On the mechanism of the hydrogen-induced exfoliation of silicon

We have performed systematic measurements of the splitting kinetics induced by H-only and He + H sequential ion implantation into relaxed Si 0.8 Ge 0.2 layers and compared them with the data obtained in Si. For H-only implants, Si splits faster than Si 0.8 Ge 0.2 . Sequential ion implantation leads to faster splitting kinetics than H-only in both materials and is faster in Si 0.8 Ge 0.2 than in Si. We have performed secondary ion mass spectrometry, Rutherford backscattering spectroscopy in channeling mode, and transmission electron microscopy analyses to elucidate the physical mechanisms involved in these splitting phenomena. The data are discussed in the framework of a simple phenomenological model in which vacancies play an important role.

Section: Discussionmentioning

confidence: 99%

Splitting kinetics of Si0.8Ge0.2 layers implanted with H or sequentially with He and H

Nguyen

Bourdelle

Aulnette

et al. 2008

“…Vacancies have been proposed as a mechanism by which hydrogen platelets nucleate and grow in ioncut processing. 37,38 In extrinsic silicon, vacancies have an associated charge state. 5 Charged species can be influenced by electric fields.…”

Section: Microwave Enhancement In Ion-cut Fabricationmentioning

confidence: 99%

Microwave enhanced ion-cut silicon layer transfer

Thompson¹,

Alford²,

Mayer³

et al. 2007

Polycrystalline silicon layer transfer by ion-cut Appl. Phys. Lett. 82, 1544Lett. 82, (2003 Microwave heating has been used to decrease the time required for exfoliation of thin single-crystalline silicon layers onto insulator substrates using ion-cut processing. Samples exfoliated in a 2.45 GHz, 1300 W cavity applicator microwave system saw a decrease in incubation times as compared to conventional anneal processes. Rutherford backscattering spectrometry, cross sectional scanning electron microscopy, cross sectional transmission electron microscopy, and selective aperture electron diffraction were used to determine the transferred layer thickness and crystalline quality. The surface quality was determined by atomic force microscopy. Hall measurements were used to determine electrical properties as a function of radiation repair anneal times. Results of physical and electrical characterizations demonstrate that the end products of microwave enhanced ion-cut processing do not appreciably differ from those using more traditional means of exfoliation.

“…22 The governing equation for excess pressure in a cavity, relative to ambient pressure, can be written as…”

Section: A Thermodynamics Of Cavity Nucleationmentioning

confidence: 99%

Nanomechanical characterization of cavity growth and rupture in hydrogen-implanted single-crystal BaTiO3

Park

Nardi

et al. 2005

A thermodynamic model of cavity nucleation and growth in ion-implanted single-crystal BaTiO 3 layer is proposed, and cavity formation is related to the measured mechanical properties to better understand hydrogen implantation-induced layer transfer processes for ferroelectric thin films. The critical radius for cavity nucleation was determined experimentally from blistering experiments performed under isochronal anneal conditions and was calculated using continuum mechanical models for deformation and fracture, together with thermodynamic models. Based on thermodynamic modeling, we suggest that cavities grow toward the cracking criteria at a critical blister size whereupon gas is emitted from ruptured cavities. The main driving force for layer splitting is the reduction of the overall elastic energy stored in the implanted region during the cavity nucleation and growth as the gaseous H 2 entrapped within the cavities is released. Nanoindentation measurements reveal locally the mechanical property changes within the vicinity of a single cavity. Using the measured mechanical properties at the single-cavity level, we developed three-dimensional strain and stress profiles using finite element method.