In terms of the lattice parameters and miller indices? and how can I identify whether a material is heterojunction or heterostructure? and which characterization method is useful to know whether it is a heterostructure or heterojunction?
Typically, people refer to the active region of a laser as a double heterostructure: a small gap material cladded by wide gap layers. This acts to concentrate carriers and produce gain.
A heterojunction typically refers to a single boundary between materials of two different bandgaps. Heterojunctions can be of many types (a laser double heterostructure uses a type I alignment), organic solar cells use type II alignment, and some kinds of transistors could use type III alignment.
Drisya, heterojunction is the single contact between the different materials. Heterostructure is the composite structure that could consist of the several heterojunctions, e.g. 2 for the double geterojunction quantum well AlGaAs/GaAs/AlGaAs; about 10 for composite channel HEMT (high electron mobility transistor) structure and about thousand for Quantum Cascade Laser heterostructures. So it isn't principal difference but terminology of single constituent for heterojunction and functional material for heterostructure. Both can be characterized by huge variety of structural or optical techniques as HRTEM ( high resolution transmittance electron microscopy), XRD (X-ray diffractometry), RBS (Rutherford ion backscattering), PL (photolumnescence spectroscopy), spectral ellipsometry (in some cases) and other techniques).
Good luck!
One can go for optical characterization too. Heterojunction/structure may have Photovoltaic properties.
SCS-4200 can be helpful for I-V and C-V.
Heterojunction is the interface between two different bandgap materials. For example: the interface between CdS/CIGS is called hetero junction. Note: CdS and CIGS have the bandgap of 2.4eV and 1.7eV respectively.
While hetero structure is a material system of different bandgap materials. That means it can consists of several hetero junctions.
For example: the material system consisting ZnO/CdS/CIGS/Mo is hetero structure, there ZnO, CdS, CIGS and Mo are different bandgap materials.
I hope that you help :) For more info you can read
Semiconductor Optoelectronic Devices (2nd Edition) by Pallab Bhattacharya
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