Carbon nitride films ͑CN x ͒ have been deposited by sputtering a graphite target with nitrogen ions. Films were grown both with and without the presence of an assisting focused N 2 ion beam. The sputter beam voltage was varied between 150 and 1500 V and the applied assisting beam voltage from 80 to 500 V. The substrate was held at fixed temperatures between 80 and 673 K. The coatings were characterized with respect to their electrical, optical, and structural properties. The nitrogen content was measured by x-ray photoelectron spectroscopy ͑XPS͒ and a maximum nitrogen concentration of 44 at. % was obtained for a nonassisted sample deposited at 140 K. The chemical structure was investigated by XPS and Fourier transform infrared spectroscopy. Reduction of the substrate temperature in conjunction with low sputter beam voltages ͑Ͻ200 V͒ caused the optical band gap to increase up to 2.2 eV, the sheet conductivity to decrease to less than 10 Ϫ9 ͑⍀ cm͒ Ϫ1 and the density to be reduced to 1.6 g/cm 3 . The increasing transparency is accompanied by structural changes indicating a transition from a predominantly sp 2 bonded amorphous sp 2 /sp 3 C-N network to a more linear polymerlike structure consisting predominantly of doubly and triply bonded C and N atoms. No evidence for the formation of the ␤-C 3 N 4 phase was found.

Ti–B–N layers have been produced by sputter deposition from a BN target onto which small Ti platelets have been positioned. The Ti–B–N composition has been varied and the films studied by Auger electron spectroscopy (AES) and x-ray photoelectron spectroscopy (XPS). Quantified chemical state information from the XPS B 1s and N 1s peaks give a thin film phase composition consistent with that predicted from the bulk phase diagram. A method of film composition quantification by AES is proposed, accounting for the Ti L3M2,3M2,3 and N KL2,3L2,3 peak overlap problem. Ti L3M2,3M4,5 peak shape changes have been examined using factor analysis, showing the presence of phases and phase changes in qualitative agreement with the phase diagram. Correlations of the compositional and mechanical testing data show that films of highest hardness are obtained when a composition of approximately TiBN0.5 is obtained, the phase composition being a combination of TiB2 and TiN.

Dedicated to Prof. W . Müller-Warmuth on the occasion of his 65 th birthday For the determination of x and y of TiN, and TiB^N coatings two Auger methods are presented, one circumventing and the other minimising the difficulties arising from the overlap of the KL23L23 and L3M23M23 peaks of N and Ti, respectively. The first method, developed for TiNx coatings, is based on the L3M23M45 valence band peak of Ti which develops a distinct second peak on nitridation, 3.9 eV below the main peak, labelled the L3M23Hybrid peak. After a simple Shirley background correction, a linear dependence of the L3M23Hybrid/L3M23M45 peak height ratio on the N/Ti ratio was found. This allows the determination of the N content of a TiNx compound. For TiBxNy coatings, a more complex shape of the L3M23M45 peak is obtained due to the presence of more than one phase, rendering this peak unusable for quantification. Therefore the N/Ti ratio is obtained from the L3M23M23/L3M23M4, peak intensity ratio for Ti. To minimise influences of the fine structure and improve the accuracy of the method, the negative peak excursions were artificially broadened. The N/Ti ratio so obtained is used in combination with the B concentration determined from the KL23L23 peak of B to yield the Ti-B-N composition.

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