Effect of MgO buffer layer thickness on the electrical properties of MgZnO thin film transistors fabricated by plasma assisted molecular beam epitaxy

One of the most common forms of cohesive failure observed in brittle thin film subjected to a tensile residual stress is channel cracking, a fracture mode in which through-film cracks propagate in the film. The crack growth rate depends on intrinsic film properties, residual stress, the presence of reactive species in the environments, and the precise film stack. In this paper, we investigate the effect of various buffer layers sandwiched between a brittle carbon-doped-silicate (CDS) film and a silicon substrate on channel cracking of the CDS film. The results show that channel cracking is enhanced if the buffer layer is more compliant than the silicon substrate. Crack velocity increases with increasing buffer layer thickness and decreasing buffer layer stiffness. This is caused by a reduction of the constraint imposed by the substrate on the film and a commensurate increase in energy release rate. The degree of constraint is characterized experimentally as a function of buffer layer thickness and stiffness, and compared to the results of a simple shear lag model that was proposed previously. The results show that the shear lag model does not accurately predict the effect of the buffer layer.

Download Full-text

The effect of Cr buffer layer thickness on voltage generation of thin-film thermoelectric modules

Journal of Micromechanics and Microengineering ◽

10.1088/0960-1317/23/11/115016 ◽

2013 ◽

Vol 23 (11) ◽

pp. 115016 ◽

Cited By ~ 7

Author(s):

Mizue Mizoshiri ◽

Masashi Mikami ◽

Kimihiro Ozaki

Keyword(s):

Thin Film ◽

Buffer Layer ◽

Layer Thickness ◽

Thermoelectric Modules ◽

Voltage Generation ◽

Buffer Layer Thickness

Download Full-text

Photovoltaic effect of ferroelectric Pb(Zr0.52,Ti0.48)O3 deposited on SrTiO3 buffered n-GaAs by laser molecular beam epitaxy

Functional Materials Letters ◽

10.1142/s1793604717500369 ◽

2017 ◽

Vol 10 (04) ◽

pp. 1750036 ◽

Cited By ~ 3

Author(s):

Yunxia Zhou ◽

Jun Zhu ◽

Xingpeng Liu ◽

Zhipeng Wu

Keyword(s):

Thin Film ◽

Molecular Beam Epitaxy ◽

Buffer Layer ◽

Molecular Beam ◽

Lattice Mismatch ◽

Photovoltaic Effect ◽

Short Circuit ◽

High Energy ◽

Text Type ◽

Laser Molecular Beam Epitaxy

Ferroelectric Pb(Zr[Formula: see text],Ti[Formula: see text]O3(PZT) thin film was grown on [Formula: see text]-type GaAs (001) substrate with SrTiO3 (STO) buffer layer by laser molecular beam epitaxy (L-MBE). The epitaxial process of the STO was in situ monitored by reflection high-energy electron diffraction (RHEED). The crystallographical growth orientation relationship was revealed to be (002) [Formula: see text] PZT//(002) [Formula: see text] STO//(001) [Formula: see text] GaAs by RHEED and X-ray diffraction (XRD). It was found that a small lattice mismatch between PZT and GaAs with a 45[Formula: see text] in-plane rotation relationship can be formed by inserting of a buffer layer STO. Besides, the enhanced electrical properties of the heterostructure were obtained with the short-circuit photocurrent increased to 52[Formula: see text]mA/cm2 and the better power conversation efficiency increased by 20% under AM1.5[Formula: see text]G (100[Formula: see text]mW/cm[Formula: see text] illumination. The work could provide a way for the application of this kind of heterostructure with high photocurrent response in optoelectronic thin film devices.

Download Full-text