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A 6T-SRAM macro with the VTH shift variation self-convergence scheme of the asymmetric pass gate transistor by the local electron injection is proposed. The statistical VTH shift variation of the pass gate (PG) transistor is measured and the positive correlation between the PG transistor VTH shift and its original VTH due to VD effect is self-compensated by the negative correlation between those by ID effect. As a result, the measured PG transistor VTH shift is less correlated with the VTH of PG before injection. In order to enhance ID effect and reduce VD effect for a self-convergence in VTH shift, near threshold VWL self-convergence injection scheme is proposed. The proposed scheme reduces VD effect by 38% and enhances ID effect by 20%. Furthermore, the fabricated SRAM macro demonstrates 3 times larger word-line operation voltage window, 41% less read margin variation and 80mV lower VCCMIN after the local electron injection.