MONOLITHIC NANOSCALE ACTUATION

• US 20070278896A1
• Filed: 06/05/2006
• Published: 12/06/2007
• Est. Priority Date: 06/05/2006
• Status: Active Grant

• Current Assignee: Zyvex Labs, Llc
• Original Assignee: Zyvex Corporation
• Inventors: Sarkar, Niladri
• Granted Patent: US 7,538,470 B2
• Time in Patent Office: Days
• US Class Current: 310/311
• CPC Class Codes: F03G 7/06 using expansion or contraction of bodies due to heating, cooling, moistening, drying or the like using thermal expansion of non-vaporising liquids F01K
• CPC Class Codes: F05B 2250/82 Micromachines
• CPC Class Codes: Y10T 29/42 Piezoelectric device making

Abstract

An apparatus including an actuator configured for controllable deflection, and also including a piezoresistive element integral to the actuator and having first and second piezoresistive portions and a plurality of contacts. One of the plurality of contacts is configured to pass a received feedback signal through the first and second piezoresistive portions. Detection of the actuator deflection is indicated by comparison of the feedback signal as detected via at least one of the plurality of contacts that are interposed by at least one of the first and second piezoresistive portions.

Claims

1. An apparatus, comprising:

an actuator configured for controllable deflection; and

a piezoresistive element integral to the actuator and having first and second piezoresistive portions and a plurality of contacts, wherein one of the plurality of contacts is configured to pass a received feedback signal through the first and second piezoresistive portions, and wherein detection of the actuator deflection is indicated by comparison of the feedback signal as detected via at least one of the plurality of contacts that are interposed by at least one of the first and second piezoresistive portions.

2. The apparatus of claim 1 further comprising:

a piezoresistive layer comprising a plurality of piezoresistive gate feature portions and the piezoresistive element;

an interconnect structure comprising a plurality of conductive layers each having a first thermal expansion coefficient and a plurality of dielectric layers each having a second thermal expansion coefficient; and

a plurality of transistor devices interconnected by the interconnect structure and each including one of the plurality of piezoresistive gate feature portions;

wherein

the actuator includes portions of the pluralities of conductive and dielectric layers and is configured for temperature-driven positioning by deflection based on a difference between the first and second thermal expansion coefficients.

3. The apparatus of claim 2 wherein the piezoresistive element is one of a plurality of piezoresistive elements included in the piezoresistive layer, and wherein the actuator is one of a plurality of temperature-driven actuators each comprising one of the plurality of piezoresistive elements and portions of the pluralities of conductive and dielectric layers

4. The apparatus of claim 2 wherein the plurality of conductive layers comprises at least one metallic layer and the piezoresistive layer comprises at least one polysilicon layer.

5. The apparatus of claim 2 wherein the piezoresistive layer has a piezoresistivity of at least about 1% and a resistance ranging between about 100 Ω

and about 10 kΩ

.

6. The apparatus of claim 1 the actuator is a first element configured for first temperature-driven deflection to position an object in a first degree-of-freedom, the apparatus further comprising a second element configured for second temperature-driven deflection to position the object in a second degree-of-freedom, wherein the first and second elements are directionally decoupled.

7. The apparatus of claim 1 wherein the actuator is a first element configured for first temperature-driven deflection to position an object in a first degree-of-freedom, the apparatus further comprising a second element configured for second temperature-driven deflection to position the object in a second degree-of-freedom, wherein the first and second elements are further configured to compensate for thermal coupling resulting from either of the first and second temperature-driven deflection.

8. The apparatus of claim 1 wherein the actuator is one of at least two actuators, the apparatus includes a nanopositioner having an end effector and the at least two actuators, the at least two actuators are collectively configured to position the end effector with sub-micron precision in each of at least two degrees-of-freedom, and at least one dedicated electrical path extends through or along the first and second actuators to the end effector, wherein the at least one dedicated electrical path is electrically isolated from other electrically conductive portions of the first and second actuators.

9. The apparatus of claim 1 wherein the actuator is a first actuator, the apparatus further comprising a nanopositioner that includes:

an anchored portion;

an end effector;

the first actuator interposing the anchored portion and the end effector and controllably positionable in a first degree-of-freedom (DOF);

a second actuator interposing the first actuator and the end effector and controllably positionable in a second DOF, wherein the first and second actuators are collectively configured to cooperate to position the end effector with sub-micron precision in each of the first DOF and the second DOF; and

at least one dedicated electrical path extending between the anchored portion and the end effector via the first and second actuators, the at least one dedicated electrical path being electrically isolated from other electrically conductive portions of the first and second actuators.

10. The apparatus of claim 1 wherein:

the actuator is one of a plurality of actuators;

the apparatus further comprises an anchor and an end effector;

the plurality of actuators are mechanically coupled in series or in parallel between the anchor and the end effector;

each of the plurality of actuators are individually configured to position the end effector with sub-micron precision in each of a corresponding one of a plurality of degrees-of-freedom; and

the plurality of actuators are collectively configured to cooperate to exert a force with the end effector, the force having a magnitude greater than zero and less than about 50 μ

N.

11. The apparatus of claim 1 wherein:

the actuator is one of a plurality of actuators;

the apparatus further comprises an electrically controllable positioner configured for installation within a chamber of an electron microscope;

the positioner includes an anchor and an end effector;

the plurality of actuators are mechanically coupled in series or in parallel between the anchor and the end effector and are collectively configured to cooperate to position the end effector with sub-micron precision in each of a plurality of degrees of freedom each corresponding to one of the plurality of actuators; and

the apparatus further comprises a link bundle including no more than ten links over which all power and control signals are received by the actuators from external to the chamber.

12. The apparatus of claim 11 wherein each of the plurality of actuators is configured to position the end effector with sub-micron precision in an exclusive one of the plurality of degrees of freedom.

13. The apparatus of claim 11 further comprising at least one of a proportional-integral-derivative controller, an analog-to-digital converter, a pre-amplifier gain stage, and glue logic apparatus coupled between the link bundle and one of the plurality of actuators.

14. The apparatus of claim 11 wherein the link bundle includes no more than five links over which all power and control signals are received from external to the chamber.

15. The apparatus of claim 11 wherein the link bundle includes no more than three links over which all power and control signals are received from external to the chamber.

16. The apparatus of claim 11 wherein the controller and the plurality of actuators are integrally formed.

17. A method, comprising:

establishing a sub-atmospheric environment within an electron microscope chamber; and

processing an end effector of a positioner installed within the chamber by operating the positioner to transition the end effector towards an end effector processor installed within the chamber, wherein the positioner includes a plurality of actuators mechanically coupled together and each individually configured to position the end effector with sub-micron precision in each of a corresponding one of a plurality of degrees-of-freedom.

18. The method of claim 17 wherein the end effector is monolithic relative to at least one of a plurality of layers from which the actuators are formed.

19. A method of manufacturing an apparatus having at least one feature dimension that is less than about 1000 microns, the method comprising:

forming a patterned piezoresistive layer over a substrate including a piezoresistive feedback portion of an actuator and a plurality of piezoresistive gate elements each corresponding to one of a plurality of transistor devices;

forming a temperature-dependent deflector portion of the actuator by forming a first portion of pluralities of dielectric and conductive layers over the piezoresistive feedback portion of the actuator; and

forming a plurality of conductive members interconnecting the plurality of transistor devices by forming second portions of the dielectric and conductive layers over the plurality of transistor devices.

20. The method of claim 19 wherein the piezoresistive feedback portion includes first and second piezoresistive portions, the method further comprising forming a plurality of contacts, wherein one of the plurality of contacts is configured to pass a received feedback signal through the first and second piezoresistive portions, and wherein detection of the actuator deflection is indicated by comparison of the feedback signal as detected via at least one of the plurality of contacts that are interposed by at least one of the first and second piezoresistive portions.