A method of preventing charge loss from a floating gate includes providing a substrate comprising a memory cell region and a logic region, wherein a floating gate is disposed in the memory cell region and a gate structure is disposed within the logic region, a first hard mask covers the floating gate and a second hard mask covers the first hard mask. A planarization process is performed to remove entirely the second hard mask and expose the first hard mask. Later, a third hard mask is formed to cover the first hard mask, the gate structure and the substrate, wherein the third hard mask prevents charges in the floating gate from flowing to the first hard mask. Finally, the third hard mask within the logic region is removed and the third hard mask remains within the memory region.

A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers located over a substrate, drain-select-level gate electrodes located over the alternating stack, memory openings extending through the alternating stack and a respective one of the drain-select-level gate electrodes, and memory opening fill structures located in the memory openings. The memory opening fill structures can have a stepped profile to provide a smaller lateral dimension at the level of the drain-select-level gate electrodes than within the alternating stack. Each of the drain-select-level gate electrodes includes a planar portion having two sets of vertical sidewall segments, and a set of cylindrical portions vertically protruding upward from the planar portion and laterally surrounding a respective one of the memory opening fill structures. The memory opening fill structures can be formed on-pitch as a two-dimensional array.

Electronic devices comprising a source stack comprising one or more conductive materials, a source contact adjacent to the source stack, tiers of alternating conductive materials and insulative materials adjacent to the source contact, pillars extending through the tiers and the source contact and into the source stack, a slit structure extending through the tiers and the source contact, and an implant structure extending within the slit structure and into the source stack. Related methods and systems are also disclosed.

Electronic devices comprising a source stack comprising one or more conductive materials, a source contact adjacent to the source stack, tiers of alternating conductive materials and insulative materials adjacent to the source contact, pillars extending through the tiers and the source contact and into the source stack, a slit structure extending through the tiers and the source contact, and an implant structure extending within the slit structure and into the source stack. Related methods and systems are also disclosed.

In a MONOS memory of the split-gate type formed by a field effect transistor formed on a fin, it is prevented that the rewrite lifetime of the MONOS memory is reduced due to charges being locally transferred into and out of an ONO film in the vicinity of the top of the fin by repeating the write operation and the erase operation. By forming a source region at a position spaced downward from a first upper surface of the fin in a region directly below a memory gate electrode, the current is prevented from flowing concentratedly at the upper end of the fin.

A three-dimensional NAND memory string includes an alternating stack of insulating layers and word line layers extending in a word line direction, a memory array region in the alternating stack containing memory stack structures, a group of more than two column stairs located in the alternating stack and extending in the word line direction from one side of the memory array region, and bit lines electrically contacting the vertical semiconductor channels and extending in a bit line direction which is perpendicular to the word line direction. Each column stair of the group of N column stairs has a respective step in a first vertical plane which extends in the bit line direction, and the respective steps in the first vertical plane decrease and then increase from one end column stair to another end column stair.

A three-dimensional memory device includes an alternating stacks of insulating layers and electrically conductive layers. Memory opening fill structures located in memory openings include a memory film and plural vertical semiconductor channels.

A three-dimensional memory device includes an alternating stacks of insulating layers and electrically conductive layers. Memory opening fill structures located in memory openings include a memory film and plural vertical semiconductor channels.

A memory device and a method for manufacturing the memory device are provided. The memory device includes a substrate, a plurality of first gate structures, a first dielectric layer, a second dielectric layer, a third dielectric layer and a contact plug. The first gate structures are formed on an array region of the substrate. The first dielectric layer is formed on top surfaces and sidewalls of the first gate structures. The second dielectric layer is formed on the first dielectric layer and in direct contact with the first dielectric layer. The second dielectric layer and the first dielectric layer are made of the same material. The third dielectric layer is formed between the first gate structures and defines a plurality of contact holes exposing the substrate. The contact plug fills the contact holes.

A method for manufacturing a semiconductor memory device including following steps is provided. A substrate having a first region, a second region, and a third region is provided. A first stack structure is formed on the first region. A second stack structure is formed on the second region. A third stack structure is formed on the third region. A first mask layer is formed on the substrate to cover the third stack structure. A first ion implantation process is performed, so that a second floating gate and a second control gate in the second stack structure are changed to a first conductive type. A second mask layer formed on the substrate to cover the first and second stack structures. A second ion implantation process is performed, so that a third floating gate and a third control gate in the third stack structure are changed as a second conductive type.