Nanofluidic Channel Fabrication and Characterization by Micromachining

2003 ◽  
Author(s):  
Wan-Sik Kim ◽  
Junghoon Lee ◽  
Rodney S. Ruoff
Keyword(s):  
Selective Oxidation ◽  
Metallic Oxide ◽  
Force Microscopy ◽  
Wafer Fusion ◽  
Fusion Bonding ◽  
Atomic Force ◽  
High Temperature Anneal ◽  
Wafer Pair ◽  
Silicon Cmos ◽  
Microfabrication Techniques

The well-established microfabrication techniques of complementary metallic oxide silicon (CMOS) selective oxidation and wafer-wafer fusion bonding were used to fabricate sub-micrometer silicon fluidic channels as small as 30 nm between extremely thin SiO2 top and bottom layers of 30 nm thicknesses. Trenches a few tens of nanometer deep were patterned in 10-cm diameter Si wafers by selective oxidation and their depth measured by atomic force microscopy (AFM); the AFM measured depths showed that the trench depth could be controlled to nanometer resolution. The resolution of the photolithography employed determined the trench width resolution. Nanochannels were formed with direct wafer-wafer fusion bonding. Channels of 30-nm depth or greater between the bonded wafer pair were nondestructively detected by a simple infrared (IR) image system; channels less than this depth collapsed for the overall channel geometry employed. Thus the nanofluidic structures survived the pressure and high temperature anneal of wafer bonding. Experimental results agree well with a theoretical prediction for which depths nanochannels would collapse.

Non Destructive Determination of the Threading Dislocation Density of Smooth Simox Substrates using Atomic Force Microscopy

2000 ◽  
Vol 6 (S2) ◽  
pp. 1088-1089
Author(s):  
A. Domenicucci ◽  
R. Murphy ◽  
D. Sadanna ◽  
S. Klepeis
Keyword(s):  
Atomic Force Microscopy ◽  
High Temperature ◽  
Single Crystal Silicon ◽  
Silicon Layer ◽  
High Dose ◽  
Threading Dislocation ◽  
Crystal Silicon ◽  
Force Microscopy ◽  
Atomic Force ◽  
High Temperature Anneal

Atomic force microscopy (AFM) has been used extensively in recent years to study the topographic nature of surfaces in the nanometer range. Its high resolution and ability to be automated have made it an indispensable tool in semiconductor fabrication. Traditionally, AFM has been used to monitor the surface roughness of substrates fabricated by separation by implanted oxygen (SIMOX) processes. It was during such monitoring that a novel use of AFM was uncovered.A SIMOX process requires two basic steps - a high dose oxygen ion implantation (1017 to 1018 cm-3) followed by a high temperature anneal (>1200°C). The result of these processes is to form a buried oxide layer which isolates a top single crystal silicon layer from the underlying substrate. Pairs of threading dislocations can form in the top silicon layer during the high temperature anneal as a result of damage caused during the high dose oxygen implant.

The Surface Structure of Manganese Cation and MnTMPyP Intercalated Potassium Niobate

1998 ◽  
Vol 549 ◽  
Author(s):  
D. H. Lee ◽  
Y. Kim ◽  
O. Sato ◽  
A. Fujishima ◽  
K. Hashimoto
Keyword(s):  
Atomic Force Microscopy ◽  
Cation Exchange ◽  
Surface Structure ◽  
Potassium Niobate ◽  
Oxide Reduction ◽  
Metallic Oxide ◽  
Preliminary Step ◽  
Force Microscopy ◽  
Atomic Force ◽  
Manganese Cation

AbstractK4Nb6O173H2O has a cation exchange ability in K+ ion existing in the interlayer and a property of photocatalyst host. As a preliminary step in the preparation of this catalyst, the cation exchange plays an important role. In this study, we prepared potassium niobate intercalated with Wn2+ and Mn(III)TMPyP7+ (Mn(III)5,10,15,20-tetra(4-pyridyl)-porphyrin) ions and observed the evidence of cation exchange in the interlayer by means of atomic force microscopy. AFM images showed that the Mn2+ ion and MnTMPy7+ cations regularly occupied the potassium sites. This indicates that the metallic oxide reduction center was formed in the interlayer by the cation exchanged species prior to redox treatment and not on the surface of the potassium niobate.

4H-SiC DMOSFETs Processed Using Graphite Capped Implant Activation Anneal

2006 ◽  
Vol 527-529 ◽  
pp. 1265-1268 ◽  
Author(s):  
Jeffery B. Fedison ◽  
Chris S. Cowen ◽  
Jerome L. Garrett ◽  
E.T. Downey ◽  
James W. Kretchmer ◽  
...  
Keyword(s):  
Atomic Force Microscopy ◽  
High Temperature ◽  
Room Temperature ◽  
Gate Oxide ◽  
Surface Roughening ◽  
Force Microscopy ◽  
Atomic Force ◽  
N Source ◽  
High Temperature Anneal ◽  
Blocking Voltage

Results of a 1200V 4H-SiC vertical DMOSFET based on ion implanted n+ source and pwell regions are reported. The implanted regions are activated by way of a high temperature anneal (1675°C for 30 min) during which the SiC surface is protected by a layer of graphite. Atomic force microscopy shows the graphite to effectively prevent surface roughening that otherwise occurs when no capping layer is used. MOSFETs are demonstrated using the graphite capped anneal process with a gate oxide grown in N2O and show specific on-resistance of 64 mW×cm2, blocking voltage of up to 1600V and leakage current of 0.5–3 ´10-6 A/cm2 at 1200V. The effective nchannel mobility was found to be 1.5 cm2/V×s at room temperature and increases as temperature increases (2.8 cm2/V×s at 200°C).

The Effect of Miscut Angle and Miscut Direction of Vicinal (001) SrTiO3 Substrates on The Domain Structure of Epitaxial SrRuO3 Thin Films

1997 ◽  
Vol 474 ◽  
Author(s):  
Q. Gan ◽  
R. A. Rao ◽  
C.B Eom
Keyword(s):  
Thin Films ◽  
Domain Structure ◽  
Epitaxial Thin Films ◽  
X Ray Diffraction ◽  
Orthorhombic Unit Cell ◽  
Metallic Oxide ◽  
Force Microscopy ◽  
Atomic Force ◽  
Step Flow Growth ◽  
Miscut Angle

ABSTRACTWe have grown epitaxial thin films of isotropie metallic oxide SrRuC>3 on both exact and vicinal (001) SrTiO3 substrates with miscut angle (α) up to 5.0° and miscut direction (β) up to 37° away from the in-plane [010] axis. The effects of both α and β on the epitaxial growth and domain structure of epitaxial SrRuC>3 thin films were studied by x-ray diffraction and atomic force microscopy (AFM). On vicinal SrTiO3 substrates with a large miscut angle (α = 1.7°, 2.0°, 4.1°, and 5.0°) and miscut direction close to the [010] axis, single crystal epitaxial (110)° SrRuO3 thin films were obtained. [The superscript o refers to the Miller indices based on the orthorhombic unit cell.] Decreasing the substrate miscut angle or aligning the miscut direction close to the [110] axis (β = 45°) resulted in an increase of 90° domains in the plane. The films grown on vicinal substrates displayed a significant improvement in crystalline quality and in-plane epitaxial alignment as compared to the films grown on exact (001) SrTiO3 substrates. AFM revealed that as the miscut angle increased the growth mechanism changed from two dimensional nucleation to step flow growth.

scholarly journals Electrodeposited WS2 monolayers on patterned graphene

2D Materials ◽  
2021 ◽  
Author(s):  
Yasir Jamal Noori ◽  
Shibin Thomas ◽  
Sami Ramadan ◽  
Victoria Greenacre ◽  
Nema Mohamed Abdelazim ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Scale Production ◽  
X Ray ◽  
2D Material ◽  
Force Microscopy ◽  
Atomic Force ◽  
Transmission Electron ◽  
Single Source Precursor ◽  
Highly Uniform ◽  
Microfabrication Techniques

Abstract The development of scalable techniques to make 2D material heterostructures is a major obstacle that needs to be overcome before these materials can be implemented in device technologies. Electrodeposition is an industrially compatible deposition technique that offers unique advantages in scaling 2D heterostructures. In this work, we demonstrate the electrodeposition of atomic layers of WS2 over graphene electrodes using a single source precursor. Using conventional microfabrication techniques, graphene was patterned to create micro-electrodes where WS2 was site-selectively deposited to form 2D heterostructures. We used various characterization techniques, including atomic force microscopy, transmission electron microscopy, Raman spectroscopy and x-ray photoelectron spectroscopy to show that our electrodeposited WS2 layers are highly uniform and can be grown over graphene at a controllable deposition rate. This technique to selectively deposit TMDCs over microfabricated graphene electrodes paves the way towards wafer-scale production of 2D material heterostructures for nanodevice applications.

Cryogenic atomic force microscopy

1991 ◽  
Vol 49 ◽  
pp. 54-55
Author(s):  
K. A. Fisher ◽  
M. G. L. Gustafsson ◽  
M. B. Shattuck ◽  
J. Clarke
Keyword(s):  
Room Temperature ◽  
Rapid Freezing ◽  
Cryogenic Temperatures ◽  
Soft Or ◽  
Electrically Conductive ◽  
Force Microscopy ◽  
Flexible Molecules ◽  
Advantages And Disadvantages ◽  
Atomic Force ◽  
Chemical Perturbation

The atomic force microscope (AFM) is capable of imaging electrically conductive and non-conductive surfaces at atomic resolution. When used to image biological samples, however, lateral resolution is often limited to nanometer levels, due primarily to AFM tip/sample interactions. Several approaches to immobilize and stabilize soft or flexible molecules for AFM have been examined, notably, tethering coating, and freezing. Although each approach has its advantages and disadvantages, rapid freezing techniques have the special advantage of avoiding chemical perturbation, and minimizing physical disruption of the sample. Scanning with an AFM at cryogenic temperatures has the potential to image frozen biomolecules at high resolution. We have constructed a force microscope capable of operating immersed in liquid n-pentane and have tested its performance at room temperature with carbon and metal-coated samples, and at 143° K with uncoated ferritin and purple membrane (PM).

AFM study of the dynamics of α-alumina surface faceting during high-temperature processing

1995 ◽  
Vol 53 ◽  
pp. 334-335 ◽  
Author(s):  
Michael W. Bench ◽  
Jason R. Heffelfinger ◽  
C. Barry Carter
Keyword(s):  
High Temperature ◽  
Thin Foil ◽  
Sem Analysis ◽  
Conductive Coatings ◽  
Force Microscopy ◽  
Minimal Sample ◽  
Atomic Force ◽  
Formation And Evolution ◽  
High Temperature Processing ◽  
Nominal Surface

To gain a better understanding of the surface faceting that occurs in α-alumina during high temperature processing, atomic force microscopy (AFM) studies have been performed to follow the formation and evolution of the facets. AFM was chosen because it allows for analysis of topographical details down to the atomic level with minimal sample preparation. This is in contrast to SEM analysis, which typically requires the application of conductive coatings that can alter the surface between subsequent heat treatments. Similar experiments have been performed in the TEM; however, due to thin foil and hole edge effects the results may not be representative of the behavior of bulk surfaces.The AFM studies were performed on a Digital Instruments Nanoscope III using microfabricated Si3N4 cantilevers. All images were recorded in air with a nominal applied force of 10-15 nN. The alumina samples were prepared from pre-polished single crystals with (0001), , and nominal surface orientations.

Scanning tunneling microscopy and atomic force microscopy: New tools for biology

1989 ◽  
Vol 47 ◽  
pp. 778-779
Author(s):  
CE Bracker ◽  
P. K. Hansma
Keyword(s):  
Physical Property ◽  
Scanning Probe ◽  
Scanning Tunneling ◽  
Small Scale ◽  
Tunneling Microscopy ◽  
Force Microscopy ◽  
New Family ◽  
Small Probe ◽  
Atomic Force ◽  
Transmission Electron

A new family of scanning probe microscopes has emerged that is opening new horizons for investigating the fine structure of matter. The earliest and best known of these instruments is the scanning tunneling microscope (STM). First published in 1982, the STM earned the 1986 Nobel Prize in Physics for two of its inventors, G. Binnig and H. Rohrer. They shared the prize with E. Ruska for his work that had led to the development of the transmission electron microscope half a century earlier. It seems appropriate that the award embodied this particular blend of the old and the new because it demonstrated to the world a long overdue respect for the enormous contributions electron microscopy has made to the understanding of matter, and at the same time it signalled the dawn of a new age in microscopy. What we are seeing is a revolution in microscopy and a redefinition of the concept of a microscope.Several kinds of scanning probe microscopes now exist, and the number is increasing. What they share in common is a small probe that is scanned over the surface of a specimen and measures a physical property on a very small scale, at or near the surface. Scanning probes can measure temperature, magnetic fields, tunneling currents, voltage, force, and ion currents, among others.

Morphology and development of flow-pattern defect with extended nonagitated Secco etching

1994 ◽  
Vol 52 ◽  
pp. 868-869
Author(s):  
Y. Pan
Keyword(s):  
Flow Pattern ◽  
Silicon Crystal ◽  
Gate Oxide ◽  
Crystal Growth Rate ◽  
Etch Depth ◽  
Force Microscopy ◽  
Etch Pit ◽  
Float Zone ◽  
Atomic Force ◽  
Multiple Step

The D defect, which causes the degradation of gate oxide integrities (GOI), can be revealed by Secco etching as flow pattern defect (FPD) in both float zone (FZ) and Czochralski (Cz) silicon crystal or as crystal originated particles (COP) by a multiple-step SC-1 cleaning process. By decreasing the crystal growth rate or high temperature annealing, the FPD density can be reduced, while the D defectsize increased. During the etching, the FPD surface density and etch pit size (FPD #1) increased withthe etch depth, while the wedge shaped contours do not change their positions and curvatures (FIG.l).In this paper, with atomic force microscopy (AFM), a simple model for FPD morphology by non-crystallographic preferential etching, such as Secco etching, was established.One sample wafer (FPD #2) was Secco etched with surface removed by 4 μm (FIG.2). The cross section view shows the FPD has a circular saucer pit and the wedge contours are actually the side surfaces of a terrace structure with very small slopes. Note that the scale in z direction is purposely enhanced in the AFM images. The pit dimensions are listed in TABLE 1.

Sign in / Sign up

Export Citation Format

Share Document