Electronic device sealed under vacuum containing a getter and method of operation
View Patent ↗An electronic device that is sealed under vacuum includes a substrate, a transistor formed on the substrate, and a dielectric layer covering at least a portion of the transistor. The electronic device further includes a layer of non-evaporable getter material disposed on a portion of the dielectric layer; and a vacuum device disposed on a portion of the substrate. Electrical power pulses activate the non-evaporable getter material.
1. An electronic device sealed under vacuum, comprising:
a substrate;
a layer of non-evaporable getter material, disposed over a portion of the substrate;
a layer of electrically resistive material disposed between the substrate and the layer of non-evaporable getter material, wherein electrical power pulses are applied to the layer of electrically resistive material, whereby the layer of non-evaporable getter material is activated; and
a vacuum device disposed on a portion of the substrate.
2. The electronic device of claim 1 , further comprising at least one transistor formed on the substrate.
3. The electronic device of claim 1 , further comprising a substrate temperature sensor disposed on the substrate, wherein the substrate temperature sensor monitors a substrate temperature to limit damage when heating the non-evaporable getter material.
4. The electronic device of claim 1 , further comprising a pressure sensing device disposed on the substrate, wherein the pressure sensing device monitors a pressure to determine when to reactivate the non-evaporable getter material.
5. The electronic device of claim 1 , further comprising a pump driver, wherein the pump driver provides electrical power pulses to activate the non-evaporable getter material.
6. The electronic device of claim 5 , wherein the pump driver further comprises a pulse generator for generating electrical power pulses.
7. The electronic device of claim 6 , further comprising a substrate temperature sensor disposed on the substrate and coupled to the pulse generator wherein the substrate temperature sensor monitors a temperature of the substrate to hinder damage when heating the non-evaporable getter material.
8. The electronic device of claim 6 , further comprising a pressure sensor disposed on the substrate and coupled to the pulse generator, wherein the pressure sensor monitors a pressure to determine when to reactivate the non evaporable getter material.
9. The electronic device of claim 6 , wherein the pulse generator generates electrical power pulses of a predetermined pulse width and a predetermined pulse repetition period.
10. The electronic device of claim 9 , further comprising a processing unit coupled to the pulse generator to generate a second pulse width that is less than the predetermined pulse width and to generate a second pulse repetition period that is greater than the predetermined pulse repetition period.
11. The electronic device of claim 10 , further comprising a reference temperature which establishes a predetermined maximum value for a substrate temperature.
12. The electronic device of claim 1 , wherein the layer of non-evaporable getter material further comprises an array of non-evaporable getter material portions disposed on a portion of a dielectric layer.
13. The electronic device of claim 12 , wherein the substrate has a periphery and the array of non-evaporable getter material portions is disposed around the periphery of the substrate.
14. The electronic device of claim 1 , further comprising a dielectric layer disposed over the substrate, wherein the dielectric layer is comprised of a dielectric material selected from the group consisting of silicon oxide, silicon dioxide, silicon carbide, silicon nitride, aluminum oxide and boron nitride.
15. The electronic device of claim 1 , wherein the non-evaporable getter material comprises material selected from the group consisting of molybdenum, titanium, thorium, and zirconium and combinations thereof.
16. The electronic device of claim 1 , wherein the non-evaporable getter material further comprises a 0.1 micron to 1.0 micron thick layer.
17. The electronic device of claim 1 , wherein the non-evaporable getter material further comprises a 1.0 micron to 10 micron thick layer.
18. The electronic device of claim 1 , wherein the non-evaporable getter material is comprised of a metal, selected from the group consisting of Zr—Al alloys, Zr—V alloys, Zr—V—Fe alloys, and combinations thereof.