Method for erasing data of a non-volatile semiconductor memory integrated circuit
AssigneeTexas Instruments Incorporated
InventorsNguyen T. Du, Akihide Asao
Life of this patent
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Abstract
A non-volatile semiconductor integrated circuit has floating poly-silicon gates on the channel regions of memory cells. The information electronically stored in said floating gates is erased by the irradiation of an X-ray with predetermined amount. The writing step prior to X-ray irradiation causes the uniform erase of entire memory cells. The circuits other than memory cells are protected by a shielding coating against the X-ray irradiation.
Claims3
A method for erasing data of a floating-gate non-volatile semiconductor memory integrated circuit comprising the steps of writing data into memory cells of said memory integrated circuit by selectively charging the floating gates thereof and erasing such data by irradiating an X-ray beam at a wavelength of 0.23 to 10 A to a dosage of approximately 10.sup.4 to 10.sup.6 Rads to said memory cells through a plastic package.
Dependencies are inferred from the claim text.