Abstract: Magnetic confinement of electrons in a plasma reactor is effected using electro-magnetic coils and other magnets which generate respective magnetic fields which are mutually opposed and substantially orthogonal on their common axis to the major plane of a wafer being processed, instead of being aligned and parallel to the major plane as in prior magnetically enhanced plasma reactors. The respective magnetic fields combine to yield a net magnetic field which is nearly parallel to the wafer away from the magnetic axis so that electrons are confined in the usual manner. In addition, a magnetic mirror provides confinement near the magnetic axis. The E.times.B cross product defines a circumferential drift velocity urging electrons about a closed path about the magnetic axis.

Abstract: A method for pretreatment of a photoresist layer adhered to a semiconductor wafer prior to charged particle beam processing. The method includes bombarding the photoresist layer with ions which are electrically inactive with respect to the wafer. Suitable ions include ions of the noble gases. The pretreatment method causes rapid photoresist outgassing and carbonization without altering the electrical properties of the wafer. Outgassing during subsequent processing is thereby reduced. The pretreatment method is particularly applicable to ion implantation wherein dose measurement errors resulting from photoresist outgassing are reduced. The pretreatment method is performed at high current to minimize the effect on system throughput.

Abstract: For enhanced heat conductive transfer from a semiconductor wafer during ion implantation, the wafer is clamped to a platen having a contour f(r,.theta.) computed to establish uniform contact pressure over said wafer for a number, n, of discrete clamping locii distributed along the periphery of the wafer. The available area of the wafer is thus maximized.

Abstract: A unitary electromagnet having two gaps is provided for the double deflection scanning of a charged particle beam. The unitary electromagnet is configured to permit traverse by said beam through the gaps in a plane defined by the gaps. The depth of the gaps is large as compared to the length to accommodate the scan of the beam. The mode of scanning is determined by the waveform used to energize the windings of the electromagnet and includes axial sweep scanning, off center scanning and split scanning.