研究目的
To structurally and chemically characterize InGaN thin films and InN quantum dots grown on Si and InGaN substrates using (S)TEM techniques to improve fabrication processes.
研究成果
The (S)TEM characterization confirmed single-crystalline and homogeneous InGaN films across the compositional range, with epitaxial growth of InN QDs. Various defects were identified, and the techniques provided insights for optimizing growth recipes to improve material quality for optoelectronic applications.
研究不足
The high density of threading dislocations in localized areas impeded reliable quantification. The amorphous SiNx interlayer formed during ion-milling was unavoidable. Some defects like phase separations and cubic inclusions were highly localized and not representative of the general quality.
1：Experimental Design and Method Selection:
The study employed various (S)TEM techniques including CTEM, HRTEM, HAADF imaging, SAED, and EDX to analyze InGaN/Si heterostructures and InN QDs.
2：Sample Selection and Data Sources:
Four samples with In-containing nitride structures were prepared, including InGaN layers and InN QDs grown by PA-MBE, SK, and DE methods on Si (111) substrates.
3：List of Experimental Equipment and Materials:
TEM samples were prepared using mechanical grinding, polishing, and ion-milling with a GATAN PIPS-691 system. Microscopes used: JEOL 1200EX, JEOL 2100 LaB6, JEOL 2010, and FEI Titan Cubed Themis 60-
4：Experimental Procedures and Operational Workflow:
3 Cross-section and planar-view specimens were prepared, thinned to electron-transparency, and observed under different TEM conditions to obtain images and diffraction patterns.
5：Data Analysis Methods:
Data were analyzed using techniques such as FFT for HRTEM images, Vegard's Law for composition calculation from SAED patterns, and statistical analysis of EDX spectra.
独家科研数据包，助您复现前沿成果，加速创新突破
获取完整内容
