Semiconductor Device and Method of Manufacturing a Semiconductor Device Using an Alignment Layer
AssigneeInfineon Technologies Austria AG
InventorsMartin Poelzl, Oliver Blank, Franz Hirler, Maximilian Roesch, Li Juin Yip
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Abstract
First trenches extend from a process surface into a semiconductor layer. An alignment layer with mask pits in a with respect to the process surface vertical projection of the first trenches is formed on the process surface. Sidewalls of the mask pits have a smaller tilt angle with respect to the process surface than sidewalls of the first trenches. The mask pits are filled with an auxiliary material. A gate trench for a gate structure is formed in a mesa section of the semiconductor layer between the first trenches, wherein the auxiliary material is used as an etch mask.
Claims20
A method of manufacturing a semiconductor device, the method comprising:
- forming first trenches extending from a process surface into a semiconductor layer;
- forming, on the process surface, an alignment layer comprising mask pits in a with respect to the process surface vertical projection of the first trenches, wherein sidewalls of the mask pits have a smaller tilt angle with respect to the process surface than sidewalls of the first trenches;
- filling the mask pits with an auxiliary material;
- and
- forming, by using the auxiliary material as an etch mask, a gate trench for a gate structure in a mesa section of the semiconductor layer between the first trenches.
A semiconductor device comprising:
- a gate structure extending from a first surface of a semiconductor portion into a mesa section between neighboring field electrode structures;
- and
- an alignment layer formed on the first surface, wherein the alignment layer comprises mask pits in a with respect to the first surface vertical projection of portions of the field electrode structures, sidewalls of the mask pits have a smaller tilt angle with respect to the first surface than sidewalls of the field electrode structures, and the gate structure is in the vertical projection of a gap between neighboring mask pits.
Dependencies are inferred from the claim text.