International Business Machines Corporation

Wei-Kan Chu

James K Howard

James F White

Arup Bhattacharyya

Jacob Riseman

Ingrid E Magdo

Hans S Rupprecht

William A Pliskin

Francis W Wiedman, Iii

Deep dielectric isolation zones in a substrate are achieved by forming trenches using reactive ion etching. A glass having a coefficient of thermal expansion closely matching that of the substrate is deposited onto the trench to entirely or partially fill the trench. Deposition can be by sedimentation, centrifugation or spin-on techniques. The structure is then fired until the glass particles fuse into a continuous glass layer and final smoothing if necessary can be accomplished.

Deep dielectric isolation by fused glass

A transistor structure is provided with an emitter which is formed from non-monocrystalline silicon which is caused to be converted to monocrystalline silicon during the manufacture of the transistor. In the process of manufacturing the present semiconductor structure, a subcollector is formed in a semiconductor substrate. The subcollector dopant out diffuses into a subsequently deposited epitaxial layer. A base region is formed in the epitaxial layer of a conductivity type opposite that of the conductivity type of the subcollector. This results in a PN junction between the base region and the out diffused subcollector impurities forming the collector of the transistor. A layer of non-monocrystalline silicon is deposited on the epitaxial layer. At least a portion of the non-monocrystalline silicon forms a precursor for an emitter region which is contiguous to but vertically displaced from the surface of the base region. The emitter precursor is then bombarded with ions of a conductivity type that is the same as the conductivity type of the subcollector. The ion bombardment is at a dose and energy level sufficient to displace a portion of the Gaussian distribution of the ions across the interface between the non-monocrystalline layer and the epitaxial layer and into the base region. Thereafter, the structure is annealed by suitable means to drive a portion of the ions deeper into the base region and to convert the non-monocrystalline silicon of the emitter precursor into a monocrystalline emitter region.

Method of making emitter regions by implantation through a

A capacitor is formed by placing between two electodes a thin film of amorphous titanate which has been ion implanted with noble gas ions.

Thin film capacitors

A suitable substrate is provided to which is applied a metal electrically conductive film electrode. The substrate and electrically conductive electrode film are then exposed to ion beam implantation of O+ or N+ ions to impregnate the surface of the metal electrode with O+ or N+ ions. Thereafter, the substrate and electrically conductive film having implanted O+ or N+ ions is annealed so as to stabilize the oxide structure which has been implanted into the surface of the electrically conductive film to provide an ultra-thin dielectric film.

Method for manufacture of ultra-thin film capacitor

Thin film structures comprising a layer of aluminum and a material having a tendency to interact with aluminum are separated by an intermediate layer of aluminum having a high aluminum oxide content. The intermediate layer prevents said interaction by acting as a diffusion barrier. Preferred embodiments are directed to silicon semiconductor metallization structures, including Schottky barrier contacts, which comprise a bottom layer of tantalum, or other transition metal, or a metal silicide in contact with a silicon substrate, an intermediate layer of aluminum having a high aluminum oxide content and a top layer of aluminum. The intermediate layer functions as a diffusion barrier between aluminum and the metal, metal silicide or silicon. The preferred embodiments of the invention also includes the process for forming such structures preferably comprising: depositing pure tantalum under high vacuum in evaporation apparatus, substituting aluminum for tantalum in the evaporation apparatus and bleeding-in water, air or oxygen to form the aluminum oxide-rich intermediate aluminum layer and then returning to the high vacuum to deposit pure aluminum. The invention is also applicable to FET or CCD structures where a diffusion barrier for aluminum is required.

Growing community of inventors

Poughkeepsie, NY, United States of America

Wei-Kan Chu