Macropore formation on p-type Si in the dark has been studied on 6-inch wafers in aqueous HF solution. More than 10 9 pores with a diameter of 2.5 µm and a depth of 100 µm are obtained in a single etch step. These pores can be used as a template for the fabrication of high-density MOS capacitors. If the current density is close to the characteristic peak for the anodic etching of Si in HF solutions, nanowires are obtained. The length of these wires can reach values up to 100 µm, while their width can be as small as 30 nm. This method is a suitable way to the high-volume production of nanowires.

The authors have investigated the potential of using a dispenser cathode in space charge limited regime for employment in an electron beam lithography electron source. The space charge limitation guarantees stable and uniform emission even if there are small work function variations or bumps and depressions on the surface. Employment of a dispenser cathode in the space charge limited regime enables high beam currents and splitting of the electron beam into many sub-beams for parallel multibeam electron lithography. In the reported experiment, the electron beam is split into 194 sub-beams. The reduced brightness, defined as current divided by normalized emittance, was measured at different cathode temperatures and extraction potentials for a cathode ray tube type electron source equipped with an I-type dispenser cathode. In the central 25 sub-beams, reduced brightness values of up to 106Am−2sr−1V−1 were observed. Such a high reduced brightness in combination with a high total emission current (up to 20mA) indicates potential application in electron beam lithography systems. In accord with theory, the experimentally observed reduced brightness is directly proportional to the emission current density. It was found, however, that the brightness drops if the emission current density is increased beyond the level where the emitter leaves the space charge limited regime. Within the space charge regime, increasing reduced brightness as a function of increasing current density is found to be caused by a decreasing virtual source size, while the angular current density remains nearly invariant.