Contact structure and a gate line slit and merge method to form thereof

A semiconductor device, comprising:

• a substrate;
• a stack of alternative layers including insulating layers and gate layers that are stacked alternatively over the substrate, the stack of alternative layers including an array region and a contact region;
• a plurality of channel structures disposed through the stack of alternative layers in the array region, each channel structure forming a stack of transistors in a series configuration with the gate layers being gate terminals of the stack of transistors;
• a plurality of contact structures disposed in the contact region, each contact structure electrically connecting to one of the gate layers;
• and
• a plurality of gate line trenches disposed through the stack of alternative layers in the array region and in the contact region, the gate line trenches being formed during the formation of the plurality of contact structures in the contact region.

A memory system, comprising:

• one or more memory devices and a memory controller that is coupled to and controls the one or more memory devices,
• wherein each of the one or more memory devices comprises
• a substrate,
• a stack of alternative layers including insulating layers and gate layers that are stacked alternatively over the substrate, the stack of alternative layers including an array region and a contact region,
• a plurality of channel structures disposed through the stack of alternative layers in the array region, each channel structure forming a stack of transistors in a series configuration with the gate layers being gate terminals of the stack of transistors,
• a plurality of contact structures disposed in the contact region, each contact structure electrically connecting to one of the gate layers, and
• a plurality of gate line trenches disposed through the stack of alternative layers in the array region and in the contact region, the gate line trenches being formed during the formation of the plurality of contact structures in the contact region.