Abstract:
Methods for fabricating integrated circuits are provided in various exemplary embodiments. In one embodiment, a method for fabricating an integrated circuit includes providing a germanium-based semiconductor substrate comprising a GeOx layer formed thereon having a first thickness, removing a portion of the GeOx layer by exposing the semiconductor substrate to a hydrogen-plasma dry etch so as to reduce the first thickness of the GeOx layer to a second thickness, and depositing a high-k material over the GeOx layer of the semiconductor substrate.
Abstract:
Methods for fabricating integrated circuits are provided in various exemplary embodiments. In one embodiment, a method for fabricating an integrated circuit includes providing a germanium-based semiconductor substrate comprising a GeOx layer formed thereon and exposing the semiconductor substrate to first and second atomic layer deposition (ALD) processes. The first ALD process includes exposing the semiconductor substrate to a first gaseous precursor comprising aluminum and exposing the semiconductor substrate to a second gaseous precursor comprising a first oxygen-containing precursor. The second ALD process includes exposing the semiconductor substrate to a first gaseous precursor comprising aluminum and exposing the semiconductor substrate to a second gaseous precursor comprising a second oxygen-containing precursor.
Abstract:
Metal-insulator-semiconductor (MIS) contacts for germanium and its alloys include insulator layers of oxygen-deficient metal oxide deposited by atomic layer deposition (ALD). The oxygen deficiency reduces the tunnel barrier resistance of the insulator layer while maintaining the layer's ability to prevent Fermi-level pinning at the metal/semiconductor interface. The oxygen deficiency is controlled by optimizing one or more ALD parameters such as shortened oxidant pulses, use of less-reactive oxidants such as water, heating the substrate during deposition, TMA “cleaning” of native oxide before deposition, and annealing after deposition. Secondary factors include reduced process-chamber pressure, cooled oxidant, and shortened pulses of the metal precursor.
Abstract:
Methods for fabricating integrated circuits are provided in various exemplary embodiments. In one embodiment, a method for fabricating an integrated circuit includes providing a germanium-based semiconductor substrate including a GeOx layer formed thereon having a first thickness, removing a portion of the GeOx layer by exposing the semiconductor substrate to a NF3/NH3 plasma dry etch so as to reduce the first thickness of the GeOx layer to a second thickness, and depositing a high-k material over the GeOx layer of the semiconductor substrate.