Abstract: A method for evaluating gate dielectrics (100) includes providing a test structure (101). The test structure includes a gate stack that includes a gate electrode on a gate dielectric on a substrate, and at least one diffusion region diffused in the substrate including a portion below the gate stack and a portion beyond the gate stack. Pre-stress off-state I-V testing (102) is performed on the test structure to obtain pre-stress I-V test data, wherein the pre-stress off-state I-V testing includes a first measurement involving the gate electrode, the substrate and the diffusion region, a second measurement involving the gate electrode and the substrate with the diffusion region floating, and a third measurement involving the gate electrode and the diffusion region with the substrate floating. The test structure is then stressed (103) including electrically stressing for a time (t).

Abstract: A method for evaluating gate dielectrics (100) includes providing a test structure (101). The test structure includes a gate stack that includes a gate electrode on a gate dielectric on a substrate, and at least one diffusion region diffused in the substrate including a portion below the gate stack and a portion beyond the gate stack. Pre-stress off-state I-V testing (102) is performed on the test structure to obtain pre-stress I-V test data, wherein the pre-stress off-state I-V testing includes a first measurement involving the gate electrode, the substrate and the diffusion region, a second measurement involving the gate electrode and the substrate with the diffusion region floating, and a third measurement involving the gate electrode and the diffusion region with the substrate floating. The test structure is then stressed (103) including electrically stressing for a time (t).

Abstract: A composite dielectric layer (102). A first layer (112) of the composite dielectric layer (102) has a small to no nitrogen concentration. A second layer (114) of the composite dielectric layer (102) has a larger nitrogen concentration (e.g., 5-15%). The composite dielectric layer (102) may be used as a thin gate dielectric wherein the second layer (114) is located adjacent a doped gate electrode (110) and has sufficient nitrogen concentration to stop penetration of dopant from the gate electrode (110) to the channel region (108). The first layer (112) is located between the second layer (114) and the channel region (108). The low nitrogen concentration of the first layer (112) is limited so as to not interfere with carrier mobility in the channel region (108).