The analysis of threading dislocation density （TDD） in Ge-on-Si layer is critical for developing lasers, light emitting diodes （LEDs）, photodetectors （PDs）, modulators, waveguides, metal oxide semiconductor fiel...The analysis of threading dislocation density （TDD） in Ge-on-Si layer is critical for developing lasers, light emitting diodes （LEDs）, photodetectors （PDs）, modulators, waveguides, metal oxide semiconductor field effect transistors （MOSFETs）, and also the integration of Si-based monolithic photonics. The TDD of Ge epitaxial layer is analyzed by etching or transmission electron microscope （TEM）. However, high-resolution x-ray diffraction （HR-XRD） rocking curve provides an optional method to analyze the TDD in Ge layer. The theory model of TDD measurement from rocking curves was first used in zinc-blende semiconductors. In this paper, this method is extended to the case of strained Ge-on-Si layers. The HR-XRD 2θ/ω scan is measured and Ge （004） single crystal rocking curve is utilized to calculate the TDD in strained Ge epitaxial layer. The rocking curve full width at half maximum （FWHM） broadening by incident beam divergence of the instrument, crystal size, and curvature of the crystal specimen is subtracted. The TDDs of samples A and B are calculated to be 1.41108 cm-2 and 6.47108 cm-2, respectively. In addition, we believe the TDDs calculated by this method to be the averaged dislocation density in the Ge epitaxial layer.展开更多
High-quality AlN epitaxial layers with low dislocation densities and uniform crystal quality are essential for next-gener-ation optoelectronic and power devices.This study reports the epitaxial growth of 6-inch AlN fi...High-quality AlN epitaxial layers with low dislocation densities and uniform crystal quality are essential for next-gener-ation optoelectronic and power devices.This study reports the epitaxial growth of 6-inch AlN films on 17 nm AlN/sapphire tem-plates using metal-organic chemical vapor deposition(MOCVD).Comprehensive characterization reveals significant advance-ments in crystal quality and uniformity.Atomic force microscopy(AFM)shows progressive surface roughness reduction during early growth stages,achieving stabilization at a root mean square(RMS)roughness of 0.216 nm within 3 min,confirming suc-cessful 2D growth mode.X-ray rocking curve(XRC)analysis indicates a marked reduction in the(0002)reflection full width at half maximum(FWHM),from 445 to 96 arcsec,evidencing effective dislocation annihilation.Transmission electron microscopy(TEM)demonstrates the elimination of edge dislocations near the AlN template interface.Stress analysis highlights the role of a highly compressive 17 nm AlN template(5.11 GPa)in facilitating threading dislocation bending and annihilation,yielding a final dislocation density of~1.5×10^(7) cm^(-2).Raman spectroscopy and XRC mapping confirm excellent uniformity of stress and crystal quality across the wafer.These findings demonstrate the feasibility of this method for producing high-quality,large-area,atomically flat AlN films,advancing applications in optoelectronics and power electronics.展开更多
基金Project supported by the Research Plan in Shaanxi Province,China(Grant No.2016GY-085)the Opening Project of Key Laboratory of Microelectronic Devices&Integrated Technology,Institute of Microelectronics,Chinese Academy of Sciences(Grant No.90109162905)+1 种基金the Fundamental Research Funds for the Central Universities(Grant No.17-H863-04-ZT-001-019-01)the National Natural Science Foundation of China(Grant Nos.61704130 and 61474085)
文摘The analysis of threading dislocation density （TDD） in Ge-on-Si layer is critical for developing lasers, light emitting diodes （LEDs）, photodetectors （PDs）, modulators, waveguides, metal oxide semiconductor field effect transistors （MOSFETs）, and also the integration of Si-based monolithic photonics. The TDD of Ge epitaxial layer is analyzed by etching or transmission electron microscope （TEM）. However, high-resolution x-ray diffraction （HR-XRD） rocking curve provides an optional method to analyze the TDD in Ge layer. The theory model of TDD measurement from rocking curves was first used in zinc-blende semiconductors. In this paper, this method is extended to the case of strained Ge-on-Si layers. The HR-XRD 2θ/ω scan is measured and Ge （004） single crystal rocking curve is utilized to calculate the TDD in strained Ge epitaxial layer. The rocking curve full width at half maximum （FWHM） broadening by incident beam divergence of the instrument, crystal size, and curvature of the crystal specimen is subtracted. The TDDs of samples A and B are calculated to be 1.41108 cm-2 and 6.47108 cm-2, respectively. In addition, we believe the TDDs calculated by this method to be the averaged dislocation density in the Ge epitaxial layer.
基金supported by National Key R&D Program of China(2022YFB3605100)the National Science Fund for Distinguished Young Scholars of China(62425408)+5 种基金the National Natural Science Foundation of China(62204241,U22A2084,and 62121005)Key Research and Development Projects of Jilin Provincial Science and Technology Development Plan(20240302027GX)the Natural Science Foundation of Jilin Province(20230101345JC,20230101360JC,20230101107JC)the Youth Innovation Promotion Association of CAS(2023223)the Young Elite Scientist Sponsorship Program By CAST(YESS20200182)the CAS Talents Program.
文摘High-quality AlN epitaxial layers with low dislocation densities and uniform crystal quality are essential for next-gener-ation optoelectronic and power devices.This study reports the epitaxial growth of 6-inch AlN films on 17 nm AlN/sapphire tem-plates using metal-organic chemical vapor deposition(MOCVD).Comprehensive characterization reveals significant advance-ments in crystal quality and uniformity.Atomic force microscopy(AFM)shows progressive surface roughness reduction during early growth stages,achieving stabilization at a root mean square(RMS)roughness of 0.216 nm within 3 min,confirming suc-cessful 2D growth mode.X-ray rocking curve(XRC)analysis indicates a marked reduction in the(0002)reflection full width at half maximum(FWHM),from 445 to 96 arcsec,evidencing effective dislocation annihilation.Transmission electron microscopy(TEM)demonstrates the elimination of edge dislocations near the AlN template interface.Stress analysis highlights the role of a highly compressive 17 nm AlN template(5.11 GPa)in facilitating threading dislocation bending and annihilation,yielding a final dislocation density of~1.5×10^(7) cm^(-2).Raman spectroscopy and XRC mapping confirm excellent uniformity of stress and crystal quality across the wafer.These findings demonstrate the feasibility of this method for producing high-quality,large-area,atomically flat AlN films,advancing applications in optoelectronics and power electronics.
