Method and apparatus for evaluating electrostatic discharge conditions

Claim 1

A method of evaluating an environment or region for build-up of electrostatic charge sufficient to cause occurrence of electrostatic discharges that produce a failure of MOSFET gate dielectric, the method comprising the steps of: (a) encapsulating a MOSFET in a container having conductive first and second external electrodes, a gate electrode and a source or drain electrode of the MOSFET being electrically coupled to the first and second external electrodes, respectively, one of the first and second external electrodes functioning as an antenna for receiving built-up electrostatic charge, the other of the first and second external electrodes functioning as a relative ground; (b) subjecting the encapsulated MOSFET to an environment to be evaluated for electrostatic discharge occurrences, wherein electrostatic discharge occurring in the environment produces an electrostatic discharge current flowing through the antenna that produces a gate dielectric failure in the MOSFET; (c) removing the encapsulated MOSFET from the environment; (d) testing the encapsulated MOSFET by measuring an electrical parameter between the gate electrode and the source or drain electrode of the MOSFET; and (e) determining the presence or absence of a build-up of electrostatic charge in the environment or region sufficient to cause occurrence of electrostatic discharge that produces failure of the MOSFET gate dielectric by determining that the electrical parameter lies within a preselected range of values.

Claim 2

A method of evaluating an environment or region for build-up of electrostatic charge sufficient to cause occurrence of electrostatic discharges that produce a failure of MOSFET gate dielectric, the method comprising the steps of: (a) encapsulating a MOSFET in a container having conductive first and second external electrodes, a gate electrode and a source or drain electrode of the MOSFET being electrically coupled to the first and second external electrodes, respectively, one of the first and second external electrodes functioning as an antenna for receiving built-up electrostatic charge, the other of the first and second external electrodes functioning as a relative ground; (b) subjecting the encapsulated MOSFET to an environment to be evaluated for electrostatic discharge occurrences, wherein electrostatic discharge occurring in the environment produces an electrostatic discharge current flowing through the antenna that produces a gate dielectric failure in the MOSFET; (c) removing the encapsulated MOSFET from the environment; (d) testing the encapsulated MOSFET by measuring an electrical parameter between the gate electrode and the source or drain electrode of the MOSFET; and (e) determining the presence or absence of a build-up of electrostatic charge in the environment or region sufficient to cause occurrence of electrostatic discharge that produces failure of the MOSFET gate dielectric by determining that the electrical parameter lies within a preselected range of values.