International Business Machines Corporation

Stephen Scott Furkay

Jeffrey Bowman Johnson

Douglas Duane Coolbaugh

Robert J Gauthier, Jr

Robert Mark Rassel

Jeffrey Scott Brown

David Charles Sheridan

Chung H Lam

Steven H Voldman

James Albert Slinkman

Hon-Sum Philip Wong

Minh H Tong

Dale Warner Martin

Xiaowei Tian

Mohamed Youssef Hammad

David V Horak

Hendrick Hamann

Method of fabricating a varactor that includes providing a semiconductor substrate, doping a lower region of the semiconductor substrate with a first dopant at a first energy level, doping a middle region of the semiconductor substrate with a second dopant at a second energy level lower than the first energy level, and doping an upper region of the semiconductor substrate with a third dopant at a third energy level lower than the second energy level.

Method for forming hyper-abrupt junction varactors

A semiconductor structure comprising a hyperabrupt junction varactor with a compensated cathode contact as well as a method of fabricating the same are disclosed. The method includes a single implant mask which is used in forming the subcollector/cathode, collector/well and hyperabrupt junction.

One mask hyperabrupt junction varactor using a compensated cathode contact

A method and device providing a HA junction varactor which may be fabricated with a reduced variation in C-V tuning curve from one varactor to the next. The process produces a varactor with an active region formed substantially by doping an Si substrate with various dopants at various energy levels. Accordingly, unit-to-unit device variation is reduced because etching, growing, and deposition processes to make the active portion of the varactor are reduced or eliminated. The resulting HA junction has a more uniform thickness, and a more uniform doping profile.

Structure and method for hyper-abrupt junction varactors

Structure and method of hyper-abrupt junction varactors

A storage cell that may be a memory cell, and integrated circuit (IC) chip including an array of the memory cells and a method of forming the IC. Each storage cell is formed between a top an bottom electrode. Each cell includes a phase change layer that may be a chalcogenide and in particular a germanium (Ge), antimony (Sb), tellurium (Te) or GST layer. The cell also includes a stylus with the apex of the stylus contacting the GST layer. The apex may penetrate the GST layer

Field emission phase change diode memory

The present invention includes a method for forming a phase change material memory device and the phase change memory device produced therefrom. Specifically, the phase change memory device includes a semiconductor structure including a substrate having a first doped region flanked by a set of second doped regions; a phase change material positioned on the first doped region; and a conductor positioned on the phase change material, wherein when the phase change material is a first phase the semiconductor structure operates as a bipolar junction transistor, and when the phase change material is a second phase the semiconductor structure operates as a field effect transistor.

Phase change memory cell on silicon-on insulator substrate

A varactor diode having a first electrode comprising a well region of a first conductivity type in a substrate, a second electrode comprising a first plurality of diffusion regions of a second conductivity type abutting isolation regions disposed in said well region, and a second plurality of diffusion regions of said first conductivity type extending laterally from portions of said first plurality of diffusion regions not adjacent said isolation regions and having a dopant concentration greater than that of said first plurality of diffusion regions. The varactor has a tunability of at least approximately 3.5 in a range of applied voltage between approximately 0V to 3V, an approximately linear change in capacitive value in a range of applied voltage between approximately 0V to 2V, and a Q of at least approximately 100 at a circuit operating frequency of approximately 2 GHz.

High performance varactor diodes

A FET with reduced reverse short channel effects is described, as well as a method to make said FET. Germanium is implanted throughout a semiconductor substrate at an intensity and dose such that a peak ion concentration is created below the source and drain of the FET. The germanium can be implanted prior to gate and source and drain formation, and reduces the reverse short channel effect normally seen in FETs. The short channel effect normally occurring in FETs is not negatively impacted by the germanium implant.

Reduction of reverse short channel effects by implantation of neutral dopants

Reduction of reverse short channel effects by deep implantation of neutral dopants

A semiconductor device and method of fabrication for such device in which a P- epitaxial layer is positioned above a P++ substrate. A P++ buried layer implant is positioned within the device between the P++ substrate and the P- epitaxial layer. A connecting p+ implant is placed within the epitaxial layer above the buried p+ blanket layer implant. In one exemplary embodiment, the device includes a shallow P-well with the P+ connecting implant in a position within the epitaxial layer connecting the shallow P-well and the buried P+ blanket implant layer.

Semiconductor device fabrication method and apparatus using connecting

Semiconductor device fabrication method using connecting implants

Disclosed is a method of improved grid generation for semiconductor device simulation. In particular, the invention includes a simple method for locating critical interfaces (e.g., oxide-silicon interfaces) and then utilizing the information to generate finer mesh elements near those boundaries where device behavior is most critical. The method of identifying critical interfaces includes the steps of examining the boundary data for each material region in the device, and then generating normal lines between adjacent boundaries to identify 'thin' regions, which are generally associated with the critical interfaces. Once this occurs, a recursive subdivision algorithm may be utilized to generate a grid whose element dimensions are dependent upon their proximity to identified critical regions.

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South Burlington, VT, United States of America

Stephen Scott Furkay