Measurement of intensity of the second optical harmonic in heteroepitaxial cadmium-mercury telluride structures

Study of the Crystalline State of MBE (013)HgCdTe/CdTe/ZnTe/GaAs Heterostructure Layers by the Second Harmonic Generation Method

“…The SH polarization components dependence intensity on the mutual orientation of the polarization of excitation radiation in reference to the crystallophysical axes was measured, whereby the experiment recorded the SH polarization parallel to the azimuthally changing linear polarization of the excitation radiation (hereinafter referred to as the azimutal dependence). The experimental and numerical model data for the ideal crystal in a given local area were analyzed to obtain the quantitative information about the crystal state of the subsurface layer, its orientation and the growing layers orientation rotation within the plane and the growth direction, as well as a number of other characteristics with an error no worse one degree [26][27][28][29][34][35][36][37][38][39][40]. The crystal state of the MCT layers was measured by azimuthal SH signal intensity dependence measurement with layerby layer etching.…”

“…The GaAs substrate and the CdTe and ZnTe layers are transparent within the excitation radiation region ∼ 1 µm [37][38][39].…”

“…The second harmonic generation (SHG) is a faster and more convenient method in comparison with the electron and X-ray diffraction methods in the studies for obtaining the express non-destructive information, which supplements the application of traditional electron, X-ray and other diffraction methods [26][27][28][29][34][35][36][37][38][39][40].…”

Highly sensitive express nonlinear optical diagnostics of the crystalline state of heterostructures such as sphalerite

“…The dependence of SHG components polarization intensity on the mutual orientation of the exciting radiation polarization relative to the crystallophysical axes, when the SH polarization, parallel or perpendicular to the azimuthally varying linear polarization of the exciting radiation (further as the text goesangular or azimuthal dependence) is registered, allows obtaining quantitative information about the crystalline state of the surface layer, its orientation and several other properties while comparing experimental and model data in a given local area, to an accuracy less than or equal to a degree [1][2][3][4][5][6][7][8][9][10][11]. The diagnostic capabilities of the SHG method are widely used, for example, when studying the electronic and magnetic properties of materials by the characteristics the of identified magnetically induced second optic harmonic generation in diamagnetic and paramagnetic semiconductors [12,13].…”

“…Various research techniques detected multiple lattice damages and their link to the growth conditions [17][18][19][20][21]. Earlier studies using the second harmonic generation of probing radiation allowed determining the orientation and crystalline state of the layers in MCT MBE heteroepitaxial structure on (013)GaAs substrates, and demonstrated high efficiency of the SH method in experimental testing of high-quality heterostructures creation mode [9][10][11]. The data obtained allow predicting the application of the SHG method for investigating the quality of the consecutive stages of MBE-technology-based growing of MCT heteroepitaxial structure layers to determine the optimal conditions of the processes and requirements to the substrate.…”