Large-area electronics

For printed electronics, large areas have to be printed with electronic functionality. This requires homogeneous layers of electronically active materials, of a defined thickness and with defined surface and interfaces. These layers have to be printed and patterned with a high resolution, to obtain as much... 

The flexible large area screen with photostimulable phosphor called the imaging plate, which temporarily stores the image induced by the ionizing radiation, e g. by X-rays, electrons or other charged particles ... 

The history of EM (for an overview see table Bl.17,1) can be interpreted as the development of two concepts the electron beam either illuminates a large area of tire sample ( flood-beam illumination , as in the typical transmission electron microscope (TEM) imaging using a spread-out beam) or just one point, i.e. focused to the smallest spot possible, which is then scaimed across the sample (scaiming transmission electron microscopy (STEM) or scaiming electron microscopy (SEM)). In both situations the electron beam is considered as a matter wave interacting with the sample and microscopy simply studies the interaction of the scattered electrons. 

An XPS spectrometer schematic is shown in Figure 7. The X-ray source is usually an Al- or Mg-coated anode struck by electrons from a high voltage (10—15 kV) Alka or Mgka radiation lines produced at energies of 1486.6 eV and 1256.6 eV, with line widths of about 1 eV. The X rays flood a large area (-I cm ). The beam s spot size can be improved to about lOO-jim diameter by focusing the electron beam... 

Both XRF and EPMA are used for elemental analysis of thin films. XRF uses a nonfocusing X-ray source, while EPMA uses a focusing electron beam to generate fluorescent X rays. XRF gives information over a large area, up to cm in diameter, while EPMA samples small spots, (om in size. An important use of EPMA is in point-to-point analysis of elemental distribution. Microanalysis on a sub- lm scale can be done with electron microscopes. The penetration depth for an X-ray beam is normally in the 10-(om range, while it is around 1 (om for an electron beam. There is, therefore, also a difference in the depth of material analyzed by XRF and EPMA... 

Quantitative Analysis. In its basic form, AES provides compositional information on a relatively large area ( 1 mm2 ) of surface, using a broad-focussed electron beam probe. Sufficient signal may be obtained in this way with a low incident electron flux, thus avoiding potential electron-induced modifications of the surface. 

Shimizu KT, Fabbri JD, Jelincic JJ, Melosh NA (2006) Soft deposition of large-area metal contacts for molecular electronics. Adv Mater 18 1499—1504... 

Akkerman HB, Blom PWM, de Leeuw DM, de Boer B (2006) Towards molecular electronics with large-area molecular junctions. Nature 441 69-72... 

Preiner MJ, Melosh NA (2008) Creating large area molecular electronic junctions using atomic layer deposition. Appl Phys Lett 92 213301... 

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