A benchmark of co-flow and cyclic deposition/etch approaches for the selective epitaxial growth of tensile-strained Si:P. (31st August 2017)

• Record Type: Journal Article
• Authors: Hartmann, J M; Veillerot, M; Prévitali, B
• Is Part Of: Semiconductor science and technology. Volume 32:Number 10(2017:Oct.)
• Publication Date: 2017-08-31
• Subjects: Si:P raised sources and drains -- atmospheric pressure–chemical vapor deposition -- cyclic deposition/etch -- growth kinetics -- tensile strain -- in-situ doping and selectivity; 81.15.Gh -- 81.15.Aa -- 68.55.-a -- 61.72.uf; Semiconductors -- Periodicals; 621.38152
• DOI: 10.1088/1361-6641/aa82d4
• Languages: English
• ISSNs: 0268-1242

Abstract

Abstract: We have compared co-flow and cyclic deposition/etch processes for the selective epitaxial growth of Si:P layers. High growth rates, relatively low resistivities and significant amounts of tensile strain (up to 10 nm min −1, 0.55 mOhm cm and a strain equivalent to 1.06% of substitutional C in Si:C layers) were obtained at 700 °C, 760 Torr with a co-flow approach and a SiH2 Cl2 + PH3 + HCl chemistry. This approach was successfully used to thicken the sources and drains regions of n-type fin-shaped Field Effect Transistors. Meanwhile, the (Si2 H6 + PH3 /HCl + GeH4 ) CDE process evaluated yielded at 600 °C, 80 Torr even lower resistivities (0.4 mOhm cm, typically), at the cost however of the tensile strain which was lost due to (i) the incorporation of Ge atoms (1.5%, typically) into the lattice during the selective etch steps and (ii) a reduction by a factor of two of the P atomic concentration in CDE layers compared to that in layers grown in a single step (5 × 10 20 cm −3 compared to 10 21 cm −3 ).