High-resolution energy distributions of ions, accelerated by the sheath at the powered electrode of a low-pressure 13.56-MHz gas discharge, have been measured. The observed spectra are compared to existing models. Excellent agreement between measured and calculated spectra is obtained. Detailed information on rf sheath behavior is derived from the observed energy profiles and from the measured total ion current densities towards the electrode surface. Analogous to the case of dc discharges, a decrease of sheath thickness is observed when a homogeneous variable magnetic field (0≤B≤315 G) is applied. However, the product of magnetic-field strength B and sheath thickness d is found to be independent of sheath voltage. This leads to the conclusion that in rf discharges, sheath contraction under influence of a magnetic field proceeds by a different mechanism than in dc discharges. It is suggested that the value of the product Bd is determined by the (virtually constant) temperature of the plasma electrons, rather than by the energy of secondary electrons that have been liberated from the electrode surface by ion bombardment. The decrease of sheath thickness d with magnetic-field strength B leads to a changing capacitive-voltage division of the applied generator voltage over the discharge. When the magnetic-field strength is sufficiently high, this may result in a sign reversal of the electrode self-bias voltage.

Ion energy measurements have been performed with an electrostatic parallel plate energy analyzer at the powered electrode of a 13.56–MHz rf discharge. Considerable splitting of the ion energy distributions is observed due to rf oscillations. Plasma potential, sheath thickness, and total ion current are derived from the observed energy profiles. Low-pressure operation of the plasma at several mTorr permits a collisionless sheath approximation and gives rise to well-defined energy spectra.

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A review is presented describing the development of TiN-CVD from the classical, high temperature T i C l m 2 process, towards low temperature MOCVD processes. This development is presented from a chemical point of view. In addition to low pressure (LPCVD) and atmospheric pressure (APCVD) thermal processing, also plasma enhanced (PECVD) techniques are described. In the past few years production facilities for good quality TiN layers for wear resistant applications have come on the market. Production facilities for IC-technology applications of CVD-TiN are on the edge of breaking through. For both applications deposition temperatures have been reduced to 500-600% Research developments, have shown even lower deposition temperatures possible for TiN and Ti(C,N) layers. # Metal organic compounds are defined as chemicals containing metal nitrogen or metal oxygen bonds (e.g. Ti(NMep)4), where organometallic compounds have metal carbon bonds (e.g. CpTiC7H7)