Three dimensional memory device containing dummy word lines and p-n junction at joint region and method of making the same

Abstract

A three-dimensional memory device includes a first alternating stack of first insulating layers and first electrically conductive layers located over a semiconductor material layer, an inter-tier dielectric layer, and a second alternating stack of second insulating layers and second electrically conductive layers located over the inter-tier dielectric layer. A memory opening vertically extends through the second alternating stack, the inter-tier dielectric layer, and the first alternating stack. A memory opening fill structure is located in the memory opening, and includes a first vertical semiconductor channel, a second vertical semiconductor channel, and an inter-tier doped region located between the first and the second semiconductor channel, and providing a first p-n junction with the first vertical semiconductor channel and providing a second p-n junction with the second vertical semiconductor channel.