InAs heteroepitaxial layer grown on GaAs (100) substrate is very meaningful in the field of optoelectronics, especially in the field of infrared detectors and lasers. InAs has some potential characteristics, such as high electron mobility and narrow energy gap, and many metals can be used as ohmic contacts of InAs, making it a very attractive material. PAM-XIAMEN provides heteroepitaxy growth of GaAs based InAs film, taking the following structure as an example. More heteroepitaxial nanostructures of GaAs from us please visit: https://www.powerwaywafer.com/gaas-wafers. In addition, we can provide epitaxial growth for the structure you need.
1. Heteroepitaxial Film of InAs
PAMP19169 – INASE
InAs thin film on GaAs substrate
|Epi||InAs, undoped||N type||–||1E16|
If you need to excite thin films of GaAs, InP, and InAs from the side of the substrate by using 523 nm laser light, you should consider absorption coefficient and thickness of the substrate. The substrate of each thin film should have low absorption coefficient to not lose a lot of photons that reach to the thin films or the thickness of the substrate should not be thick.
2. Heteroepitaxy Growth Process of InAs on GaAs
Due to the InAs on GaAs (100) substrate heteroepitaxy with large lattice mismatch (about 7%), the growth should follow the S-K mode.
That is, as the thickness of the growth layer increases gradually, the elastic distortion energy inside the crystal accumulates continuously. When the energy value exceeds a certain threshold, the two-dimensional layered crystal will collapse completely in a flash, leaving only a thin layer of growth layer (wetting layer) on the GaAs substrate surface. Under the combined action of surface energy, interface energy and distortion energy of the whole system, the rest of the InAs crystal materials will automatically re-aggregate on the surface of the wetting layer to form a three-dimensional dislocation-free crystal body “island” at nanometer scale.
To grow high-quality InAs epitaxial layer, you should pay attention to following points:
- Control the growth temperature. Too high temperature will cause the decomposition of InAs, which is difficult to grow, while too low temperature will make the surface of the epitaxial layer very rough. Generally, the growth temperature of InAs epitaxial layer is 480℃;
- V/III has great influence on the growth of InAs materials. InAs epitaxial layer with bright surface and high electron mobility can be grown while keeping In-rich and small V/III. Similarly, high quality InAs epitaxial layers can be grown while keeping As-rich and large V/III.
3. FAQ about Heteroepitaxy of InAs Thin Films
Q1: what is your opinion about the appropriate substrate to deposit thin films of InAs and GaAs on? I am using 1045 and 523 nm laser to excite thin films from the side of the substrate.
A: The appropriate substrate for depositing InAs and GaAs thin films is GaAs or InAs substrate.
Q2: Do I have to put a protective layer on InAs thin film during the dicing process?
A: Cut according to the cleavage surface of InAs/GaAs epitaxial wafer, not need protection.
Q3: In order to clean up the wafer after dicing process, what is the suitable procedure I should follow to avoid removing out the InAs film?
A: Clean the InAs hetero epitaxy wafer according to the sequence of acetone, ethanol and deionized water after cutting.
The Chinese government has announced new limits on the exportation of Gallium materials (such as GaAs, GaN, Ga2O3, GaP, InGaAs, and GaSb) and Germanium materials used to make semiconductor chips. Starting from August 1, 2023, exporting these materials is only allowed if we obtains a license from the Chinese Ministry of Commerce. Hope for your understanding and cooperation!