Berlin 2018 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
HL: Fachverband Halbleiterphysik
HL 50: HL Poster IV
HL 50.36: Poster
Thursday, March 15, 2018, 19:00–21:00, Poster B
Structure and chemistry of crystalline silicon-aluminum oxide interfaces — •Arne Ahrens and Michael Seibt — Georg-August University Göttingen, 4th Physical Institute, Göttingen, Germany
Aluminum oxide deposited on crystalline silicon by atomic layer deposition (ALD) is known for its high surface passivation capabilities. This surface passivation is attributed to a high negative fixed charge density of about -4×1012 cm−2[1] in the aluminum oxide layer close to the silicon-aluminum oxide interface [2]. This makes aluminum oxide an interesting material to increase the efficiency of solar cells by passivation of surface states. The high surface passivation capability of aluminum oxide on silicon changes and can even be improved due to UV irradiation depending on the temperature treatment [3], which is used to activate the surface passivation.
In this work, we apply transmission electron microscopy (TEM) and electron energy loss spectroscopy (EELS) to study the structure and chemistry of the interface of aluminum oxide deposited by atomic layer deposition (ALD) and crystalline silicon subjected to different processing schemes. Here, we focus on the effect of post-deposition heat treatments and the effect of the UV irradiation.
[1] F. Werner and J. Schmidt, Appl. Phys.Lett Vol.104, 091604 (2014). [2] B. Hoex et al., J. Appl. Phy. Vol.104, 113703 (2008). [3] B. Veith-Wolf et al., Photovoltaic Specialists Conference (PVSC), 2016 IEEE 43rd, 16483697