Surface passivation for III-V materials integrated on silicon: analysis of surface recombination by second harmonic generation (SHG) and C-V measurements
Scientific context:
When integrating III-V materials onto silicon platforms, surface recombination is one of the main obstacles to the performance of future optoelectronic devices.
III-V surfaces and interfaces have a high density of electronic states that trap carriers, limiting the efficiency of integrated photodetectors and emitters.
Reducing these recombinations requires effective passivation processes adapted to III-V/Si heterostructures. Their evaluation relies on techniques that are sensitive to surface state: second harmonic generation (SHG), which is well suited for probing the quality of surfaces and interfaces, and C-V measurements on capacitive structures, which allow the density of surface states to be quantified.
Intership:
The internship focuses on the study of surface recombination and passivation optimisation. The objectives are:
To develop and apply different passivation processes (chemical and/or dielectric) specifically adapted to III-V surfaces.
Evaluate the effectiveness of treatments by analysing the evolution of surface recombination by SHG and extracting the surface state density and interface charges by C–V.
Correlate SHG signatures and electrical parameters in order to identify the most effective treatments.
Propose a technological process for optimal passivation of III-V materials on silicon.
Planned work:
Implementation of passivation processes (chemical treatments, deposits, annealing).
SHG characterisation of passivated surfaces and interfaces.
Fabrication/measurement of capacitances and extraction of C–V parameters.
Cross-analysis of SHG/CV to understand surface recombination mechanisms.
Synthesis of results and recommendations for passivation.
Required profile:
Master's degree or engineering school graduate with an interest in: semiconductors, characterisation (electrical and non-linear optical) of materials, clean room experimentation.
Duration: 6 months
Scientific context:
When integrating III-V materials onto silicon platforms, surface recombination is one of the main obstacles to the performance of future optoelectronic devices.
III-V surfaces and interfaces have a high density of electronic states that trap carriers, limiting the efficiency of integrated photodetectors and emitters.
Reducing these recombinations requires effective passivation processes adapted to III-V/Si heterostructures. Their evaluation relies on techniques that are sensitive to surface state: second harmonic generation (SHG), which is well suited for probing the quality of surfaces and interfaces, and C-V measurements on capacitive structures, which allow the density of surface states to be quantified.
Intership:
The internship focuses on the study of surface recombination and passivation optimisation. The objectives are:
To develop and apply different passivation processes (chemical and/or dielectric) specifically adapted to III-V surfaces.
Evaluate the effectiveness of treatments by analysing the evolution of surface recombination by SHG and extracting the surface state density and interface charges by C–V.
Correlate SHG signatures and electrical parameters in order to identify the most effective treatments.
Propose a technological process for optimal passivation of III-V materials on silicon.
Planned work:
Implementation of passivation processes (chemical treatments, deposits, annealing).
SHG characterisation of passivated surfaces and interfaces.
Fabrication/measurement of capacitances and extraction of C–V parameters.
Cross-analysis of SHG/CV to understand surface recombination mechanisms.
Synthesis of results and recommendations for passivation.
Required profile:
Master's degree or engineering school graduate with an interest in: semiconductors, characterisation (electrical and non-linear optical) of materials, clean room experimentation.
Duration: 6 months