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:
Nov. 16, 1999
Filed:
May. 01, 1998
Chih-Hau Hsu, Hsinchu, TW;
Utek Semiconductor Corp., , TW;
Abstract
A process for ROM coding is described. First, the active device areas and isolation regions are defined on a semiconductor substrate. Then, silicon isotopes (Si.sup.30) are implanted into the active device areas to form isotope regions. Next, the remaining portions of the MOSFET structures are then formed. Next, an interlayer dielectric layer, and a metal layer are sequentially deposited and patterned to finish the basic ROM structure. Upon the receipt of an order, a passivation layer is deposited overlaying the interlayer dielectric layer. Next, a photoresist layer is coated over the passivation layer, and code implant windows are patterned. Finally, neutron irradiation is performed to activate the silicon isotopes into N-type phosphorus ions.