Intermediate semiconductor device structures
View Patent ↗An alignment mark mask element protects an underlying alignment mark during subsequent processing of a fabrication substrate. The alignment mark mask element is formed concurrent with formation of a photomask from a dual-tone photoresist that exhibits a pattern reversal upon exposure to an energy level. A portion of the dual-tone photoresist above the alignment mark is exposed to an energy sufficient to reverse a positive tone resist to a negative tone, which remains above the alignment mark after developing. The remainder of the dual-tone photoresist is exposed through a reticle at a lesser energy level and patterned to define aperture locations of a photomask for formation of semiconductor device features. In addition, a photomask for use on a fabrication substrate and an intermediate semiconductor device are disclosed. Methods of forming a photomask and an intermediate semiconductor device structure are also disclosed.
1. An intermediate semiconductor device structure, comprising:
an exposed dual-tone photoresist material overlying a substrate having at least one alignment mark thereon, the exposed dual-tone photoresist material comprising:
a first energy-exposed portion exhibiting a first tone and having a plurality of apertures formed therethrough; and
a second energy-exposed portion abutting the first energy-exposed portion and exhibiting a second, different tone.
2. The intermediate semiconductor device structure of claim 1 , wherein the first tone is positive and the second tone is negative.
3. The intermediate semiconductor device structure of claim 1 , wherein the first energy-exposed portion exhibits a greater thickness than the second energy-exposed portion.
4. An intermediate semiconductor device structure, comprising:
a fabrication substrate comprising a plurality of semiconductor die locations thereon;
at least one alignment mark on the fabrication substrate; and
a photomask comprising:
an exposed dual-tone photoresist material comprising:
a first energy-exposed portion exhibiting a first tone and having a plurality of apertures formed therethrough; and
a second energy-exposed portion abutting the first energy-exposed portion, exhibiting a second, different tone and overlying the at least one alignment mark, the second energy-exposed portion extending to a peripheral edge of at least one of the plurality of apertures.
5. The intermediate semiconductor device structure of claim 4 , wherein the first tone is positive and the second, different tone, is negative.
6. The intermediate semiconductor device structure of claim 4 , wherein the first energy-exposed portion exhibits a greater thickness than the second energy-exposed portion.
7. A photomask for a semiconductor device structure in process, comprising:
an exposed dual-tone photoresist material comprising:
a first energy-exposed portion exhibiting a first tone and having a plurality of apertures formed therethrough; and
a second energy-exposed portion abutting the first energy-exposed portion extending to a peripheral edge of the first energy-exposed portion and exhibiting a second, different tone, wherein the second energy-exposed portion is positioned to substantially shield only an underlying alignment mark on a fabrication substrate without shielding portions of an underlying material adjacent to the underlying alignment mark.
8. The photomask of claim 7 , wherein at least one of the plurality of apertures extends to a peripheral edge of the second energy-exposed portion.
9. An intermediate semiconductor device structure, comprising:
a fabrication substrate comprising a plurality of semiconductor die locations thereon;
at least one alignment mark on the fabrication substrate; and
a photomask comprising:
an exposed dual-tone photoresist material comprising:
a first energy-exposed portion exhibiting a first tone and having a plurality of apertures formed therethrough; and
a second energy-exposed portion abutting the first energy-exposed portion and extending to a peripheral edge of at least one of the plurality of apertures, the second energy-exposed portion exhibiting a second, different tone and overlying the at least one alignment mark, wherein the second energy-exposed portion substantially shields the at least one alignment mark without shielding portions of a semiconductor device feature abutting a peripheral edge of the at least one alignment mark.
10. An intermediate semiconductor device structure, comprising:
a photoresist material overlying a substrate and comprising:
a first energy-exposed portion surrounding at least one alignment mark in the substrate and exhibiting a first tone; and
a second energy-exposed portion abutting the first energy-exposed portion and extending to a peripheral edge of the first energy-exposed portion, the second energy-exposed portion overlying the at least one alignment mark and exhibiting a second, different tone.
11. The intermediate semiconductor device structure of claim 10 , wherein a boundary of at least one of a plurality of apertures is positioned substantially at a peripheral edge of the at least one alignment mark.