Crystal-structure-processed mechanical devices and methods and systems for making

• US 20030196590A1
• Filed: 04/23/2002
• Published: 10/23/2003
• Est. Priority Date: 04/23/2002
• Status: Active Grant

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Hartzell, John W.
• Granted Patent: US 7,125,451 B2
• Time in Patent Office: Days
• US Class Current: 117/88
• CPC Class Codes: C30B 1/02 by thermal treatment, e.g. strain annealing C30B1/12 takes precedence
• CPC Class Codes: C30B 29/00 Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape

Abstract

Laser processing of various materials to create mechanical devices whose internal mechanical properties are provided in final useable form by adjustments made in internal crystalline structure.

Claims

1. A method of forming, from a precursor material having selectively and controllably changeable crystalline-structure-related mechanical properties, a mechanical device possessing (a) a predetermined configuration, and therein (b) a set of such mechanical properties, that are desired for the performance by the completed device of a pre-chosen mechanical task, said method comprising

placing a precursor body of such material in a processing zone,

selecting a volumetric region in that body which is suitable (a) for the creation therefrom of the desired, predetermined device configuration and (b) for the establishment therein of the desired set of crystalline-structure-related mechanical properties,

within the processing zone, subjecting the selected region to a controlled changing of the crystalline structure therein, and thus of the related mechanical properties, and

by that process, achieving, in the selected region, the desired set of mechanical properties.

2. The method of claim 1, wherein the precursor material takes the form of one of an amorphous material, nanocrystalline material, a microcrystalline material, a polycrystalline material, and bulk material.

3. The method of claim 1, wherein the precursor material takes the form of one of silicon, germanium, silicon-germanium, various dielectric materials, various piezoelectric materials, copper, aluminum, tantalum and titanium.

4. The method of claim 1, wherein said placing of a precursor body of material in the processing zone involves placing such material on the surface of a supporting substrate, where the substrate is formed from one of glass, quartz, plastic materials, metal foil materials, dielectric materials, and piezoelectric materials.

5. The method of claim 1, wherein the mechanical device produced is a MEMS device.

6. The method of claim 1, wherein the body of material takes the form of a layer having a defined thickness, and said subjecting involves melting and re-crystallizing of zones in that layer through the full depth of the layer at the location of each zone.

7. The method of claim 1, wherein the body of material takes the form of a layer having a defined thickness, and said subjecting involves melting and re-crystallizing of zones in that layer through less than the full depth of the layer at the location of each zone.

8. The method of claim 1, wherein said subjecting is performed in a manner which differentiates and distinguishes different zones in a region, whereby such differentiated and distinguished zones possess, after the subjecting step, different internal properties.

9. The method of claim 1, wherein said subjecting is performed by a controlled energy beam which is directed toward a surface of the material body.

10. The method of claim 9, wherein the controlled energy beam takes the form of a laser beam.

11. The method of claim 10, wherein, during the subjecting step, the location of beam-body impingement moves over the mentioned surface of the body.

12. The method of claim 1, wherein said subjecting is performed by a pair of controlled energy beams which are directed toward opposite surfaces in the material body.

13. The method of claim 12, wherein the controlled energy beams are laser beams.

14. The method of claim 13, wherein, during the subjecting step, the locations of beam-body impingement move over such opposite surfaces in the body.

15. The method of claim 1, wherein the controlled changing of crystalline structure produces an enlargement of internal grain size.

16. A method of making a task-specific mechanical device at least partially out of a chosen material whose local mechanical properties are closely linked to internal crystalline structure, said method comprising

determining an appropriate spatial configuration for the device,

on the basis of said determining, deciding upon the appropriate distribution in such configuration of local mechanical properties needed for the finished device to be capable of performing the intended specific task, and

applying suitable crystalline-structure-modifying processing to a body of the chosen material to achieve therein a processed region which possesses both the predetermined, appropriate, spatial configuration for the device, and a distributed local crystalline-structure arrangement that produces the decided-upon, distributed, local mechanical properties.

17. A mechanical device-building method comprising

selecting a particular mechanical device to build for the purpose of performing a particular task,

in relation to said selecting, determining for the selected device a three-dimensional configuration, and an internal mechanical properties characteristic within that configuration, suited for the selected particular task,

choosing a material for the creation of the device, and

selectively and controllably processing the internal crystalline structure within the chosen material, and within a region in that material matching the determined device configuration, thus to achieve within that region the desired, determined mechanical properties for the selected particular task.

18. A mechanical device for use in and with respect to a pre-chosen mechanical task comprising

a body of material having a three-dimensional, volumetric configuration suited for the pre-chosen task, and

within that material body, a crystalline structure which is the result of controlled, prior-history processing and changing of that structure, and which establishes the appropriate mechanical properties in the body for the performance of the pre-chosen task.

19. An ambient-temperature method for creating, from a precursor material having selectively and controllably changeable crystalline-structure-related mechanical properties, a mechanical device possessing (a) a predetermined configuration, and therein (b) a set of such mechanical properties, that are desired for the performance by the completed device of a pre-chosen mechanical task, said method comprising

placing a precursor body of such material in a processing zone,

selecting a volumetric region in that body which is suitable (a) for the creation therefrom of the desired, predetermined device configuration, and (b) for the establishment therein of the desired set of crystalline-structure-related mechanical properties,

within the processing zone, subjecting the selected region to a controlled changing of the crystalline structure therein, and thus of the related mechanical properties, said subjecting taking place in the context of a local-only material-body temperature rise, and

by that process, achieving, in the selected region, the desired set of mechanical properties.

20. A method of forming, from a precursor material having selectively and controllably changeable crystalline-structure-related mechanical properties, a mechanical device possessing (a) a predetermined configuration, and therein (b) a set of such mechanical properties, that are desired for the performance by the completed device of a pre-chosen mechanical task, said method comprising,

forming a precursor body of such material,

placing that formed, material body in a processing zone,

within that zone, applying processing to the body to establish, within a selected region therein, an internal crystalline condition which is characterized by possession of a set of the desired crystalline-structure-related mechanical properties, and

at some point in time during implementation of the method, creating from the material body the desired, predetermined device configuration, and doing this in a manner whereby, on completion of the method, the desired configuration is substantially defined by material processed in the selected region.

21. A method of making a defined-task, micro-mechanical device within a size range which, at the lower end extends to single-crystal-level devices, said method comprising

choosing for the creation of such a device a material which possesses crystalline-structure-defining mechanical properties,

selecting a target three-dimensional configuration, and a set of mechanical properties, effective to achieve such a device for the defined task, and

processing the crystalline structure of an appropriate three-dimensional quantity of such chosen material to meet the selected target configuration and set of mechanical properties.

22. A system for forming, from a precursor material having selectively and controllably changeable crystalline-structure-related mechanical properties, a mechanical device possessing (a) a predetermined configuration, and therein (b) a set of such mechanical properties, that are desired for the performance by the completed device of a pre-chosen mechanical task said system comprising,

a processing zone adapted to receive a precursor body of such material,

a laser processing source, operable to direct a controlled beam of laser illumination onto such a precursor body placed within said processing zone, and

computer structure operatively connected to all relevant components in the system and operable to produce translated motion of a point of impingement between a beam of laser radiation from said source over a surface of a precursor body of material within the processing zone in a manner which creates, within the precursor body, a changed character of internal crystalline structure that produces desired mechanical properties for an intended mechanical device that is being built, with such crystalline changed structure residing after processing, in a regional volume within the precursor material capable of defining the three-dimensional configuration of the desired mechanical device.