Micro-contact printing of PEM thin films: effect of line tension and surface energies

RSC Advances ◽  
2015 ◽  
Vol 5 (64) ◽  
pp. 51891-51899 ◽  
Author(s):  
Meiyu Gai ◽  
Johannes Frueh ◽  
Agnes Girard-Egrot ◽  
Samuel Rebaud ◽  
Bastien Doumeche ◽  
...  

A theory and method for calculating printing resolution limits for microcontact printing of a condensed polyelectrolyte multilayer thin film, based on surface energies and line tension is presented.

2010 ◽  
Vol 11 ◽  
pp. 1-6 ◽  
Author(s):  
Sujira Promnimit ◽  
Joydeep Dutta

In this work, we report the directed self organization of multilayer thin film devices with colloidal nanoparticles through Layer-by-Layer (LbL) technique [1]. Self-organization of nanoparticles into assemblies to create novel nanostructures is getting increasing research attention in microelectronics, medical, energy and environmental applications. Directed self-organization of nanoparticles [2] into multilayer thin films were achieved by LbL growth through the interaction of oppositely charged of colloidal nanoparticles on substrates of any kind and shapes. Multilayer thin film devices were fabricated using multilayers of gold (conducting) nanoparticles separated by a dielectric nanoparticulate layer of zinc sulphide. The thin films obtained have been studied extensively and the changes in surface morphology, the optical absorption characteristics, thickness, uniformity, adhesion, and conduction behavior are reported. Current voltage (I-V) characteristics of multilayer devices with an increasing number of deposition cycles show an initial current blockade until an onset voltage value, which increases linearly upon the additional layers stacked in devices [3]. A conductive behavior of the device was observed upon exceeding the onset voltage. Moreover, I-V behavior showed that the conduction onset voltage increases linearly depending on the numbers of layers in the final device controlled by the deposition cycles. Systematic I-V characteristics in the forward and reverse biased conditions demonstrated rectifying behaviors in the onset of conduction voltage which makes these films attractive for future electronic device applications.


2004 ◽  
Vol 854 ◽  
Author(s):  
Peter M. Anderson ◽  
Jue Wang ◽  
Sridhar Narayanaswamy

ABSTRACTA 2D analytic result is presented for the penetration distance P of grain boundary grooves as a function of time t during heating and straining of polycrystalline multilayer thin films with immiscible phases. These grooves can ultimately pinch off individual layers. The result shows that P ∼ t0.25 initially and P ∼ t at longer time. This new analysis contrasts single- versus multilayer thin film response.


2005 ◽  
Vol 872 ◽  
Author(s):  
H.J. Yang ◽  
J.G. Lee ◽  
B. S. Cho ◽  
J. H. Lee ◽  
C. O. Jeong ◽  
...  

AbstractSelective deposition of Co thin films has been developed to produce Co pattern for TFT gate electrode on glass. We have been carried out by the selective growth of Co films with combination of micro-contact printing and metal organic chemical vapor deposition (MOCVD) at low temperature below 100°C. In the first step octadecyltrichlorosilane(OTS) layer with polydimethylsiloxane(PDMS) stamps was pre-patterned on glass. The patterned OTS area created a hydrophobic surface on glass which can prohibit nucleation and growth of Co films. In the second step a MOCVD Co selective deposition examined the difference of incubation time between OTS coated glass and pure glass.We optimized Co selective deposition through working pressure, deposition temperature, and gas flow rate ratio. Root mean square (rms) of Co films deposited on glass is 2nm enough to use gate electrode.OTS pattern was decomposed by UV treatment in the range of 280 and 350nm and then trilayer(n+Si/a-Si/SiNx) was continuously created on the sample which was selectively organized Co gate electrode on glass. We fabricated thin film transistor (TFT) of inverse staggered type using selectively deposited Co gate pattern. Reflectance was used to evaluate incubation time for Co deposition time and AFM was employed to confirm selectivity of Co thin film. The subthreshold slope and on/off current ratio was 0.88 V/decade and 6x106, respectively. The electron field-effect mobility at saturation was 0.35 cm2/Vs for Vd = 9V.


2001 ◽  
Vol 688 ◽  
Author(s):  
Ling Ling Sun ◽  
Wei Guo Liu ◽  
Ooi Kiang Tan ◽  
Wei Guang Zhu

AbstractA sol-gel derived Pb(Zr0.3Ti0.7)O3/PbTiO3 (PZT/PT) multilayer thin film structure has been studied for the application of infrared detection. Compared to the pure Pb(Zr0.3Ti0.7)O3 (PZT) thin film deposited by the same process, the multilayer thin film shows a lower dielectric constant and similar pyroelectric coefficient and dielectric loss. The detectivity figures of merit for the PZT/PT and PT thin films are 20.3×10−6 Pa-1/2 and 18.7×10−6 Pa−1/2, and values of voltage response figures of merit are 0.038 m2/C and 0.028 m2/C, respectively. The results show that the multilayer PZT/PT film is a better choice for pyroelectric infrared detection. Pyroelectric infrared detectors have been successfully developed based on the multilayer PZT/PT thin film. A silicon bulk-machined thermal isolation structure has been applied to reduce thermal loss from the sensing thin film to the Si substrate. To evaluate the detector performance and to aid in the thermal structure design, finite element analysis (FEA) of the detector in terms of heat transfer has been carried out by using a software package “ANSYS”. The detector response has been characterized by a modified Chynoweth system. At 7 Hz, the dynamic pyroelectric voltage responsivity is measured to be 108 V/W (in rms) with the sensing element size of 240×360 μm2. The measured results are consistent with the simulated results.


2014 ◽  
Vol 2 (38) ◽  
pp. 8012-8017 ◽  
Author(s):  
Ramphal Sharma ◽  
Gangri Cai ◽  
Dipak V. Shinde ◽  
Supriya A. Patil ◽  
Shaheed Shaikh ◽  
...  

We demonstrate meticulous fabrication of p-Cu2S/n-CdS heterojunction thin films using a facile wet-chemical approach.


Author(s):  
R. C. Moretz ◽  
G. G. Hausner ◽  
D. F. Parsons

Use of the electron microscope to examine wet objects is possible due to the small mass thickness of the equilibrium pressure of water vapor at room temperature. Previous attempts to examine hydrated biological objects and water itself used a chamber consisting of two small apertures sealed by two thin films. Extensive work in our laboratory showed that such films have an 80% failure rate when wet. Using the principle of differential pumping of the microscope column, we can use open apertures in place of thin film windows.Fig. 1 shows the modified Siemens la specimen chamber with the connections to the water supply and the auxiliary pumping station. A mechanical pump is connected to the vapor supply via a 100μ aperture to maintain steady-state conditions.


Author(s):  
M. Grant Norton ◽  
C. Barry Carter

Pulsed-laser ablation has been widely used to produce high-quality thin films of YBa2Cu3O7-δ on a range of substrate materials. The nonequilibrium nature of the process allows congruent deposition of oxides with complex stoichiometrics. In the high power density regime produced by the UV excimer lasers the ablated species includes a mixture of neutral atoms, molecules and ions. All these species play an important role in thin-film deposition. However, changes in the deposition parameters have been shown to affect the microstructure of thin YBa2Cu3O7-δ films. The formation of metastable configurations is possible because at the low substrate temperatures used, only shortrange rearrangement on the substrate surface can occur. The parameters associated directly with the laser ablation process, those determining the nature of the process, e g. thermal or nonthermal volatilization, have been classified as ‘primary parameters'. Other parameters may also affect the microstructure of the thin film. In this paper, the effects of these ‘secondary parameters' on the microstructure of YBa2Cu3O7-δ films will be discussed. Examples of 'secondary parameters' include the substrate temperature and the oxygen partial pressure during deposition.


Author(s):  
P. Lu ◽  
W. Huang ◽  
C.S. Chern ◽  
Y.Q. Li ◽  
J. Zhao ◽  
...  

The YBa2Cu3O7-x thin films formed by metalorganic chemical vapor deposition(MOCVD) have been reported to have excellent superconducting properties including a sharp zero resistance transition temperature (Tc) of 89 K and a high critical current density of 2.3x106 A/cm2 or higher. The origin of the high critical current in the thin film compared to bulk materials is attributed to its structural properties such as orientation, grain boundaries and defects on the scale of the coherent length. In this report, we present microstructural aspects of the thin films deposited on the (100) LaAlO3 substrate, which process the highest critical current density.Details of the thin film growth process have been reported elsewhere. The thin films were examined in both planar and cross-section view by electron microscopy. TEM sample preparation was carried out using conventional grinding, dimpling and ion milling techniques. Special care was taken to avoid exposure of the thin films to water during the preparation processes.


Sign in / Sign up

Export Citation Format

Share Document