Thomas E Nemecek

20140066287, Mar 6, 2014

Mar 13, 2013

13/798368

Thomas NEMECEK - Tempe AZ, US
Robert TESCH - Phoenix AZ, US

C04B 35/581

501152, 423412, 264650

A sintered aluminum nitride substrate having a thermal conductivity of about 60 W/m-K to about 150 W/m-K, a flexural strength of about 200 MPa to about 325 MPa, a volume resistivity of greater than 10Ohm cm, a density of at least about 95% of theoretical, optionally at least 97%, and a reflectance factor of at least about 60% substantially over the wavelength range of 360 nm to 820 nm. A low temperature process for sintering aluminum nitride includes providing an AlN sintering formulation of AlN powder and a sintering aid of yttria, calcia, and optionally added alumina, forming the AlN sintering formulation into a green body, and sintering the green body at a temperature of about 1675 C. to 1750 C.

60174854, Jan 25, 2000

Mar 28, 1996

8/622994

Rudolph C. Enck - Phoenix AZ
Jonathan H. Harris - Scottsdale AZ
Robert A. Youngman - Paradise Valley AZ
Thomas S. Nemecek - Tempe AZ

Carborundum Corporation - Phoenix AZ

C04B 35582

264618

A controlled dielectric loss, sintered aluminum nitride body having a density of greater than about 95% theoretical, a thermal conductivity of greater than about 100 W/m-K, and a dissipation factor measured at room temperature at about 1 KHz selected from: (a) less than or equal to about 0. 001; and (b) greater than or equal to about 0. 01. A process for producing a controlled dielectric loss, sintered aluminum nitride body, comprising heat treating an aluminum nitride body at sintering temperatures, including providing a heat treatment atmosphere which effects a selected nitrogen vacancy population in the aluminum nitride body at the sintering temperatures, and cooling the aluminum nitride body from sintering temperatures at a controlled rate and in a cooling atmosphere effective to control the selected nitrogen vacancy population.