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The following parameters are given for an nMOS process: tox = 500 A° substrate doping NA = 1∙10^16 cm-3 polysilicon gate doping ND = 1∙10^20 cm-3 oxide-interface fixed-charge density N = 2∙10^10 cm-3 (a) Calculate VT for an unimplanted transistor. (b) What type and what concentration of impurities must be implanted to achieve VT = +2 V and VT = -2 V?

The following parameters are given for an nMOS process: tox = 500 A° substrate doping NA = 1∙10^16 cm-3 polysilicon gate doping ND = 1∙10^20 cm-3 oxide-interface fixed-charge density N = 2∙10^10 cm-3 (a) Calculate VT for an unimplanted transistor. (b) What type and what concentration of impurities must be implanted to achieve VT = +2 V and VT = -2 V?

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The following parameters are given for an nMOS process: tox = 500 A° substrate doping NA = 1∙10^16 cm-3 polysilicon gate doping ND = 1∙10^20 cm-3 oxide-interface fixed-charge density N = 2∙10^10 cm-3 (a) Calculate VT for an unimplanted transistor. (b) What type and what concentration of impurities must be implanted to achieve VT = +2 V and VT = -2 V?

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