Beryllium oxide pedestals
AssigneeMaterion Corporation
InventorsLarry T. SMITH, Fritz C. GRENSING, Zan ASLETT, Robert E. KUSNER, Jeffrey R. CAMPBELL, Aaron B. SAYER, Kyung H. CHUNG, Gordon V. LU
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Abstract
A base plate containing a having a top and a bottom and comprising a beryllium oxide composition containing at least 95 wt % beryllium oxide and optionally fluorine/fluoride ion. The base plate demonstrates a clamping pressure of at least 133 kPa at a temperature of at least 600° C. and a bulk resistivity greater than 1×105 ohm-m at 800° C.
Claims20
A base plate having a top and a bottom and comprising a beryllium oxide composition, containing at least 95 wt % beryllium oxide and optionally fluorine/fluoride ion;
- wherein the base plate demonstrates a clamping pressure of at least 133 kPa at a temperature of at least 600° C. and a bulk resistivity greater than 1×105 ohm-m at 800° C.
A pedestal assembly comprising:
- a shaft containing a first beryllium oxide composition containing beryllium oxide and fluorine/fluoride ion;
- and
- a base plate containing a second beryllium oxide composition containing at least 95 wt % beryllium oxide;
- wherein the base plate demonstrates a clamping pressure of at least 133 kPa at a temperature of at least 600° C. and a bulk resistivity greater than 1×105 ohm-m at 800° C.
A shaft for a pedestal assembly comprising a beryllium oxide composition containing beryllium oxide and from 10 ppb to 800 ppm fluorine/fluoride ion;
- wherein the beryllium oxide composition has average grain boundaries greater than 0.1 micron or an amorphous grain structure and an average grain size less than 100 microns.
A process for making a base plate, the process comprising the steps of:
- providing a first BeO powder and a third BeO powder;
- forming a second powder from the first and third powders;
- forming a first (bottom) region from the first powder;
- forming a second (middle) region from the second powder;
- forming a third (top) region from the third powder to form a base plate precursor, wherein the second region is disposed between the first and third regions;
- and
- firing the base plate precursor to form the base plate.
Dependencies are inferred from the claim text.