Method to create region specific exposure in a layer
View Patent ↗A method of selectively altering material properties of a substrate in one region while making a different alteration of material properties in an adjoining region is provided. The method includes selectively masking a first portion of the substrate during a first exposure and selectively masking a second portion of the substrate during a second exposure. Additionally, a mask may be formed having more than one thickness where each thickness will selectively reduce the amount of energy from a blanket exposure of the substrate thereby allowing a substrate to receive different levels of energy dosage in a single blanket exposure.
1. A method of exposing selective regions of a substrate, comprising the steps of:
interposing a first blockout mask between a first dose of energy and a first portion of a substrate;
interposing a second blockout mask between a second dose of energy and a second portion of the substrate, the first blockout mask being a different thickness than the second blockout mask, wherein:
providing the first dose of energy comprises exposing the substrate to the first energy dose;
providing the second dose of energy comprises exposing the substrate to the second energy dose;
the first dose of energy alters a dielectric strength of the second portion of the substrate, and the second dose of energy alters a mechanical constant of the first portion of the substrate;
the first dose of energy and the second dose of energy comprise any one of at least an electron beam, an ion beam, an ultraviolet beam, an infrared beam, and an x-ray beam;
the first blockout mask comprises a first material and the second blockout mask comprises a second material, which is different from the first material and absent in the first blockout mask;
the substrate comprises an interlayer dielectric (ILD) and the ILD includes copper structures;
the second portion of the substrate is a first region of the ILD that includes the copper structures and the first portion of the substrate is a second region of the ILD that is devoid of the copper structures; and
the first blockout mask is configured to protect the second region of the ILD from energy from the first dose of energy and the second blockout mask is configured to protect the first region of the ILD from energy from the second dose of energy.
2. The method of claim 1 , wherein the first dose of energy comprises a first type of energy and the second dose of energy comprises a second type of energy.
3. The method of claim 1 , wherein the first dose of energy comprises a first amount of energy and the second dose of energy comprises a second amount of energy.
4. The method of claim 1 , wherein the interposing steps comprise forming separate blockout masks over the substrate.
5. The method of claim 1 , wherein the second region of the ILD remains substantially unaltered after the providing the first dose of energy.
6. The method of claim 5 , wherein after the providing the second dose of energy the first region of the ILD remains substantially the same as the first region was after the providing the first dose of energy.
7. A method of selectively conditioning a semiconductor layer, comprising the steps of:
exposing a first portion of the layer through a first blockout mask with a first source of energy; and
exposing a second portion of the layer through a second blockout mask with a second source of energy,
wherein:
the first blockout mask comprises a first material and the second blockout mask comprises a second material, which is different from the first material and absent in the first blockout mask;
the first source of energy alters a dielectric strength of the second portion of the layer, and the second source of energy alters a mechanical constant of the first portion of the layer;
the layer comprises an interlayer dielectric (ILD) and the ILD includes copper structures;
the second portion of the layer is a first region of the ILD that includes the copper structures and the first portion of the layer is a second region of the ILD that is devoid of the copper structures; and
the first blockout mask is configured to protect the second region of the ILD from energy from the first source of energy and the second blockout mask is configured to protect the first region of the ILD from energy from the second source of energy.
8. The method of claim 7 , further comprises forming the first blockout mask over the second portion of the layer, and exposing the first portion with the first energy source.
9. The method of claim 8 , wherein forming the first blockout mask over the second portion of the layer and forming the second blockout mask over the first portion of the layer comprises forming a single blockout mask of multiple thicknesses.
10. The method of claim 7 , wherein the first source of energy and the second source of energy comprises any one of at least an electron beam, an ion beam, an ultraviolet beam, an infrared beam, and an x-ray beam.
11. A method of selectively shielding a substrate from an energy beam, comprising the steps of:
forming a first mask over a first portion of a layer;
forming a second mask over a second portion of the layer; and
radiating the layer with a first source of energy at least once after forming the first mask; and
radiating the layer with a second source of energy,
wherein:
the first source of energy comprises a first type of energy and the second source of energy comprises a second type of energy different from the first type of energy,
the first source of energy and the second source of energy comprises any one of at least an electron beam, an ion beam, an ultraviolet beam, an infrared beam, and an x-ray beam,
the first source of energy alters a dielectric strength of the second portion of the layer, and the second source of energy alters a mechanical constant of the first portion of the layer;
the layer comprises an interlayer dielectric (ILD) and the ILD includes copper structures;
the second portion of the layer is a first region of the ILD that includes the copper structures and the first portion of the layer is a second region of the ILD that is devoid of the copper structures; and
the first mask is configured to protect the second region of the ILD from energy from the first source of energy and the second mask is configured to protect the first region of the ILD from energy from the second source of energy.
12. The method of claim 11 , wherein the forming the first mask is a blockout mask over the first portion of the layer and the forming the second mask is a blockout mask over the second portion of the layer.
13. A method of altering a material properties of a substrate, comprising the steps of:
forming a first capping layer on a substrate;
forming a second capping layer on the first capping layer;
forming a first mask over a first region of the substrate;
forming a gap in the first mask;
forming a gap in the second capping layer through the gap formed in the first mask by etching the capping layer while removing the first mask to expose a portion of the first capping layer;
forming a second mask over a portion of the second capping layer; and
exposing the substrate with an energy source in a single exposing process, resulting in subjecting the substrate to at least a first concentration of energy and a second concentration of energy dependent on material thickness of the first capping layer, the second capping layer and the second mask,
wherein the first concentration of energy alters a mechanical strength of a first portion of the substrate, and the second concentration of energy alters a dielectric constant of a second portion of the substrate.
14. The method of claim 13 , wherein the first concentration of energy comprises a first amount of energy and the second concentration of energy comprises a second amount of energy.
15. The method of claim 13 , wherein the energy source comprises any one of at least an electron beam, an ion beam, an ultraviolet beam, an infrared beam, and an x-ray beam.
16. The method of claim 13 , wherein the first mask is a first blockout mask of a first material and the second mask is a second blockout mask of a second material, which is different from the first material and absent in the first blockout mask.