Integrated circuitry, memory arrays comprising strings of memory cells, methods used in forming integrated circuitry, and methods used in forming a memory array comprising strings of memory cells

Abstract

A method used in forming a memory array comprises forming a stack comprising vertically-alternating insulative tiers and conductive tiers. Channel-material strings of memory-cell strings extend through the insulative and conductive tiers. Conductive vias are formed above and individually directly electrically coupled to individual of the channel-material strings. Digitlines are formed above and are individually directly electrically coupled to a plurality of individual of the conductive vias there-below. The forming of the digitlines comprises forming lower elemental-form tungsten directly against tops of the individual conductive vias. The lower elemental-form tungsten is exposed to oxygen-containing gas or plasma to form WO, where 'x' is greater than 0 and no more than 3.0. The WOhas a maximum thickness greater than 0 and no more than 30 Angstroms in a finished construction. Upper elemental-form tungsten is physical vapor deposited directly against the WO. Other embodiments, including structure, are disclosed.