A vertical repetition of a unit layer stack includes an insulating layer, a first sacrificial material layer, another insulating layer, and a second sacrificial material layer. A memory opening is formed through the vertical repetition, and a memory opening fill structure is formed in the memory opening. A backside trench is formed through the alternating stack. The first sacrificial material layers are replaced with first electrically conductive layers, and the second sacrificial material layer are replaced with second electrically conductive layers after formation of the first electrically conductive layers.