Electrically conductive diamond-like carbon (DLC) films were deposited by supermagnetron plasma chemical vapor deposition. The deposition was made on Si and glass wafers using mixed isobutane (i-C4H10) and N2 gases. The physical properties of deposited film were measured and analyzed. Fourier transform infrared spectroscopy measurements revealed that the absorption due to N–H, C–N, and C≡N bonds increased with increases in N2 gas concentration. The increase in electrical conductivity could be attributed to C–N and C≡N bond creation in the DLC films. The lowest resistivity, 0.17 Ω cm, was achieved at an N2 concentration of 70%, gas pressure of 50 mTorr, lower electrode temperature of 160 °C, and rf powers of 1 kW/1 kW. The lowest resistivity film was 1750 kg/mm2 hard, harder than glass (1340 kg/mm2). Raman spectroscopy measurements revealed two peak D and G bands, and the D band was more intense than the G band. The optical band gap decreased with increases in the N2 concentration. Hall measurements showed that the carrier was n type and both carrier density and Hall mobility increased with rf powers.

Hydrogenated amorphous carbon nitride (a-CN x :H) films were formed on p-Si wafers set on a lower electrode by pulsed supermagnetron plasma CVD using i-C 4 H 10 and N 2 gases. Lower electrode RF power (LORF) of 13.56 MHz (50-800 W) was modulated by a 2.5-kHz pulse at a duty ratio of 12.5%, and upper electrode RF power (UPRF) of 50-400 W was supplied continuously. The optical band gap decreased with an increase in LORF at each UPRF. The open circuit voltage of Au/a-CN x :H/p-Si photovoltaic cells (a-CN x :H film thickness: 25 nm) was about 200 mV for each cell, and the short circuit current density and energy conversion efficiency increased with LORF for each UPRF. The highest energy conversion efficiency of 0.81% was obtained at UPRF/LORF of 200/800 W.

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The design, construction and operation of a compact, high-efficiency Bragg diffraction spectrometer are described. An accurate method of alignment is presented. The spectrometer has been tested with a lead stearate analysing crystal by measuring carbon K (methane) and argon L x-ray energies produced by direct electron beam excitation. The high efficiency of this apparatus is demonstrated by measuring satellite lines of the neon K spectrum with a RbAP analysing crystal.

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