A novel apparatus for in situ compression of submicron structures and particles in a high resolution SEM Rev. Sci. Instrum. 83, 095105 (2012) Foucault imaging by using non-dedicated transmission electron microscope Appl. Phys. Lett. 101, 093101 (2012) New Products Rev. Sci. Instrum. 83, 079501 (2012) Towards secondary ion mass spectrometry on the helium ion microscope: An experimental and simulation based feasibility study with He+ and Ne+ bombardment This review encompasses the application of the scanning electron microscope to the study and characterization of semiconductor materials and devices by the Electron Beam Induced Conductivity (EBIC) method. In this technique, the charge carriers generated by the electron beam of the microscope are collected by an electric field within the material and sensed as a current in an external circuit. When employed as the video signal of the SEM, this collected current image reveals inhomogeneities in the electrical properties of the material. The technique has been used to determine carrier lifetime, diffusion length, defect energy levels, and surface recombination velocities. Charge collection images reveal the location of p-n junctions, recombination sites such as dislocations and precipitates, and the presence of doping level inhomogeneities. Both the theoretical foundation and the practical aspects of these effects are discussed in a tutorial fashion in this review. PACS numbers: 07.80. + x, 61.16.Di, 72.20. -i GLOSSARY OF SYMBOLS C = ill II = image contrast. {j = SrlL = recombination velocity -;-diffusion velocity. D, De' Dh = Diffusion coefficient (D) for electrons (De), and for holes (D h ) (cm2/sec). E = electron beam energy (eV). Eeh = carrier pair creation energy (eV). E bg = band-gap energy (eV). ET = carrier trap energy level (eV). S = electric field strength (V Icm). E = dielectric constant. f = energy fraction of the incident electron beam that is reflected from the sample surface. g = carrier pair generation rate (cm -3).I = electric current (amps). Ib = SEM electron beam current (amps). Ig = IbE(1 -f)IEeh = maximum beam generated current (amps). Icc = collected current (short circuit current) (amps). Is = saturation current of a p-n junction (amps). J e , J h = electron (J e ) or hole (J h ) flux (cm-2 sec-I ). k = Boltzmann's constant = 1.38 X 10-23 I/'K. Leo L h = diffusion length for electrons (L e) and holes (L h ) (cm). m = mass (gms). n = equilibrium electron density (cm -3). iln = excess electron density (cm-3 ). NT = carrier trap density (cm-3 ). NB = net ionized impurity density (cm-3 ). p = equilibrium hole density (cm -3). ilp = excess hole density (cm -3). q = electronic charge = 1.6 X 10-19 C. R = recombination rate (sec-I).R e = electron range (cm). p = density (gm/cm 3 ). S = surface recombination velocity (cm/sec). l: = charge collection efficiency. 0', U e , Uh = capture cross section (0') for electrons (u e ) and holes (u h ) (cm 2 ). T = temperature (OK). T, T e , Th = lifetime (T) for electrons (Te) and for holes (T h ) (sec). T...

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The growth of β-SiC films on Si by reaction of a Si single crystal with C2H2 has been studied for the conditions 10−7 ≤PC2H2≤5×10−4 Torr, 800≤T≤1100°C, in both high- and ultrahigh-vacuum chambers. At C2H2 pressures below approximately 10−5 Torr, linear growth kinetics were observed over the temperature range investigated and the reaction probability was determined as 0.02–0.03. In this pressure range growth occurs by the diffusion of Si through porous defects incorporated in the growing film. We have studied in detail the structure of defected films formed under various growth conditions by scanning electron microscopy, scanning transmission electron microscopy, and transmission electron microscopy. We conclude that the occurrence of defects is intrinsic to the mechanism of film growth. The predominant defect type consists of a shallow (∼ 2000 Å) pit in the Si substrate, over which the growing SiC assumes a porous polycrystalline morphology. The number and areal densities of these defects are proportional to the C2H2 partial pressure and the SiC film thickness, respectively. The defects act as sources of Si for reaction, and film growth occurs via diffusion of Si from the substrate through the porous overgrowth to the epitaxial SiC/vacuum interface, where reaction occurs. For C2H2 pressures exceeding approximately 10−5 Torr the porous defects are sealed off at an early stage in the growth and further reaction is virtually arrested due to the extremely small bulk and/or grain boundary diffusivity for Si in SiC over the experimental temperature range. No significant effect on growth rate due to the type of vacuum system used was found.