Loading effect in SiGe layers grown by dichlorosilane- and silane-based epitaxy

Abstract

The evolution of the loading effect in Si1−xGex layers (0⩽x⩽20%) versus growth parameters has been investigated for selective and nonselective growth using silane- and dichlorosilane-based epitaxy. Various methods have been examined in order to reduce the loading effect, and their influence on the defect density will be further discussed. High-resolution x-ray diffraction and atomic force microscopy were applied as the main tools in these investigations. It is shown that SiGe epitaxy is strongly sensitive to the opening size on the patterned substrates. This dependence is affected by the chemistry of the deposition. This effect can be decreased by adding HCl to the gas mixture or decreasing the growth rate. Meanwhile, adding HCl during the growth of SiGe layers or using a low growth rate decreases the epitaxial quality of the layers. Depositing a Si seed layer prior to the growth of the SiGe layer reduces the loading effect without degrading the epitaxial quality of the layer.

Selective epitaxial growth of stepwise SiGe:B at the recessed sources and drains: A growth kinetics and strain distribution study

“…25,26 However, other factors such as chemical and thermal effects led to growth rate differences between the bulk and patterned wafers. [27][28][29] The cross-sectional TEM images after selected process cycles are shown in Fig. 3.…”

Pattern Dependency and Loading Effect of Pure-Boron-Layer Chemical-Vapor Deposition

“…[8][9][10][11] Here the PureB-layer was deposited at both atmospheric (ATM) and 60 torr on several patterned wafers with ∼80% OCR and opening areas of 100 mm 2 , 200 mm 2 , 300 mm 2 and 400 mm 2 at atmospheric (ATM) and 60 torr. Deposition was performed with different diborane partial pressures and carrier gas flows which P 1 (F 1 ) is the maximum diborane partial pressure (main flow) and P 2 (F 2 ) and P 3 (F 3 ) are 75% and 50% of the maximum values.…”

“…In this paper we focus on determining the global effects that can be determined on large area windows by using measurement techniques such as SIMS or ellipsometry. While several methods have been proposed to decrease the pattern dependency and/or loading effect for SEG of the Si and SiGe, [8][9][10][11] this is the first report on the reproducibility and the pattern dependency including loading effects of the PureB Deposition. An optimization of the deposition parameters is performed for 700…”

Pattern Dependency of Pure-Boron-Layer Chemical-Vapor Depositions

“…In this way an increase of the amount of oxide area around the window will result in an increase in the PureB-layer thickness. , 45 (6) 39-48 (2012) Impact of deposition parameters on pattern dependency A series of reports on SEG of Si and SiGe, have shown that the pattern dependency can be reduced by tuning the growth parameters (8)(9)(10). Here the PureB-layer was deposited at both atmospheric pressure (ATM) and 60 torr on several patterned wafers with ∼80% OCR and opening areas of 100 mm 2 , 200 mm 2 , 300 mm 2 and 400 mm 2 at atmospheric pressure (ATM) and 60 torr.…”

“…While several methods have been proposed to decrease the pattern dependency and/or loading effect for SEG of the Si and SiGe (8)(9)(10), this is the first report on the reproducibility and the pattern dependency including loading effects of the PureB depositions. An optimization of the deposition parameters is performed for 700ºC depositions, at either atmospheric (ATM) pressure or 60 torr, with respect to uniformity over the wafer with and without a patterned oxide coverage.…”