Patents by Inventor Rointan F. Bunshah
Rointan F. Bunshah has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
-
Patent number: 5747118Abstract: A chemical transport process which is enhanced by a plasma formed in a substantially oxygen free hydrogen environment for formation of microcrystalline diamond films at a relatively low deposition temperature and a rate of about 1 .mu.m/hr. The process, performed at 80 to 180 Torr and a current density of about 1 amp/cm.sup.2 of substrate, can be scaled to deposit films on large areas. The invention further comprises doped diamond films produced by the process, said product having a well-faceted microcrystalline structure with x-ray diffraction pattern and Raman spectra indicative of a predominately diamond structure. The doped diamond films can function as n-type and p-type semiconductors.Type: GrantFiled: August 2, 1995Date of Patent: May 5, 1998Assignee: The Regents of the University of CaliforniaInventors: Rointan F. Bunshah, Hans J. Doerr, Shyankay Jou
-
Patent number: 5698328Abstract: Doped and undoped polycrystalline and noncrystalline diamond films produced by plasma enhanced chemical transport emit electrons into a vacuum in response to an applied electrical field. The field required to create emission is less than 20 V/.mu.m for doped polycrystalline films, can be in the range of 5 to 8 volts/.mu.m for undoped nanocrystalline films and may be 3 volts/.mu.m or less for doped nanocrystalline films. These materials exhibit emission properties which are continuous across the whole surface of the film.Type: GrantFiled: April 21, 1995Date of Patent: December 16, 1997Assignee: The Regents of the University of CaliforniaInventors: Rointan F. Bunshah, Shyankay R. Jou, Hans J. Doerr
-
Patent number: 5494558Abstract: A process and system for producing fullerenes by sputtering. A carbon target is sputtered to form a vapor of sputtered carbon atoms. The sputtered carbon atoms are quenched in an atmosphere of inert gas and deposited onto a collection substrate. The resulting carbon soot is extracted to recover fullerenes. The process produces carbon soot which is rich in C.sub.70 and higher fullerenes.Type: GrantFiled: November 29, 1994Date of Patent: February 27, 1996Assignee: The Regents of the University of CaliforniaInventors: Rointan F. Bunshah, Shyankay Jou, Shiva Prakash, Hans J. Doerr
-
Patent number: 5462750Abstract: A biologically active composition made up of core particles having diameters of less than about 1000 nanometers which are coated with a layer which is designed to allow attachment of biologically active proteins, peptides or pharmacological agents to the microparticles. When viral protein is attached to the core particles, the result is a viral decoy which accurately mimics the native virus in both size and structure while being entirely devoid of virulent activity due to the microparticle core. Other antigenic proteins or peptides are attached to provide molecules which are useful in raising antibodies or as a diagnostic tool. Further, pharmacological agents are attached to the microparticles to provide pharmaceutical compositions.Type: GrantFiled: April 8, 1994Date of Patent: October 31, 1995Assignee: The Regents of the University of CaliforniaInventors: Nir Kossovsky, Rointan F. Bunshah
-
Patent number: 5316636Abstract: A process and system for producing fullerenes by electron beam evaporation of a carbon target in a vacuum. A carbon target is evaporated by an electron beam in a vacuum to form a flux of carbon atoms or clusters. The evaporated carbon atoms or clusters are deposited onto collection substrates which are electrically charged and heated or neutral and chilled. The resulting carbon soot is extracted to recover fullerenes. The process produces carbon soot which is rich in C.sub.70 and higher fullerenes.Type: GrantFiled: August 12, 1992Date of Patent: May 31, 1994Assignee: The Regents of the University of CaliforniaInventors: Rointan F. Bunshah, Shyankay Jou, Shiva Prakash, Hans J. Doerr
-
Patent number: 5219577Abstract: A biologically active composition made up of core particles having diameters of less than about 1000 nanometers which are coated with a layer which is designed to allow attachment of biologically active proteins, peptides or pharmacological agents to the microparticles. When viral protein is attached to the core particles, the result is a viral decoy which accurately mimics the native virus in both size and structure while being entirely devoid of virulent activity due to the microparticle core. Other antigenic proteins or peptides are attached to provide molecules which are useful in raising antibodies or as a diagnostic tool. Further, pharmacological agents are attached to the microparticles to provide pharmaceutical compositions.Type: GrantFiled: June 22, 1990Date of Patent: June 15, 1993Assignee: The Regents of the University of CaliforniaInventors: Nir Kossovsky, Rointan F. Bunshah
-
Patent number: 5178882Abstract: A biologically active composition made up of core particles having diameters of less than about 1000 nanometers which are coated with a layer which is designed to allow attachment of biologically active proteins, peptides or pharmacological agents to the microparticles. When viral protein is attached to the core particles, the result is a viral decoy which accurately mimics the native virus in both size and structure while being entirely devoid of virulent activity due to the microparticle core. Other antigenic proteins or peptides are attached to provide molecules which are useful in raising antibodies or as a diagnostic tool. Further, pharmacological agents are attached to the microparticles to provide pharmaceutical compositions. The viral decoys are useful as vaccines for treating animals to elicit an immune response.Type: GrantFiled: April 24, 1991Date of Patent: January 12, 1993Assignee: The Regents of the University of CaliforniaInventors: Nir Kossovsky, Rointan F. Bunshah
-
Patent number: 5055319Abstract: A process for depositing metal oxides by activated reactive evaporation (ARE) wherein deposition rate and film quality is controlled by reference to the relative amounts of metal and metal oxide present on the surface of the target material. The ratio of metal surface area to metal oxide surface area required to obtain high deposition rates is achieved by maintaining a relatively high concentration of oxygen in the reaction zone. This relative ratio of metal surface area to metal oxide surface area on target material provides a continuous indirect measure of film deposition rate and quality during the ARE process.Type: GrantFiled: April 2, 1990Date of Patent: October 8, 1991Assignee: The Regents of the University of CaliforniaInventors: Rointan F. Bunshah, Chandra V. Deshpandey, Hans J. Doerr, Jong S. Yoon
-
Patent number: 5010035Abstract: A semiconductor device wafer base wherein devices may be fabricated in silicon carbide, the base having a compatible substrate and a beta silicon carbide overlay layer epitaxially related to the substrate, the beta silicon carbide layer being unpolytyped, single crystal, uncracked, without twins, and having integrated circuit quality surface morphology. Preferably, the substrate is a single crystal of titanium carbide, which is the same cubic lattice-type as beta silicon carbide with a lattice parameter different from that of beta silicon carbide by less than about 1%. Additionally, the thermal expansion coefficients of beta silicon carbide and titanium carbide are nearly the same, minimizing the creation of thermal stresses during cooling and heating. The beta silicon carbide is useful in fabricating semi-conductor devices for use at much higher temperatures than is silicon, and for use at high power levels, at high frequencies, and in radiation hardened applications.Type: GrantFiled: May 13, 1988Date of Patent: April 23, 1991Assignee: The Regents of the University of CaliforniaInventors: Rointan F. Bunshah, James D. Parsons, Oscar M. Stafsudd
-
Patent number: 4961958Abstract: A process and apparatus that may be used for the production of diamond and doped diamond films at high rates by activated reactive vapor deposition. Carbon is evaporated in a vacuum chamber in the presence of atomic hydrogen containing plasma to form diamond precursors which then deposit on a substrate located within the vacuum chamber. The substrate temperature is maintained at between about 20.degree.-600.degree. C.Type: GrantFiled: June 30, 1989Date of Patent: October 9, 1990Assignee: The Regents of the Univ. of Calif.Inventors: Chandra V. Desphandey, Rointan F. Bunshah, Hans J. Doerr
-
Patent number: 4931158Abstract: An apparatus and process for reactive magnetron sputtering wherein film deposition is controlled by placing a grid located over the primary plasma and an auxiliary plasma adjacent to the substrate. The auxiliary plasma is produced using a positively biased d.c. probe. Control of the deposited film properties is provided by varying the d.c. probe voltage and open area of the wire grid.Type: GrantFiled: August 8, 1989Date of Patent: June 5, 1990Assignee: The Regents of the Univ. of Calif.Inventors: Rointan F. Bunshah, Chandra V. Deshpandey, Aziz A. Karim
-
Patent number: 4816291Abstract: A process and apparatus that may be used for the production of diamond and doped diamond films at high rates by activated reactive vapor deposition. Carbon is evaporated in a vacuum chamber in the presence of atomic hydrogen containing plasma to form diamond precursors which then deposit on a substrate located within the vacuum chamber.Type: GrantFiled: August 19, 1987Date of Patent: March 28, 1989Assignee: The Regents of the University of CaliforniaInventors: Chandra V. Desphandey, Rointan F. Bunshah, Hans J. Doerr
-
Patent number: 4767666Abstract: A semiconductor device wafer base wherein devices may be fabricated in silicon carbide, the base having a compatible substrate and a beta silicon carbide overlay layer epitaxially related to the substrate, the beta silicon carbide layer being unpolytyped, single crystal, uncracked, without twins, and having integrated circuit quality surface morphology. Preferably, the substrate is a single crystal of titanium carbide, which is the same cubic lattice-type as beta silicon carbide with a lattice parameter different from that of beta silicon carbide by less than about 1%. Additionally, the thermal expansion coefficients of beta silicon carbide and titanium carbide are nearly the same, minimizing the creation of thermal stresses during cooling and heating. The beta silicon carbide is useful in fabricating semiconductor devices for use at much higher temperatures than is silicon, and for use at high power levels, at high frequencies, and in radiation hardened applications.Type: GrantFiled: May 23, 1985Date of Patent: August 30, 1988Assignee: The Regents of the University of CaliforniaInventors: Rointan F. Bunshah, James D. Parsons, Oscar M. Stafsudd