Femtosecond Laser-Induced Micro-Structuring of Thin a-Si:H Films

2004 ◽  
Vol 850 ◽  
Author(s):  
Barada K. Nayak ◽  
Mool C. Gupta

ABSTRACTIn a-Si:H solar cells, light trapping has been sought as a method to enhance absorption and improve the efficiencies of these devices. Here we present results for surface texturing of 2μm thick a-Si:H films by 800 nm wavelength femtosecond laser. The texture led to a significant enhancement in optical absorption (80%) in visible through near IR (60%). The textured surface was examined by a scanning electron microscope (SEM) and atomic force microscope (AFM). The results indicated the formation of dense spikes with height of 65–75 nm. The samples were completely black after femtosecond laser treatment.

2022 ◽  
Author(s):  
Sanjeev Kumar Kanth ◽  
Anjli Sharma ◽  
Byong Chon Park ◽  
Woon Song ◽  
Hyun Rhu ◽  
...  

Abstract We have constructed a new nanomanipulator (NM) in a field emission scanning electron microscope (FE-SEM) to fabricate carbon nanotube (CNT) tip to precisely adjust the length and attachment angle of CNT onto the mother atomic force microscope (AFM) tip. The new NM is composed of 2 modules, each of which has the degree of freedom of three-dimensional rectilinear motion x, y and z and one-dimensional rotational motion θ. The NM is mounted on the stage of a FE-SEM. With the system of 14 axes in total which includes 5 axes of FE-SEM and 9 axes of nano-actuators, it was possible to see CNT tip from both rear and side view about the mother tip. With the help of new NM, the attachment angle error could be reduced down to 0º as seen from both the side and the rear view, as well as, the length of the CNT could be adjusted with the precision using electron beam induced etching. For the proper attachment of CNT on the mother tip surface, the side of the mother tip was milled with focused ion beam. In addition, electron beam induced deposition was used to strengthen the adhesion between CNT and the mother tip. In order to check the structural integrity of fabricated CNT, transmission electron microscope image was taken which showed the fine cutting of CNT and the clean surface as well. Finally, the performance of the fabricated CNT tip was demonstrated by imaging 1-D grating and DNA samples with atomic force microscope in tapping mode.


2009 ◽  
Vol 1 (1) ◽  
pp. 50-58 ◽  
Author(s):  
Ita Junkar ◽  
Vid Sustar ◽  
Mojca Frank ◽  
Vid Jansa ◽  
Apolonija Bedina Zavec ◽  
...  

2007 ◽  
Vol 121-123 ◽  
pp. 739-742 ◽  
Author(s):  
H.M. Chi ◽  
Z.D. Xiao ◽  
Xin Xing Xiao

Weng`an fauna in Guizhou, China provides a unique window for the evolution of the early life especially since the animal embryos and sponge is found there. Phosphatization makes the fossils preserve in details including cells and subcellular structure. Here we use atomic force microscope observing the surface of some three dimensional preserved embryo fossils and the ultra membrane-like structure is found under atomic force microscope (AFM) while such structure can`t be found under scanning electron microscope (SEM). The membrane-like structure is approximately 10nm in thickness which maybe one part of the fossil embryos or belong to another nano scale microfossils. Therefore, AFM provides a new method for the study of the ultra structure of the microfossils from Weng`an fauna.


2004 ◽  
Vol 16 (2) ◽  
pp. 155-162 ◽  
Author(s):  
Masahiro Nakajima ◽  
◽  
Fumihito Arai ◽  
Lixin Dong ◽  
Toshio Fukuda

A method is presented for pico-Newton (pN) order force measurement using a carbon nanotube (CNT) probe, which is calibrated by electromechanical resonance. A CNT probe is constructed by attaching a CNT to the end of a tungsten needle or an atomic force microscope (AFM) cantilever using nanorobotic manipulators inside a field-emission scanning electron microscope (FE-SEM). Conductive electron-beam-induced deposition (EBID) is used for the fixation of CNTs with an internal vaporized precursor W(CO)6. For manipulating them easily and quickly, CNTs are dispersed in ethanol by ultrasonic waves and oriented on copper electrodes by electrophoresis. The elastic moduli of CNT probes are calibrated for use as a force measurement probe by electrically exciting at fundamental frequency. We analyzed the resolution of force measurement using a CNT probe. This force measurement can be used to characterize the mechanical properties of nanostructures and to measure friction or exfoliation forces in nanometer order.


2020 ◽  
Vol 34 (17) ◽  
pp. 2050155
Author(s):  
Naiyuan Cui ◽  
Fei Wang ◽  
Hanyuan Ding ◽  
Lei Guo

Diamond etching of [Formula: see text] orientation is processed in chemical vapor deposition (CVD) chamber using H2 as reactive gas. Etching process happens on diamond substrates using a variety of etch mask materials including copper and nickel. Scanning electron microscope (SEM) and atomic force microscope (AFM) show different kinds of diamond etching pattern of two mask materials. It is observed that the etching pit of copper is tetrahedron, while the etching pit of nickel is step structure. This indicates diverse etching mechanism of diamond etched by different metal. Observing the surface etching topography of diamond and analyzing the etching mechanism of different metal can help study the growth of diamond by CVD and controllable etching of diamond.


2012 ◽  
Vol 557-559 ◽  
pp. 1322-1325 ◽  
Author(s):  
Yi He Li ◽  
Hua Xiao ◽  
Gong Yi Li ◽  
Jian Feng ◽  
Xiao Dong Li

A novel femtosecond laser directly writing method was utilized to fabricate microchannels on silicon carbide (SiC) substrate. The micro patterns were transferred to a Polydimethylsiloxane (PDMS) stamp, characterized by both optical microscope and scanning electron microscope (SEM). The relationship between size (depth and width) of channels and power of laser pulse were discussed in detail.


2012 ◽  
Vol 622-623 ◽  
pp. 361-365 ◽  
Author(s):  
Vikas Upadhyay ◽  
P.K. Jain ◽  
N.K. Mehta

This work presents the influence of workpiece preheat temperatures on the machinability of Ti-6Al-4V alloy and chip formation. Machinability has been studied in terms of cutting forces, surface roughness and tool wear. Influence of preheat temperatures on chip morphology and roughness of chip back surface has been studied using scanning electron microscope and atomic force microscope respectively to get better insight of tribology at tool-chip interface. Based on overall observations, preheat temperature of 300 0C was found as the most appropriate parameter.


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