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Experiments and theory are used to investigate the radial distribution of current at the cathode of a cylindrically symmetric, planar magnetron discharge. We have developed a simple model of the distribution of incident ions at the cathode, in the form of an integral equation. Energetic electrons, produced by secondary electron emission when ions strike the cathode, are accelerated into the discharge through a thin sheath. The Hamiltonian motion of the energetic electrons in the magnetic field determines the birthplace of discharge ions, and thus, the distribution of ion current density at the cathode. The radial current distribution has been measured for various magnetic fields using a radially staggered array of sixteen 1-mm-diam current probes imbedded in a 9-in.-diam cathode. In agreement with the model, the current distribution is peaked at the radius at which the magnetic field is tangent to the cathode plate, and the width of the distribution scales as the square root of the energetic electron Larmor radius.

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Photoluminescence emission and exitation spectra of CdIn,S, and ZnIn,S, spinels are recorded. Both materials have two emission bands in the red spectral region a t 1.52 and 1.89 eV for CdIn,S, and a t 1.52 and 1.29 eV for ZnIn,S,. The excitation maxima for these bands are respectively a t photon energies 2.18 and 2.5 eV for CdIn,S, and 2.14 and 2.35 eV for ZnIn,S,. Additionally, for Cdln,S4 two narrow emission lines in the green spectral region a t 2.39 and 2.52 eV are found. The nature of the recombination centres is discussed. The Raman scattering cross section is measured for several Raman lines as a function of the photon energy of the exciting light. The Alg and F1, modes are found to undergo a resonant enhancement while the E, modes exhibited an antiresonance behaviour. The resonance maxima are located close to the values of the photoluminescence excit,ati.on maxima. Photolumineszenz-Emissionsund Anregungsspektren vori CdIn,S,-und ZnIn&SpineHen werden aufgenommen. Beide Materialien zeigen zwei Emissionsbande im roten Spektralbereich bei 1,52 und 1,89 eV im Falle des CdIn,S, und bei 1,29 und 1,52 eV fur ZnIn,S,. Die dazugehorenden Anregungsmaxima befinden sich bei E,, = 2,18 und 2,5 eV fur CdIn,S, urid bei 2,35 und 2,14 eV fiir ZnIn,S,, wobei E, die Photonenenergie des anregenden Lichtes ist. AuIlerdem werden im grunen Spektralbereich zwei schmale Emissionsbanden bei 2,39 und 2,52 eV gefunden. Die Natnr der Rekombinationszentren wird diskutiert. Gemessen wird auch die Abhangigkeit des Streuquerschnittes mehrerer Raman-Linien von E,. A1,-und Fl,-Moden zeigen Resonanzen, uahrend E,-Moden Antiresonanzen aufweisen. Die Resonanzmaxima liegen bei fast den gleichen Photoneneiiergien wie die Maxima der Photolumineszenzanregung.