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:
Oct. 16, 2018
Filed:
Aug. 21, 2017
Sandisk Technologies Llc, Plano, TX (US);
Chun Ge, San Jose, CA (US);
Fei Zhou, Milpitas, CA (US);
Yanli Zhang, San Jose, CA (US);
Raghuveer S. Makala, Campbell, CA (US);
Takashi Orimoto, Sunnyvale, CA (US);
SANDISK TECHNOLOGIES LLC, Addison, TX (US);
Abstract
At least one alternating stack of insulating layers and silicon nitride layers is formed over a substrate. Memory stack structures are formed through the at least one alternating stack. A trench and an etch mask spacer are formed such that the trench extends through the entirety of the alternating stack while the etch mask covers upper layers of the at least one alternating stack. Lower silicon nitride layers are removed employing a first hot phosphoric acid wet etch process. After removal of the etch mask spacer, upper silicon nitride layers are removed employing a second hot phosphoric acid wet etch process. Electrically conductive layers are formed in the lateral recesses formed by removal of the silicon nitride layers.