The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 14, 2004
Filed:
Jun. 24, 2002
Craig T. Swift, Austin, TX (US);
Jane A. Yater, Austin, TX (US);
Alexander B. Hoefler, Austin, TX (US);
Ko-Min Chang, Austin, TX (US);
Erwin J. Prinz, Austin, TX (US);
Bruce L. Morton, Austin, TX (US);
Freescale Semiconductor, Inc., Austin, TX (US);
Abstract
A non-volatile memory having a thin film dielectric storage element is programmed by hot carrier injection (HCI) and erased by tunneling. The typical structure for the memory cells for this type of memory is silicon, oxide, nitride, oxide, and silicon (SONOS). The hot carrier injection provides relatively fast programming for SONOS, while the tunneling provides for erase that avoids the difficulties with the hot hole erase (HHE) type erase that generally accompanies hot carrier injection for programming. HHE is significantly more damaging to dielectrics leading to reliability issues. HHE also has a relatively narrow area of erasure that may not perfectly match the pattern for the HCI programming leaving an incomplete erasure. The tunnel erase effectively covers the entire area so there is no concern about incomplete erase. Although tunnel erase is slower than HHE, erase time is generally less critical in a system operation than is programming time.