Three-dimensional memory device containing word lines formed by selective tungsten growth on nucleation controlling surfaces and methods of manufacturing the same

US10529620B2 · kind B2 · utility

Assignee

• Sandisk Technologies, Inc. · US

Inventors

• Rahul Sharangpani · Fremont, US
• Raghuveer S. Makala · Campbell, US
• Fei Zhou · Shanghai, CN
• Adarsh Rajashekhar · Santa Clara, US
• Senaka Kanakamedala · San Jose, US
• Fumitaka Amano · Yokkaichi, JP
• Genta Mizuno · Yokkaichi, JP

Key dates

• Filing date: Dec 4, 2017
• Grant date: Jan 7, 2020
• Expiry date: Dec 4, 2037

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D64/037
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

A method of forming a memory device includes forming an alternating stack of insulating layers and sacrificial material layers over a substrate forming memory stack structures through the alternating stack, forming a first backside trench and a second backside trench through the alternating stack, forming backside recesses by removing the sacrificial material layers, depositing a backside blocking dielectric layer after formation of the backside recesses, forming a liner that a lesser lateral extent than a lateral distance between the first backside trench and the second backside trench; and selectively growing a metal from surfaces of the liners while either not growing or growing at a lower rate the metal from surfaces of the backside recesses that are not covered by the liners.