Silicon nitride

About: Silicon nitride is a research topic. Over the lifetime, 32678 publications have been published within this topic receiving 413599 citations. The topic is also known as: N₄Si₃.

Uniform batch film deposition process and films so produced

Abstract: A batch of wafer substrates is provided with each wafer substrate having a surface. Each surface is coated with a layer of material applied simultaneously to the surface of each of the batch of wafer substrates. The layer of material is applied to a thickness that varies less than four thickness percent across the surface and exclusive of an edge boundary and having a wafer-to-wafer thickness variation of less than three percent. The layer of material so applied is a silicon oxide, silicon nitride or silicon oxynitride with the layer of material being devoid of carbon and chlorine. Formation of silicon oxide or a silicon oxynitride requires the inclusion of a co-reactant. Silicon nitride is also formed with the inclusion of a nitrification co-reactant. A process for forming such a batch of wafer substrates involves feeding the precursor into a reactor containing a batch of wafer substrates and reacting the precursor at a wafer substrate temperature, total pressure, and precursor flow rate sufficient to create such a layer of material. The delivery of a precursor and co-reactant as needed through vertical tube injectors having multiple orifices with at least one orifice in registry with each of the batch of wafer substrates and exit slits within the reactor to create flow across the surface of each of the wafer substrates in the batch provides the within- wafer and wafer-to-wafer uniformity.

The mechanical properties of atomic layer deposited alumina for use in micro- and nano-electromechanical systems

Abstract: Mechanical characterization of atomic layer deposited (ALD) alumina (Al2O3) for use in micro- and nano-electromechanical systems has been performed using several measurement techniques including: instrumented nanoindentation, bulge testing, pointer rotation, and nanobeam deflection Using these measurement techniques, we determine Young's modulus, Berkovitch hardness, universal hardness and the intrinsic in-plane stress for ALD Al2O3 Specifically, measurements for ALD Al2O3 films deposited at 177 degrees C with thicknesses between 50 and 300 nm are reported The measured Young's modulus is in the range of 168-182 GPa, Berkovitch hardness is 123 GPa, universal hardness is 8 GPa, and the intrinsic in-plane stress is in the range of 383-474 MPa Multiple measurements of the same material property from different measurement techniques are presented and compared ALD Al2O3 is an advantageous material to use over various forms of silicon nitride, for micro- and nano-electromechanical systems due in part to the low deposition temperature that allows for integration with CMOS processing Also, Al2O3, unlike silicon nitride, has a high chemical resistance to dry-chemistry Si etchants Although ALD Al2O3 has recently been used as both a coating and a structural layer for micro- and nano-electromechanical systems, its mechanical properties were not previously described

Silicon nitride CMOS-compatible platform for integrated photonics applications at visible wavelengths

Abstract: Silicon nitride is demonstrated as a high performance and cost-effective solution for dense integrated photonic circuits in the visible spectrum. Experimental results for nanophotonic waveguides fabricated in a standard CMOS pilot line with losses below 0.71dB/cm in an aqueous environment and 0.51dB/cm with silicon dioxide cladding are reported. Design and characterization of waveguide bends, grating couplers and multimode interference couplers (MMI) at a wavelength of 660 nm are presented. The index contrast of this technology enables high integration densities with insertion losses below 0.05 dB per 90° bend for radii as small as 35 µm. By a proper design of the buried oxide layer thickness, grating couplers with efficiencies above 38% for the TE polarization have been obtained.

Low hydrogen content stoichiometric silicon nitride films deposited by plasma‐enhanced chemical vapor deposition

Abstract: We have deposited silicon nitride films by plasma‐enhanced chemical vapor deposition (PECVD) at 250 °C with properties similar to films prepared at 700 °C by low‐pressure chemical vapor deposition (LPCVD). Films are prepared using silane and nitrogen source gases with helium dilution. The film properties, including N/Si ratio, hydrogen content and electrical quality are most sensitive to changes in the silane flow rate during deposition. For films deposited under optimized conditions at a substrate temperature of 250 °C, current versus voltage measurements in metal‐insulator‐semiconductor structures show the onset of carrier injection at 3–4 MV/cm, slightly lower than LPCVD films. When bias‐stressed to 2 MV/cm, capacitance versus voltage measurements show some hysteretic behavior and evidence for positive fixed charge, similar to LPCVD films. For the optimized films: N/Si=1.33±.02; refractive index (λ=6328 A)=1.980±0.01; dielectric constant (1 MHz) ∼7.5; density=2.7±0.1; and the etch rate in 10% buffered ...

Method to increase tensile stress of silicon nitride films using a post PECVD deposition UV cure

Abstract: High tensile stress in a deposited layer such as silicon nitride, may be achieved utilizing one or more techniques, employed alone or in combination. High tensile stress may be achieved by forming a silicon-containing layer on a surface by exposing the surface to a silicon-containing precursor gas in the absence of a plasma, forming silicon nitride by exposing said silicon-containing layer to a nitrogen-containing plasma, and then repeating these steps to increase a thickness of the silicon nitride created thereby. High tensile stress may also be achieved by exposing a surface to a silicon-containing precursor gas in a first nitrogen-containing plasma, treating the material with a second nitrogen-containing plasma, and then repeating these steps to increase a thickness of the silicon nitride formed thereby. In another embodiment, tensile film stress is enhanced by deposition with porogens that are liberated upon subsequent exposure to UV radiation or plasma treatment.