VARIABLE HANDLE WAFER RESISTIVITY FOR SILICON-ON-INSULATOR DEVICES

• US 20170287855A1
• Filed: 03/31/2017
• Published: 10/05/2017
• Est. Priority Date: 03/31/2016
• Status: Abandoned Application

• Current Assignee: Skyworks Solutions Incorporated
• Original Assignee: Skyworks Solutions Incorporated
• Inventors: MASON, Jerod F., WHITEFIELD, David Scott, WANG, Hailing, FUH, Hanching
• Application Number:
  US15/476,252
• Publication Number:
  US 20170287855A1
• Time in Patent Office: Days
• CPC Class Codes: H01L 21/8221 Three dimensional integrated circuits stacked in different levels
• CPC Class Codes: H01L 21/84 the substrate being other than a semiconductor body, e.g. being an insulating body
• CPC Class Codes: H01L 23/538 the interconnection structure between a plurality of semiconductor chips being formed on, or in, insulating substrates H05K takes precedence; manufacture or treatment H01L21/4846 ; mountings per se H01L23/12; materials H01L23/49866
• CPC Class Codes: H01L 23/66 High-frequency adaptations
• CPC Class Codes: H01L 27/0688 Integrated circuits having a three-dimensional layout
• CPC Class Codes: H01L 27/1203 the substrate comprising an insulating body on a semiconductor body, e.g. SOI three-dimensional layout H01L27/0688
• CPC Class Codes: H01L 29/0649 Dielectric regions, e.g. SiO2 regions, air gaps

Abstract

Variable handle wafer resistivity for silicon-on-insulator devices. In some embodiments, a radio-frequency device can include a silicon-on-insulator substrate having an insulator layer and a handle wafer. The radio-frequency device can further include a plurality of field-effect transistors implemented over the insulator layer to cover a corresponding portion of the handle wafer having a non-uniform distribution of resistivity values.

Claims

1. A radio-frequency device comprising:

a silicon-on-insulator substrate including an insulator layer and a handle wafer; and

a plurality of field-effect transistors implemented over the insulator layer to cover a corresponding portion of the handle wafer having a non-uniform distribution of resistivity values.

2. The radio-frequency device of claim 1 wherein the non-uniform distribution of the resistivity values is selected to adjust a radio-frequency performance of some or all of the plurality of transistors.

3. The radio-frequency device of claim 2 wherein the insulator layer includes a buried oxide layer.

4. The radio-frequency device of claim 2 wherein the plurality of transistors are implemented in a stack configuration and arranged in series along a length direction between an input node and an output node.

5. The radio-frequency device of claim 4 wherein the non-uniform distribution is a function of the length direction.

6. The radio-frequency device of claim 5 wherein the non-uniform distribution includes a maximum resistivity value associated with the first transistor adjacent the input node.

7. The radio-frequency device of claim 6 wherein the non-uniform distribution further includes a generally decreasing resistivity values such that the last transistor from the input node has a minimum resistivity value.

8. The radio-frequency device of claim 6 wherein the non-uniform distribution further includes a minimum resistivity value at a transistor that is between the first and last transistors from the input node.

9. The radio-frequency device of claim 2 wherein the plurality of transistors are implemented in a switch having a plurality of stacks, each stack having some of the plurality of transistors.

10. The radio-frequency device of claim 9 wherein the non-uniform distribution includes different resistivity values among the plurality of stacks.

11. The radio-frequency device of claim 1 wherein the plurality of transistors are implemented over the insulator layer having a non-uniform distribution of average thickness values.

12. The radio-frequency device of claim 11 wherein the non-uniform distribution of the average thickness of the insulator layer is selected to adjust radio-frequency performance of some or all of the transistors.

13. A method for fabricating a radio-frequency device, the method comprising:

providing or forming a silicon-on-insulator substrate that includes an insulator layer and a handle wafer; and

forming a plurality of field-effect transistors over the insulator layer, such that the transistors cover a corresponding portion of the handle wafer having a non-uniform distribution of resistivity values.

14. The method of claim 13 wherein the insulator layer includes a buried oxide layer.

15. The method of claim 14 wherein the forming of the plurality of transistors includes forming a stack configuration such that the transistors are arranged in series along a length direction between an input node and an output node.

16. The method of claim 15 wherein the non-uniform distribution is a function of the length direction.

17. The method of claim 16 wherein the non-uniform distribution includes a maximum resistivity associated with the first transistor adjacent the input node.

18. The method of claim 17 wherein the non-uniform distribution further includes a generally decreasing resistivity values such that the last transistor from the input node has a minimum resistivity value.

19. The method of claim 17 wherein the non-uniform distribution further includes a minimum resistivity value at a transistor that is between the first and last transistors from the input node.

20. (canceled)

21. (canceled)

22. A radio-frequency module comprising:

a packaging substrate configured to receive a plurality of devices; and

a switching device mounted on the packaging substrate, the switching device including a silicon-on-insulator substrate having an insulator layer and a handle wafer, the switching device further including a plurality of field-effect transistors implemented over the insulator layer to cover a corresponding portion of the handle wafer having a non-uniform distribution of resistivity values.

23. (canceled)

24. (canceled)

25. (canceled)

26. (canceled)

27. (canceled)