THREE-DIMENSIONAL MEMORY DEVICE INCLUDING INCLINED WORD LINE CONTACT STRIPS AND METHODS OF FORMING THE SAME

A memory device includes an alternating stack including insulating layers and electrically conductive layers and a tapered sidewall that laterally extends along a first horizontal direction and an inclined along a second horizontal direction, memory opening fill structures extending through each layer within the alternating stack and including memory elements and a vertical semiconductor channel, a cavity in the alternating stack bounded laterally by the tapered sidewall, and having a bottom surface including stepped surfaces of at least some of the electrically conductive layers, an insulating liner located over the tapered sidewall in the cavity, and electrically conductive strips which are adjoined to a respective one of the stepped surfaces at the bottom surface of the cavity, which extend over the insulating liner and the tapered sidewall in the cavity, and which include a respective topmost portion that is located above the topmost surface of the alternating stack.