HF-Last Wet Clean in Combination with a Low Temperature GeH4-Assisted HCl In Situ Clean Prior to Si0.8Ge0.2-on-Si Epitaxial Growth

Kurt Wostyn; Sathish K. Dhayalan; Andriy Hikavyy; Roger Loo; Bastien Douhard; Alain Moussa; Dirk Rondas; Karine Kenis; Paul W. Mertens; Frank Holsteyns; Stefan De Gendt; Harald B. Profijt

doi:10.4028/www.scientific.net/SSP.219.20

Paper Titles

Preface, Committee and Acknowledgement

Necessity of Cleaning and its Application in Future Memory Devices
p.3

Removal of Interfacial Layer in HfO₂ Gate Stack by Post-Gate Cleaning Using NF₃/NH₃ Dry Cleaning Technique
p.11

Catalyst Assisted Low Temperature Pre Epitaxial Cleaning for Si and SiGe Surfaces
p.16

HF-Last Wet Clean in Combination with a Low Temperature GeH₄-Assisted HCl In Situ Clean Prior to Si_0.8Ge_0.2-on-Si Epitaxial Growth
p.20

Retardation Phenomenon of Oxide Removal during the Formation of Dual Gate Oxide via PR-Mask Wet Etching
p.24

Aluminum Reduction in SC1
p.28

Metal Removal Efficiency in Deep Submicron Trenches by Wet Chemicals
p.32

Impact of Surface Treatment of Si₃N₄ on Subsequent SiO₂ Deposition
p.36

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HF-Last Wet Clean in Combination with a Low Temperature GeH₄-Assisted HCl In Situ Clean Prior to Si_0.8Ge_0.2-on-Si Epitaxial Growth

Abstract:

Epitaxial growth requires a clean starting surface for the growth of a high-quality crystalline layer. For epitaxy on Si, an HF-last wet clean followed by an in-situ high-temperature hydrogen bake is the reference pre-epi clean sequence to obtain an oxygen-free surface [1, 2]. The temperature required to remove all residual oxygen also makes the surface atoms mobile, resulting in reflow. The high temperatures used during the H₂-bake can also result in intolerable doping profile changes. A lower temperature pre-epi clean sequence is required to avoid this reflow, especially when moving away from Si. In addition the high temperatures needed during a H₂-bake would result in the relaxation of high mobility channels, e.g. strained Si_1-xGe_x or III-V materials [3]. Several low temperatures pre-epi cleaning solutions have been proposed in the past, e.g. GeH₄-assisted H₂-bake [4] or more recently, a GeH₄-assisted HCl clean [5]. In this study we looked at the interaction between HF-last wet clean and the in-situ GeH₄-assisted HCl clean prior to Si_0.8Ge_0.2-on-Si epitaxy.