Skip to content

STRUCTURAL CHARACTERIZATION OF THE NEW DIAMOND-LIKE SEMICONDUCTOR CuNbGaSe3

MetadataDetails
Publication Date2018-01-20
JournalPERIÓDICO TCHÊ QUÍMICA
AuthorsJesĂșs Alberto Flores Cruz, GerzĂłn E. Delgado, Jines E. Contreras, M. Quintero, Luis Nieves
InstitutionsUniversidad de Los Andes
Citations2
AnalysisFull AI Review Included

This documentation summarizes the structural characterization of the novel diamond-like semiconductor CuNbGaSe3 and outlines how 6CCVD’s advanced MPCVD diamond products facilitate research and development in related high-performance material systems.

  • Novel Material: The research focuses on CuNbGaSe3, a new quaternary chalcogenide semiconductor belonging to the I-II-III-VI3 family.
  • High Value Proposition: This material is significant because it exhibits magnetic behavior, enabling potential spintronic applications—a major improvement over simpler chalcopyrite semiconductors (like CuGaSe2).
  • Structure: The material crystallizes in a tetragonal, normal adamantane-structure, specifically the space group P42c (N° 112), representing a symmetry degradation from the standard chalcopyrite I&bar;42d structure.
  • Purity: The synthesized powder sample achieved a high phase purity of 94.2% for the principal CuNbGaSe3 compound.
  • Synthesis Method: Polycrystalline ingots were created using a high-temperature melt and anneal technique (up to 1150 °C) using 99.99 weight% pure starting materials.
  • 6CCVD Relevance: The development of high-performance spintronic devices relies heavily on robust substrates. 6CCVD provides the necessary ultra-pure Single Crystal Diamond (SCD) and Boron-Doped Diamond (BDD) required to build or integrate these diamond-like semiconductors into functional devices.

The following key physical and structural data were derived from the X-ray powder diffraction and Rietveld refinement of the CuNbGaSe3 compound.

ParameterValueUnitContext
Primary Phase Purity94.2%CuNbGaSe3 Weight Fraction
Secondary Phase Purity5.8%Cu0.667NbSe2 Weight Fraction
Crystal SystemTetragonalN/AAdamantane-type structure
Space GroupP42cN° 112Related to Chalcopyrite I&bar;42d
Lattice Parameter (a)5.6199(4)ÅUnit cell dimension
Lattice Parameter (c)11.0275(2)ÅUnit cell dimension
Unit Cell Volume (V)348.28(4)ųCalculated volume
Calculated Density (Dcalc)5.83g/cmÂłDensity of primary phase
Rietveld R-Factor (Rwp)8.9%Measure of fit quality
Cu-Se Bond Distance2.425(8)ÅCalculated from refinement
Nb-Se Bond Distance2.445(8)ÅCalculated from refinement
Synthesis Peak Temperature1150°CHeld for 24 hours (Melt Stage)
Synthesis Anneal Temperature650°CHeld for one month (Final Anneal)

The CuNbGaSe3 compound was synthesized using a melt and anneal technique, and characterized via high-resolution X-ray powder diffraction (XRPD).

  1. Material Preparation:
    • Starting materials (Cu, Nb, Ga, Se) of 99.99 weight% purity were mixed in stoichiometric ratio.
    • The mix was sealed in an evacuated quartz tube, pre-carbonized internally to prevent element reaction with the quartz.
  2. Thermal Processing - Stage 1 (Initial Anneal):
    • The ampoule was slowly heated to 450 °C.
    • Temperature was maintained for 48 hours.
  3. Thermal Processing - Stage 2 (Melt):
    • Temperature was raised slowly to 1150 °C.
    • Temperature was maintained for 24 hours, with continuous mechanical shaking to ensure homogeneity.
  4. Thermal Processing - Stage 3 (Cooling/Final Anneal):
    • Cooled to room temperature at a very low rate over one week.
    • The ampoule was placed in a furnace at 650 °C and held for a further one month (final anneal).
  5. Characterization (XRPD):
    • Sample powder was mounted on a flat zero-background holder.
    • Data collected at 293(1) K using a Siemens D5005 diffractometer.
    • Used CuKα radiation (λ = 1.54056 Å).
    • Instrument operated at 40kV and 30mA.
    • Scan range: 10° to 100° 2θ, with a step size of 0.02° and counting time of 40s.
  6. Structural Refinement:
    • Rietveld method was employed to refine the crystal structure and derive atomic coordinates and bond distances.

The research highlights the potential of complex diamond-like semiconductors for advanced spintronic and photonic applications. 6CCVD provides the specialized MPCVD diamond platforms essential for fabricating, integrating, and scaling these next-generation devices.

Research Requirement/Application6CCVD Solution & Capability
Platform for Spintronic MaterialsOptical Grade Single Crystal Diamond (SCD): Required for applications involving magnetic fields, spin coherence, or integration with diamond’s native Nitrogen-Vacancy (NV) centers. Our SCD offers superior thermal management and structural purity, ideal for heteroepitaxial growth of quaternary semiconductors like CuNbGaSe3.
Conductive Diamond InterfacesHeavy Boron-Doped Diamond (BDD): We supply highly conductive BDD films, which are critical for creating active electrodes, integrating ohmic contacts, and developing all-diamond or hybrid diamond-semiconductor devices essential for spintronics.
Material Dimensions & ScalingCustom Dimensions up to 125mm: While the study used small ingots, 6CCVD produces PCD wafers up to 125mm and large-format SCD substrates, enabling the transition from laboratory synthesis to commercial-scale device fabrication.
Surface Quality for EpitaxyAtomic-Scale Polishing: Achieving precise structural degradation (like P42c from I&bar;42d) requires pristine substrate surfaces. We guarantee Ra < 1nm for SCD and Ra < 5nm for inch-size PCD to ensure optimal lattice matching and high-quality film deposition.
Custom Device IntegrationIn-House Metalization & Patterning: Successful device creation requires complex contacts. We provide internal deposition services for metals relevant to device physics, including Au, Pt, Pd, Ti, W, and Cu, allowing researchers to define specific contacts, microstrips, or interconnects directly on their diamond substrates.
High Thickness RequirementsThickness Flexibility (0.1”m to 10mm): We offer Single Crystal and Polycrystalline films ranging from 0.1”m to 500”m, and substrates up to 10mm thick, supporting both thin-film deposition and bulk material studies.

6CCVD’s in-house team of PhD material scientists and technical engineers is available to consult on material requirements for advanced projects, including the fabrication of diamond-based spintronic devices, chalcogenide heterostructures, and high-purity crystalline platforms. We assist with selecting the optimal diamond type (SCD vs. PCD), specifying necessary purity grades, and designing custom metalization layers.

For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly. We offer global shipping (DDU default, DDP available) for seamless delivery of critical materials worldwide.

View Original Abstract

The chalcogenide compound CuNbGaSe3, belonging to the system I-II-III-VI3, has been investigated by means of X-ray powder diffraction and its crystal structure has been refined by the Rietveld method.This is a material of the semiconductor type, which improves the properties of a simple semiconductor like CuGaSe2 because it ads spintronic applications due to its magnetic behavior. The powder pattern was composed by 94.2% of the principal phase CuNbGaSe3 and 5.8% of the secondary phase Cu0.667NbSe2. This material crystallizes with a CuFeInSe3-type structure in the tetragonal space group P4 2c (NÂș 112), unit cell parameters a = 5.6199(4) Å, c = 11.0275(2) Å, V = 348.28(4) Å3, with a normal adamantane-structure where occurs a degradation of symmetry from the chalcopyrite structure I4 2d to a related structure P4 2c.