Ultra-shallow dopant and ohmic contact regions by solid state diffusion
AssigneeTokyo Electron Limited
InventorRobert D. Clark
Life of this patent
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Abstract
A method of processing a substrate that includes: loading the substrate in a processing chamber, the substrate including a raised feature of a semiconductor; forming a conformal dopant layer on the raised feature by atomic layer deposition (ALD); forming a metal layer over the raised feature; thermally treating the dopant layer to form an ultra-shallow dopant region in the raised feature by diffusion of a dopant from the dopant layer into the raised feature; and thermally treating the metal layer to form an ohmic contact region in the raised feature by diffusion of a metal from the metal layer into the raised feature.
Claims18
A method of processing a substrate, the method comprising:
- loading the substrate in a processing chamber, the substrate comprising a raised feature of a semiconductor;
- forming a conformal dopant layer on the raised feature by atomic layer deposition (ALD);
- forming a metal layer over the raised feature;
- thermally treating the conformal dopant layer to form an ultra-shallow dopant region in the raised feature by diffusion of a dopant from the conformal dopant layer into the raised feature;
- and
- thermally treating the metal layer to form an ohmic contact region in the raised feature by diffusion of a metal from the metal layer into the raised feature, wherein the conformal dopant layer comprises an oxide containing the dopant, a nitride containing the dopant, or an oxynitride containing the dopant and the ohmic contact region comprises a metal silicide.
A method for forming semiconductor device, the method comprising:
- forming a dopant layer in direct contact with a silicon (Si) feature on a substrate, wherein forming the dopant layer comprises depositing an oxide, nitride, oxynitride containing a dopant;
- forming a metal layer on the dopant layer, the metal layer containing a metal to form a metal silicide in the Si feature;
- and
- performing a thermal treatment to form an ultra-shallow dopant region and a metal silicide region by diffusion of the dopant and the metal into the Si feature, the thermal treatment comprising heating the substrate to an annealing temperature,
- wherein, after forming the dopant layer and prior to the thermal treatment, the substrate is maintained below the annealing temperature.
A method of processing a substrate, the method comprising:
- loading the substrate in a processing chamber, the substrate comprising a vertical recess with a sidewall, the sidewall comprising a feature laterally protruding from a major surface of the sidewall, the feature having at least three faces exposed;
- forming a dopant layer over the feature by atomic layer deposition (ALD) at a first temperature range, the dopant layer covering at least three faces of the feature conformally, wherein forming the dopant layer comprises depositing an oxide including a dopant, a nitride including the dopant, or an oxynitride including the dopant;
- forming a metal layer over the feature at a second temperature range;
- thermally treating the dopant layer by keeping the substrate above the first temperature range and the second temperature range to form an ultra-shallow dopant region in the feature;
- and
- thermally treating the metal layer by keeping the substrate above the first temperature range and the second temperature range to form an ohmic contact region in the feature.
Dependencies are inferred from the claim text.