Resistor array with position dependent heat dissipation

• US 20020015550A1
• Filed: 09/14/2001
• Published: 02/07/2002
• Est. Priority Date: 01/28/2000
• Status: Active Grant

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Ghozeil, Adam L., Schulte, Donald W.
• Granted Patent: US 6,549,690 B2
• Time in Patent Office: Days
• US Class Current: 385/16
• CPC Class Codes: B41J 2/14129 Layer structure
• CPC Class Codes: G02B 26/004 based on a displacement or a deformation of a fluid
• CPC Class Codes: G02B 6/3538 based on displacement or deformation of a liquid controlling the intensity of light by displacement or deformation of a fluid in general G02B26/004; fluid-filled lens of variable focal length G02B3/14
• CPC Class Codes: G02B 6/3546 NxM switch, i.e. a regular array of switches elements of matrix type constellation
• CPC Class Codes: G02B 6/3576 Temperature or heat actuation thermal forces controlling reflecting elements in general G02B26/0866; thermo-optic devices G02F1/0147

Abstract

A thermally actuated fluidic optical switching circuit that includes a heater substructure having heater resistors and thermally conductive regions associated with the heater resistors and configured to tailor the thermal characteristics of the heater substructure.

Claims

1. An optical switching circuit comprising:

a thin film substructure;

a plurality of heater resistors formed in said thin film substructure;

a plurality of thermally conductive regions respectively associated with said heater resistors and dielectrically separated from said heater resistors, each of said thermally conductive regions being located proximately to an associated one of said heater resistors for dissipating heat from said associated heater resistor, wherein said thermally conductive regions have respective areas that are selected so as to tailor respective heat dissipation capacities of associated ones of said heater resistors; and

a waveguide substrate adjacent to said thin film substructure having a plurality of fluidic optical switching elements that are actuated by thermal energy from said heater resistors.

2. The optical switching circuit of claim 1 wherein said heater resistors comprise planar heater resistors, and wherein said thermally conductive regions comprise planar thermally conductive regions.

3. The optical switching circuit of claim 2 wherein said planar thermally conductive regions comprise planar metal regions.

4. The optical switching circuit of claim 3 wherein said planar heater resistors are separated from said planar metal regions by silicon dioxide.

5. The optical switching circuit of claim 4 wherein said thin film substructure includes a silicon substrate.

6. The optical switching circuit of claim 1 wherein said thin film substructure includes a silicon substrate, and wherein said thermally conductive regions comprise metal regions.

7. The optical switching circuit of claim 6 wherein said metal regions are contacted to said silicon substrate.

8. The optical switching circuit of claim 7 further including metal vias for contacting said metal regions to said silicon substrate.

9. The optical switching circuit of claim 7 wherein said metal regions comprise metal contact slabs.

10. The optical switching circuit of claim 1 wherein said areas of said thermally conducting regions vary depending on locations of respective thermally conductive regions in said thin film substructure.

11. The optical switching circuit of claim 10 herein thermally conductive regions in a middle portion of said thin film substructure have respective areas that are greater than areas of thermally conductive regions near edges of said thin film substructure.

12. The optical switching circuit of claim 10 herein thermally conductive regions in a middle portion of said thin film substructure have respective areas that are smaller than areas of thermally conductive regions near edges of said thin film substructure.

14. The heater resistor array of claim 13 wherein said said areas of said metal regions vary depending on location in said thin film substructure.

15. The heater resistor array of claim 13 wherein said thin film substructure includes a silicon substrate.

16. The heater resistor array of claim 15 wherein said metal regions are contacted to said silicon substrate.

17. The heater resistor array of claim 16 further including metal vias for contacting said metal regions to said silicon substrate.

18. The heater resistor array of claim 16 wherein said metal regions comprise metal contact slabs disposed on said silicon substrate.

13. A heater resistor array comprising:

a thin film substructure;

a plurality of thin film heater resistors formed in said thin film substructure; and

a plurality of metal regions respectively associated with said heater resistors and dielectrically separated from said heater resistors, each of said metal regions being located proximately to an associated one of said heater resistors for dissipating heat from said associated heater resistor, wherein said metal regions have respective areas that are selected so as to tailor a heat dissipation characteristic of said thin film substructure.