Abstract: A thin film capacitor for use in semiconductor integrated circuit devices such as analog circuits, rf circuits, and dynamic random access memories (DRAMs), and a method for its fabrication, is disclosed. The capacitor has a dielectric thickness less than about 50 nm, a capacitance density of at least about 15 fF/.mu.m.sup.2, and a breakdown field of at least about 1 MV/cm. The dielectric material is a metal oxide of either titanium, niobium, or tantalum. The metal oxide can also contain silicon or nitrogen. The dielectric material is formed over a first electrode by depositing the metal onto the substrate or onto a first electrode formed on the substrate. The metal is then anodically oxidized to form the dielectric material of the desired thickness. A top electrode is then formed over the dielectric layer. The top electrode is a metal that does not degrade the electrical characteristics (e.g. the leakage current or the breakdown voltage) of the dielectric layer.

Abstract: The present inventors have discovered that fine patterns of metal or insulator can be formed on printed circuit board using conventional lithographic steppers with inverted projection lenses. The inverted projection lenses act as enlargement lenses rather than reducing lenses and exhibit a large depth of focus sufficient to accommodate the deviations of PC board from planarity. The inverted lens reduces the size of the image needed at the mask, permitting multiple mask levels to be combined on a single glass. This reduces the cost of the mask set and permits the use of smaller glass masks having greater accuracy and dimensional stability than the convention mylar masks used for PC board.By inverting the projection lenses on near-obsolete steppers, applicants were able to form metal patterns on PC board of finer dimension than heretofore reported. Inverting a 5.times. ZEISS lens on a GCA 6300A stepper, applicants were able to form vias of less than 25 .mu.