Growth Uniformity in Selective Area Epitaxy of AlGaN/GaN Heterostructures for the Application in Semiconductor Devices
The design of modern semiconductor devices often requires the fabrication of three-dimensional (3D) structures to integrate microelectronic components with photonic, micromechanical, or sensor systems within one semiconductor substrate. It is a technologically challenging task, as a strictly defined...
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MDPI AG
2020-12-01
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| Series: | Electronics |
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| Online Access: | https://www.mdpi.com/2079-9292/9/12/2129 |
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| author | Michał Stępniak Mateusz Wośko Joanna Prażmowska-Czajka Andrzej Stafiniak Dariusz Przybylski Regina Paszkiewicz |
| author_facet | Michał Stępniak Mateusz Wośko Joanna Prażmowska-Czajka Andrzej Stafiniak Dariusz Przybylski Regina Paszkiewicz |
| author_sort | Michał Stępniak |
| collection | DOAJ |
| description | The design of modern semiconductor devices often requires the fabrication of three-dimensional (3D) structures to integrate microelectronic components with photonic, micromechanical, or sensor systems within one semiconductor substrate. It is a technologically challenging task, as a strictly defined profile of the device structure is obligatory. This can be achieved either by chemical etching or selective deposition on a masked substrate. In this paper, the growth uniformity of AlGaN/GaN heterostructures during selective-area metalorganic vapour-phase epitaxy (SA-MOVPE) was studied. Such structures are typically used in order to fabricate high-electron-mobility transistors (HEMT). The semiconductor material was deposited through 200 μm long stripe-shaped open windows in a SiO<sub>2</sub> mask on GaN/sapphire templates. The window width was varied from 5 μm to 160 μm, whereas mask width separating particular windows varied from 5 μm to 40 μm. The experiment was repeated for three samples differing in GaN layer thickness: 150 nm, 250 nm, and 500 nm. Based on theoretical models of the selective growth, a sufficiently uniform thickness of epitaxially grown AlGaN/GaN heterostructure has been achieved by selecting the window half-width that is smaller than the diffusion length of the precursor molecules. A Ga diffusion length of 15 μm was experimentally extracted by measuring the epitaxial material agglomeration in windows in the dielectric mask. Measurements were conducted while using optical profilometry. |
| first_indexed | 2024-03-10T14:07:21Z |
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| institution | Directory Open Access Journal |
| issn | 2079-9292 |
| language | English |
| last_indexed | 2024-03-10T14:07:21Z |
| publishDate | 2020-12-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Electronics |
| spelling | doaj.art-eb6a916123be443b87f1c489c13d59692023-11-21T00:32:35ZengMDPI AGElectronics2079-92922020-12-01912212910.3390/electronics9122129Growth Uniformity in Selective Area Epitaxy of AlGaN/GaN Heterostructures for the Application in Semiconductor DevicesMichał Stępniak0Mateusz Wośko1Joanna Prażmowska-Czajka2Andrzej Stafiniak3Dariusz Przybylski4Regina Paszkiewicz5Faculty of Microsystem Electronics and Photonics, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, PolandFaculty of Microsystem Electronics and Photonics, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, PolandFaculty of Microsystem Electronics and Photonics, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, PolandFaculty of Microsystem Electronics and Photonics, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, PolandFaculty of Microsystem Electronics and Photonics, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, PolandFaculty of Microsystem Electronics and Photonics, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, PolandThe design of modern semiconductor devices often requires the fabrication of three-dimensional (3D) structures to integrate microelectronic components with photonic, micromechanical, or sensor systems within one semiconductor substrate. It is a technologically challenging task, as a strictly defined profile of the device structure is obligatory. This can be achieved either by chemical etching or selective deposition on a masked substrate. In this paper, the growth uniformity of AlGaN/GaN heterostructures during selective-area metalorganic vapour-phase epitaxy (SA-MOVPE) was studied. Such structures are typically used in order to fabricate high-electron-mobility transistors (HEMT). The semiconductor material was deposited through 200 μm long stripe-shaped open windows in a SiO<sub>2</sub> mask on GaN/sapphire templates. The window width was varied from 5 μm to 160 μm, whereas mask width separating particular windows varied from 5 μm to 40 μm. The experiment was repeated for three samples differing in GaN layer thickness: 150 nm, 250 nm, and 500 nm. Based on theoretical models of the selective growth, a sufficiently uniform thickness of epitaxially grown AlGaN/GaN heterostructure has been achieved by selecting the window half-width that is smaller than the diffusion length of the precursor molecules. A Ga diffusion length of 15 μm was experimentally extracted by measuring the epitaxial material agglomeration in windows in the dielectric mask. Measurements were conducted while using optical profilometry.https://www.mdpi.com/2079-9292/9/12/2129selective area growthselective epitaxyAlGaN/GaN heterostructuresgallium nitrideedge effectseffective diffusion length |
| spellingShingle | Michał Stępniak Mateusz Wośko Joanna Prażmowska-Czajka Andrzej Stafiniak Dariusz Przybylski Regina Paszkiewicz Growth Uniformity in Selective Area Epitaxy of AlGaN/GaN Heterostructures for the Application in Semiconductor Devices Electronics selective area growth selective epitaxy AlGaN/GaN heterostructures gallium nitride edge effects effective diffusion length |
| title | Growth Uniformity in Selective Area Epitaxy of AlGaN/GaN Heterostructures for the Application in Semiconductor Devices |
| title_full | Growth Uniformity in Selective Area Epitaxy of AlGaN/GaN Heterostructures for the Application in Semiconductor Devices |
| title_fullStr | Growth Uniformity in Selective Area Epitaxy of AlGaN/GaN Heterostructures for the Application in Semiconductor Devices |
| title_full_unstemmed | Growth Uniformity in Selective Area Epitaxy of AlGaN/GaN Heterostructures for the Application in Semiconductor Devices |
| title_short | Growth Uniformity in Selective Area Epitaxy of AlGaN/GaN Heterostructures for the Application in Semiconductor Devices |
| title_sort | growth uniformity in selective area epitaxy of algan gan heterostructures for the application in semiconductor devices |
| topic | selective area growth selective epitaxy AlGaN/GaN heterostructures gallium nitride edge effects effective diffusion length |
| url | https://www.mdpi.com/2079-9292/9/12/2129 |
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