Semiconductor device manufacturing method
AssigneeHitachi High-Technologies Corporation
InventorsNaoyuki KOFUJI, Nobuyuki NEGISHI, Hiroaki ISHIMURA
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Abstract
In a process of dividing gates of multi-layered films in fabricating a NAND flash memory having a three-dimensional structure, a pattern is prevented from deforming and falling. A ratio of a length L to a height h of control gate groups configuring a memory cell of the flash memory is set to be less than 1.65 which is a range in which buckling does not occur. It is desirable that a ratio of a length L to a width W of the control gate groups is set to be less than 16.5.
Claims15
A semiconductor device manufacturing method comprising the step of forming a three-dimensional memory cell,
- the step of forming a three-dimensional memory cell comprising the steps of:
- stacking a plurality of control gate layers, each of which is configured as a multi-layered film of an insulating layer and a conductor layer;
- forming channel holes in the plurality of stacked control gate layers;
- and
- forming a plurality of control gate groups by forming trenches in the plurality of stacked control gate layers by etching to separate the plurality of stacked control gate layers,
- wherein a ratio obtained by dividing a maximum length in a longitudinal direction of the control gate groups by a height of the control gate groups is defined within a range in which buckling does not occur.
A semiconductor device, comprising:
- a plurality of control gate groups which comprise a plurality of control gate layers stacked and are divided from each other by trenches;
- channel holes formed in the control gate groups;
- bit lines connected to the control gate groups via electrodes;
- and
- word lines connected to the control gate layers via contact plugs,
- wherein a ratio obtained by dividing a maximum length in a longitudinal direction of the control gate groups by a height of the control gate groups is a value within a range in which buckling does not occur.
Dependencies are inferred from the claim text.