memory cell of the first set of memory cells storing the altered data with a corresponding memory cell in a second memory array of the memory array, or discarding the first memory cell of the first set of memory cells storing the altered data.