Method for making a solder joint

Information

  • Patent Grant
  • 8925793
  • Patent Number
    8,925,793
  • Date Filed
    Tuesday, October 30, 2012
    12 years ago
  • Date Issued
    Tuesday, January 6, 2015
    9 years ago
Abstract
A method of bonding an electrical component to a substrate includes applying solder paste on to a substrate. Solder preform has an aperture is formed therethrough and is then urged into contact with the solder paste, such that solder paste is urged through the aperture. An electrical component is then urged into contact with the solder preform and into contact with the solder paste that has been urged through the aperture, thereby bonding the electrical component, the solder preform, and the substrate together to define a reflow subassembly.
Description
BACKGROUND OF THE INVENTION

Various embodiments of a method of forming a solder joint are described herein. In particular, the embodiments described herein relate to a method of forming a solder joint with improved process control and superior solder joint reliability.


Solder is frequently used in the production of electronic components to join integrated circuit modules or chip carriers to circuit cards or circuit boards. For example, solder may be used to connect conductive metal pins from a module to the conductive circuit lines of a circuit card. It is known to apply solder to the components in the form of a solder preform or a solder paste. A solder preform is a solid composition of solder or braze material fabricated to the shape and dimensions required to contact the desired locations of each of the components to be joined. The preform is placed in proper position and subsequently heated to cause the solder to flow, or “reflow,” and physically join the components.


Solder paste is a composition of a solder powder in one or more liquid solvents or binders. The paste is screened on to the components, dried, and heated to reflow the solder and join the two components. For both preforms and pastes, a liquid flux is typically used to deoxidize the metal surfaces of the components to cause them to accept the solder.


The use of a conventional liquid flux results in flux residues left behind on the surface of the components after soldering. For example, a common flux such as waterwhite rosin leaves a metal salt residue abietate formed when the abietic acid in the rosin reacts with oxides on the metal surfaces of the components. Where the residue contacts the metal surfaces of the components, it will cause detrimental galvanic corrosion upon the passage of electrical current in normal use. Thus, the residue must be removed from the components after soldering and before electrical use.


Another problem associated with that of soldering electronic components is that of precision. To assure that proper electrical connections, electrical components must often be joined according to tight dimensional tolerances. Solder preforms are inherently difficult to use in such applications because precision is limited by the accuracy by which the preform is placed upon the components, and fixtures must be used to hold the electrical components, circuit modules, or chip carriers to circuit cards or circuit boards during the solder reflow process.


Micro electro mechanical systems (MEMS) are a class of systems that are physically small, having some features or clearances with sizes in the micrometer range or smaller (i.e., smaller than about 10 microns). These systems have both electrical and mechanical components. The term “micro machining” is commonly understood to mean the production of three-dimensional structures and moving parts of MEMS devices. MEMS originally used modified integrated circuit (e.g., computer chip) fabrication techniques (such as chemical etching) and materials (such as silicon semiconductor material) to micro machine these very small mechanical devices. Today there are many more micro machining techniques and materials available. The term “MEMS device” as may be used in this application is defined as a device that includes a micro machined component having some features or clearances with sizes in the micrometer range, or smaller (i.e., smaller than about 10 microns). It should be noted that if components other than the micro machined component are included in the MEMS device, these other components may be micro machined components or standard sized (i.e., larger) components. Similarly, the term “microvalve” as may be used in this application means a valve having features or clearances with sizes in the micrometer range, or smaller (i.e., smaller than about 10 microns) and thus by definition is at least partially formed by micro machining. The term “microvalve device” as may be used herein means a device that includes a microvalve, and that may include other components. It should be noted that if components other than a microvalve are included in the microvalve device, these other components may be micro machined components or standard sized (i.e., larger) components. The term “MEMS package” as used herein should be understood to mean a device, which includes a micromachined component and may include other components that may be micromachined components or standard sized components. A “MEMS fluidic package” should be understood to be a MEMS package including a fluid passageway. A “MEMS electrofluidic package” as used herein should be understood to be a MEMS package including a fluid passageway and an electrically active component that may be a micromachined component. A “MEMS package platform” as used herein should be understood to be an interface component or assembly of components upon which a MEMS device may be mounted and by means of which the MEMS device can be interfaced with an external system.


Many MEMS devices may be made of multiple layers (or substrates) of material, which may be micromachined to form components of the MEMS device prior to assembly of the multiple layers into a completed MEMS device. For example, such a MEMS device may be manufactured using suitable MEMS fabrication techniques, such as the fabrication techniques disclosed in U.S. Pat. No. 6,761,420, the disclosures of which are incorporated herein by reference; U.S. Pat. No. 7,367,359, the disclosures of which are incorporated herein by reference; Klassen, E. H. et al. (1995). “Silicon Fusion Bonding and Deep Reactive Ion Etching: A New Technology for Microstructures,” Proc. Transducers 95 Stockholm Sweden, pp. 556-559, the disclosures of which are incorporated herein by reference; and Petersen, K. E. et al. (Jun. 1991). “Surface Micromachined Structures Fabricated with Silicon Fusion Bonding”, “Proceedings, Transducers” 91, pp. 397-399, the disclosures of which are incorporated herein by reference.


Flux and/or flux residue may undesirably coat the internal moving components of the MEMS device when a MEMS device is attached to a substrate using known soldering processes.


The above notwithstanding, there remains a need in the art for an improved method of forming a solder joint.


SUMMARY OF THE INVENTION

The present application describes various embodiments of a method of forming a solder joint. In one embodiment, a method of soldering an electrical component to a substrate includes dispensing solder paste onto a substrate. Solder preform is then urged into contact with the solder paste. An aperture is formed through the solder preform, such that solder paste is urged through the aperture. An electrical component is then urged into contact with the solder preform and into contact with the solder paste that has been urged through the aperture, thereby bonding the electrical component, the solder preform, and the substrate together.


Other advantages of the method of forming a solder joint will become apparent to those skilled in the art from the following detailed description, when read in light of the accompanying drawings.





BRIEF DESCRIPTION OF THE DRAWINGS


FIG. 1 is an exploded schematic elevational view of a reflow subassembly manufactured according to the method of the invention.



FIG. 2 is an enlarged plan view of a first embodiment of the solder preform illustrated in FIG. 1.



FIG. 3 is an enlarged plan view of a second embodiment of the solder preform.



FIG. 4 is a plan view of the assembled reflow subassembly illustrated in FIG. 1.





DETAILED DESCRIPTION OF THE INVENTION

The present invention will now be described with occasional reference to the specific embodiments of the invention. This invention may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.


Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for describing particular embodiments only and is not intended to be limiting of the invention. As used in the description of the invention and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise.


Unless otherwise indicated, all numbers expressing quantities of ingredients, properties such as molecular weight, reaction conditions, and so forth as used in the specification and claims are to be understood as being modified in all instances by the term “about.” Accordingly, unless otherwise indicated, the numerical properties set forth in the specification and claims are approximations that may vary depending on the desired properties sought to be obtained in embodiments of the present invention. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical values, however, inherently contain certain errors necessarily resulting from error found in their respective measurements.


Referring now to the Figures, there is shown in FIG. 1 a schematic illustration of a method of soldering an electrical component to a substrate according to the invention is shown at 10. In the illustrated embodiment, an electrical component 12 is bonded to a substrate 14, such as for use in automotive or air conditioning applications. In the illustrated embodiment, the electrical component 12 is a micro-electrical-mechanical system (MEMS) sensor. Alternatively, the electrical component may be any desired electrical component, such as a microvalve, a MEMs device, a MEMS package, a MEMS fluidic package, a semiconductor component, a circuit module, and a chip carrier.


In the illustrated embodiment, the substrate 14 is formed from metal, such as brass. Alternatively, the substrate 14 may be formed from any other desired metal or non-metal.


In a first step of the method 10, solder paste 16 is applied to a first or upper surface 14U of the substrate 14. In the illustrated embodiment, the solder paste 16 is applied using a screen printing process. The screen printing process is used to apply uniformly thick deposits of solder paste 16 at one or more discrete locations on the substrate 14. Such screen printing of the solder paste 16 provides precise control of the volume and pattern of the solder paste 16 at the desired discrete locations.


The solder paste 16 may be any desired solder paste. As used herein, “solder paste” is defined as a homogenous mixture of solder alloy powder and a flux system. The solder paste 16 should have characteristics that provide good printing and dispensing, and exhibit good reflow characteristics. Examples of solder pastes that have been found to be suitable in some applications to practice the method described herein include tin-lead and indium-lead solder pastes, such as manufactured by Indium Corporation, which has an office in Clinton, New York.


In a second step of the method 10, an engineered solder preform 18 is deposited on the screen printed layer of solder paste 16. As used herein,_a “solder preform” is defined as a solid composition of solder or braze material fabricated to the shape and dimensions required to contact the desired locations of each of the components to be joined. Solder preforms contain precise and predetermined quantities of an alloy or pure metal, such as lead-tin or lead-indium.


As best shown in FIG. 2, a first embodiment of the solder preform 18 is substantially square and includes at least one aperture 20 and at least one notch 22. Alternatively, the solder preform 18 may have any other desired shape corresponding to the desired shape of the solder joint between the electrical component 12 and the substrate 14. The illustrated solder preform 18 includes four oval apertures 20 and one notch 22 on each side of the solder preform 18. Alternatively, any desired number of apertures 20 and/or notches 22 may be formed in the solder preform 18, and the apertures 20 and/or notches 22 may have any desired shape or combination of shapes.


Referring now to FIG. 3, a second embodiment of the solder preform 24 is substantially square and includes at least one aperture 20 and at least one notch 26. In the illustrated embodiment of the solder preform 24, the notches 26 are formed in the corners of the solder preform 24. It will be understood that one or more notches 26 may be formed at any desired location along the peripheral edges of the solder preform 24.


The solder preform 18, 24 is then urged into contact with the solder paste 16 such that a limited amount of solder paste 16 is urged through the apertures 20 and notches 22. As used herein, the phrase “limited amount of solder paste” is defined as a quantity of solder paste approximating the minimum amount of solder paste needed to develop the mechanical properties required to hold components, such as the electrical component 12 and the substrate 14 in the spatial relationship into which they are assembled when subjected to ordinary handling during a manufacturing process that includes a subsequent soldering operation and/or a subsequent reflow operation. As described herein, the limited amount of solder paste 16 that is urged through the apertures 20 and notches 22 is sufficient to fill and at least partially spill over the edges of the apertures 20 and notches 22.


In a third step of the method 10, the electrical component 12 is urged into contact with the solder preform 18 and into contact with the solder paste 16 that has been urged through the apertures 20 and notches 22. The tacky solder paste 16 preliminarily bonds the electrical component 12, the solder preform 18, and the substrate 14 together to define a reflow subassembly 28, as shown in FIGS. 1 and 4, in preparation for a subsequent reflow operation (not shown). As used herein, the phrase “preliminarily bond” is defined as a permanent or semi-permanent bond strong enough to allow the reflow subassembly to be handled, moved to a source of heat, and subsequently heated, such as in a reflow operation, without the use of a fixture.


In a fourth step (not shown) of the method 10, the reflow subassembly 28 is moved to a source of heat where the electrical component 12, the solder preform 18, and the substrate 14 of the reflow subassembly 28 are bonded together in a reflow operation.


Advantageously, because the tacky solder paste 16 bonds the electrical component 12, the solder preform 18, and the substrate 14 together prior to a reflow operation, no fixtures are required to hold the reflow subassembly 28 together.


Further, flux within the limited amount of solder paste 16 that has been urged through the apertures 20 and notches 22 provides sufficient, but not excessive, flux to a first or upper surface 18U of the solder preform 18. Such improved delivery of flux (within the solder paste 16) to the interface of the solder preform 18 and the electrical component 12, provides increased strength of the solder joint relative to other known methods of solder fortification.


Additionally, unlike known methods of solder fortification, additional adhesive material may not be required between the solder preform 18 and the electrical component 12.


It will be understood that the embodiments of the inventive method described herein is useful for components with internal moving components that may be exposed to the solder paste during assembly. The inventive method limits contamination of such internal moving components with flux from the solder paste, which may cause sticking of the moving components. The embodiments of the inventive method are also useful for components without internal moving components, such as microprocessor chips and memory chips since this method can be easily automated for manufacturing highly reliable solder joints.


The principle and mode of operation of the method of forming a solder joint have been described in its preferred embodiment. However, it should be noted that the method of forming a solder joint described herein may be practiced otherwise than as specifically illustrated and described without departing from its scope.

Claims
  • 1. A method of bonding a component to a substrate comprising: applying solder paste on to a substrate;urging a solder preform made of solder or braze material into contact with the solder paste, the solder preform having a channel in the form of at least one of an aperture and a notch formed therethrough, such that solder paste is urged through the channel in an amount sufficient to fill and at least partially spill over edges of the channel; andurging a component into contact with the solder preform and into contact with the solder paste that has been urged through the channel, thereby bonding the component, the solder preform, and the substrate together to define a reflow subassembly.
  • 2. The method according to claim 1, wherein the component is a MEMS device.
  • 3. The method according to claim 1, wherein the solder paste includes flux.
  • 4. The method according to claim 1, wherein the substrate is metal.
  • 5. The method according to claim 1, further including the step of moving the reflow subassembly to a source of heat.
  • 6. The method according to claim 5, further including the step of applying heat from the source of heat to the reflow subassembly, thereby reflowing the solder preform to bond the component and the substrate together, and defining a solder joint.
  • 7. The method according to claim 1, wherein the bond between the component, the solder preform, and the substrate is strong enough to allow the reflow subassembly to be moved to a subsequent process step without an assembly fixture.
  • 8. The method according to claim 1, wherein the solder paste is applied on to the substrate using a screen printing process.
  • 9. A method of bonding a MEMS device to a substrate comprising: applying solder paste on to a substrate;urging a solder preform made of solder or braze material into contact with the solder paste, the solder preform having an aperture formed therethrough, such that solder paste is urged through the aperture in an amount sufficient to fill and at least partially spill over edges of the aperture; andurging a MEMS device into contact with the solder preform and the solder paste that has been urged through the aperture, thereby bonding the MEMS device, the solder preform, and the substrate together to define a reflow subassembly.
  • 10. The method according to claim 9, wherein the solder paste includes flux.
  • 11. The method according to claim 10, wherein the limited amount of solder paste that is urged through the aperture provides flux between the solder preform and the MEMS device via the solder paste.
  • 12. The method according to claim 9, wherein the substrate is formed from metal.
  • 13. The method according to claim 9, further including the step of moving the reflow subassembly to a source of heat.
  • 14. The method according to claim 13, further including the step of applying heat from the source of heat to the reflow subassembly, thereby reflowing the solder preform to bond the MEMS device and the substrate together, and defining a solder joint.
  • 15. The method according to claim 9, wherein the bond between the MEMS device, the solder preform, and the substrate is strong enough to allow the reflow subassembly to be moved to a subsequent process step without an assembly fixture.
  • 16. A method of bonding a component to a substrate comprising: a) applying a quantity of a fluxing agent on to a substrate;b) providing a solder preform made of solder or braze material having at least one channel in the form of at least one of an aperture and a notch formed therethrough,c) urging the solder preform into the fluxing agent, such that a portion of the fluxing agent is displaced through the channel formed in the solder preform in an amount sufficient to fill and at least partially spill over edges of the channel; andd) urging a component into contact with some of the fluxing agent that has been urged through the channel.
  • 17. The method of claim 16 where the fluxing agent is a solder paste containing solder and flux.
  • 18. The method of claim 16 wherein the component has a flat surface, and wherein the flat surface of the component is urged into contact with the portion of the fluxing agent displaced through the channel, such that the portion of the fluxing agent disposed in an interface of the solder preform and the component provides a quantity of flux quantity required to achieve a good solder joint and not a quantity of flux excessive to that required to achieve a good solder joint.
US Referenced Citations (207)
Number Name Date Kind
668202 Nethery Feb 1901 A
886045 Ehrlich et al. Apr 1908 A
1886205 Lyford Nov 1932 A
1926031 Boynton Sep 1933 A
2412205 Cook Dec 1946 A
2504055 Thomas Apr 1950 A
2651325 Lusignan Sep 1953 A
2840107 Campbell Jun 1958 A
2875779 Campbell Mar 1959 A
3031747 Green May 1962 A
3540218 Finn Nov 1970 A
3729807 Fujiwara May 1973 A
3747628 Holster et al. Jul 1973 A
3860949 Stoeckert et al. Jan 1975 A
4005454 Froloff et al. Jan 1977 A
4019388 Hall, II et al. Apr 1977 A
4023725 Ivett et al. May 1977 A
4100236 Gordon et al. Jul 1978 A
4152540 Duncan et al. May 1979 A
4181249 Peterson et al. Jan 1980 A
4298023 McGinnis Nov 1981 A
4341816 Lauterbach et al. Jul 1982 A
4354527 McMillan Oct 1982 A
4434813 Mon Mar 1984 A
4476893 Schwelm Oct 1984 A
4543875 Imhof Oct 1985 A
4581624 O'Connor Apr 1986 A
4593719 Leonard et al. Jun 1986 A
4628576 Giachino et al. Dec 1986 A
4647013 Giachino et al. Mar 1987 A
4661835 Gademann et al. Apr 1987 A
4687419 Suzuki et al. Aug 1987 A
4752027 Gschwend Jun 1988 A
4772935 Lawler et al. Sep 1988 A
4774760 Seaman et al. Oct 1988 A
4821997 Zdeblick Apr 1989 A
4824073 Zdeblick Apr 1989 A
4826131 Mikkor May 1989 A
4828184 Gardner et al. May 1989 A
4842184 Miller, Jr. Jun 1989 A
4869282 Sittler et al. Sep 1989 A
4938742 Smits Jul 1990 A
4943032 Zdeblick Jul 1990 A
4946350 Suzuki et al. Aug 1990 A
4959581 Dantlgraber Sep 1990 A
4966646 Zdeblick Oct 1990 A
5000009 Clanin Mar 1991 A
5029805 Albarda et al. Jul 1991 A
5037778 Stark et al. Aug 1991 A
5050838 Beatty et al. Sep 1991 A
5054522 Kowanz et al. Oct 1991 A
5058856 Gordon et al. Oct 1991 A
5061914 Busch et al. Oct 1991 A
5064165 Jerman Nov 1991 A
5065978 Albarda et al. Nov 1991 A
5066533 America et al. Nov 1991 A
5069419 Jerman Dec 1991 A
5074629 Zdeblick Dec 1991 A
5082242 Bonne et al. Jan 1992 A
5096643 Kowanz et al. Mar 1992 A
5116457 Jerman May 1992 A
5131729 Wetzel Jul 1992 A
5133379 Jacobsen et al. Jul 1992 A
5142781 Mettner et al. Sep 1992 A
5161774 Engelsdorf et al. Nov 1992 A
5169472 Goebel Dec 1992 A
5176358 Bonne et al. Jan 1993 A
5177579 Jerman Jan 1993 A
5178190 Mettner Jan 1993 A
5179499 MacDonald et al. Jan 1993 A
5180623 Ohnstein Jan 1993 A
5197517 Perera Mar 1993 A
5209118 Jerman May 1993 A
5215244 Buchholz et al. Jun 1993 A
5216273 Doering et al. Jun 1993 A
5217283 Watanabe Jun 1993 A
5222521 Kihlberg Jun 1993 A
5238223 Mettner et al. Aug 1993 A
5242097 Socha Sep 1993 A
5244537 Ohnstein Sep 1993 A
5267589 Watanabe Dec 1993 A
5271431 Mettner et al. Dec 1993 A
5271597 Jerman Dec 1993 A
5309943 Stevenson et al. May 1994 A
5323999 Bonne et al. Jun 1994 A
5325880 Johnson et al. Jul 1994 A
5333831 Barth et al. Aug 1994 A
5336062 Richter Aug 1994 A
5355712 Petersen et al. Oct 1994 A
5368704 Madou et al. Nov 1994 A
5373984 Wentworth Dec 1994 A
5375919 Furuhashi Dec 1994 A
5400824 Gschwendtner et al. Mar 1995 A
5417235 Wise et al. May 1995 A
5445185 Watanabe et al. Aug 1995 A
5458405 Watanabe Oct 1995 A
5543349 Kurtz et al. Aug 1996 A
5553790 Findler et al. Sep 1996 A
5566703 Watanabe et al. Oct 1996 A
5577533 Cook, Jr. Nov 1996 A
5589422 Bhat Dec 1996 A
5611214 Wegeng et al. Mar 1997 A
5785295 Tsai Jul 1998 A
5796169 Dockerty et al. Aug 1998 A
5810325 Carr Sep 1998 A
5820014 Dozier et al. Oct 1998 A
5838351 Weber Nov 1998 A
5848605 Bailey et al. Dec 1998 A
5856705 Ting Jan 1999 A
5873385 Bloom et al. Feb 1999 A
5908098 Gorman et al. Jun 1999 A
5909078 Wood et al. Jun 1999 A
5924622 Davis et al. Jul 1999 A
5926955 Kober Jul 1999 A
5941608 Campau et al. Aug 1999 A
5954079 Barth et al. Sep 1999 A
5955817 Dhuler et al. Sep 1999 A
5970998 Talbot et al. Oct 1999 A
5994816 Dhuler et al. Nov 1999 A
6019437 Barron et al. Feb 2000 A
6023121 Dhuler et al. Feb 2000 A
6038928 Maluf et al. Mar 2000 A
6041650 Swindler et al. Mar 2000 A
6095400 Liu Aug 2000 A
6096149 Hetrick et al. Aug 2000 A
6105737 Weigert et al. Aug 2000 A
6114794 Dhuler et al. Sep 2000 A
6116863 Ahn et al. Sep 2000 A
6123316 Biegelsen et al. Sep 2000 A
6124663 Haake et al. Sep 2000 A
6171972 Mehregany et al. Jan 2001 B1
6182742 Takahashi et al. Feb 2001 B1
6224445 Neukermans et al. May 2001 B1
6255757 Dhuler et al. Jul 2001 B1
6279606 Hunnicutt et al. Aug 2001 B1
6283441 Tian Sep 2001 B1
6318101 Pham et al. Nov 2001 B1
6321549 Reason et al. Nov 2001 B1
6386507 Dhuler et al. May 2002 B2
6390782 Booth et al. May 2002 B1
6408876 Nishimura et al. Jun 2002 B1
6494804 Hunnicutt et al. Dec 2002 B1
6505811 Barron et al. Jan 2003 B1
6520197 Deshmukh et al. Feb 2003 B2
6523560 Williams et al. Feb 2003 B1
6533366 Barron et al. Mar 2003 B1
6540203 Hunnicutt Apr 2003 B1
6581640 Barron Jun 2003 B1
6637722 Hunnicutt Oct 2003 B2
6653124 Freeman Nov 2003 B1
6662581 Hirota et al. Dec 2003 B2
6694998 Hunnicutt Feb 2004 B1
6724718 Shinohara et al. Apr 2004 B1
6755761 Hunnicutt et al. Jun 2004 B2
6761420 Fuller et al. Jul 2004 B2
6786391 Stipp et al. Sep 2004 B2
6845962 Barron et al. Jan 2005 B1
6848610 Liu Feb 2005 B2
6872902 Cohn et al. Mar 2005 B2
6902988 Barge et al. Jun 2005 B2
6958255 Khuri-Yakub et al. Oct 2005 B2
6966329 Liberfarb Nov 2005 B2
7011378 Maluf et al. Mar 2006 B2
7063100 Liberfarb Jun 2006 B2
7210502 Fuller et al. May 2007 B2
7367359 Maluf et al. May 2008 B2
7372074 Milne et al. May 2008 B2
7449413 Achuthan et al. Nov 2008 B1
7452800 Sosnowchik et al. Nov 2008 B2
8061578 Hartnett et al. Nov 2011 B2
8113448 Keating Feb 2012 B2
8113482 Hunnicutt Feb 2012 B2
8156962 Luckevich Apr 2012 B2
20020014106 Srinivasan et al. Feb 2002 A1
20020029814 Unger et al. Mar 2002 A1
20020096421 Cohn et al. Jul 2002 A1
20020100714 Staats Aug 2002 A1
20020168780 Liu et al. Nov 2002 A1
20020174891 Maluf et al. Nov 2002 A1
20030061889 Tadigadapa et al. Apr 2003 A1
20030096081 Lavallee et al. May 2003 A1
20030098612 Maluf et al. May 2003 A1
20030159811 Nurmi Aug 2003 A1
20030206832 Thiebaud et al. Nov 2003 A1
20040115905 Barge et al. Jun 2004 A1
20040219072 Yamakawa et al. Nov 2004 A1
20050121090 Hunnicutt Jun 2005 A1
20050200001 Joshi et al. Sep 2005 A1
20050205136 Freeman Sep 2005 A1
20060017125 Lee et al. Jan 2006 A1
20060067649 Tung et al. Mar 2006 A1
20060218953 Hirota Oct 2006 A1
20070251586 Fuller et al. Nov 2007 A1
20070289941 Davies Dec 2007 A1
20080028779 Song Feb 2008 A1
20080042084 Fuller Feb 2008 A1
20080072977 George et al. Mar 2008 A1
20080229770 Liu Sep 2008 A1
20080271788 Matsuzaki et al. Nov 2008 A1
20090123300 Uibel May 2009 A1
20090186466 Brewer Jul 2009 A1
20100019177 Luckevich Jan 2010 A1
20100038576 Hunnicutt Feb 2010 A1
20100204840 Sun et al. Aug 2010 A1
20100225708 Peng et al. Sep 2010 A1
20110112606 Gatherer et al. May 2011 A1
20120000550 Hunnicutt et al. Jan 2012 A1
Foreign Referenced Citations (40)
Number Date Country
2215526 Oct 1973 DE
2930779 Feb 1980 DE
3401404 Jul 1985 DE
4101575 Jul 1992 DE
4417251 Nov 1995 DE
4422942 Jan 1996 DE
250948 Jan 1988 EP
261972 Mar 1988 EP
1024285 Aug 2000 EP
2238267 May 1991 GB
SHO 39-990 Feb 1964 JP
04-000003 Jan 1992 JP
06-117414 Apr 1994 JP
2001184125 Jul 2001 JP
2003-049933 Feb 2003 JP
SHO 63-148062 Jul 2003 JP
2006-080194 Mar 2006 JP
9916096 Apr 1999 WO
9924783 May 1999 WO
0014415 Mar 2000 WO
0014415 Jul 2000 WO
2005084211 Sep 2005 WO
2005084211 Jan 2006 WO
2006076386 Jul 2006 WO
2008076388 Jun 2008 WO
2008076388 Aug 2008 WO
2008121365 Oct 2008 WO
2008121369 Oct 2008 WO
2010019329 Feb 2010 WO
2010019329 Feb 2010 WO
2010019665 Feb 2010 WO
2010019665 Feb 2010 WO
2010065804 Jun 2010 WO
2010065804 Jun 2010 WO
2011022267 Feb 2011 WO
2011022267 Feb 2011 WO
2011094300 Aug 2011 WO
2011094300 Aug 2011 WO
2011094302 Aug 2011 WO
2011094302 Aug 2011 WO
Non-Patent Literature Citations (49)
Entry
Alpha Exactalloy Solder Performs [online], [retrieved Jan. 5, 2011]. Retrieved from the Internet <URL: http://alpha.cooksonelectronics.com/products/preforms/>.
Asuha, Hikaru Kobayashi et al, “Nitric acid oxidation of Si to form ultrathin silicon dioxide layers with a low leakage current density”, 2003, Journal of Applied Physics, 94, 7328.
Ayon et al., “Etching Characteristics and Profile Control in a Time Multiplexed ICP Etcher,” Proc. Of Solid State Sensor and Actuator Workshop Technical Digest, Hilton Head SC, (Jun. 1998) 41-44.
B.E. Deal and A.S. Grove, “General relationship for the thermal Oxidation of Silicon”, 1965, Journal of Applied Physics, 36, 3770.
Bachmann, Stephan, “Electronic Expansion Valves: Fitters Notes (Part 8)”, Danfoss Fitters Notes, Jul. 2008.
Bartha et al., “Low Temperature Etching of Si in High Density Plasma Using SF6/02,” Microelectronic Engineering, and Actuator Workshop Technical Digest, Hilton Head SC, (Jun. 1998) 41-44.
Biography, Ohio State University Website [online], [retrieved Dec. 31, 2000]. Retrieved from the Internet <URL: http://www.chemistry.ohio-state.edu/resource/pubs/brochure/madou.htm>.
Booth, Steve and Kaina, Rachid, Fluid Handling—Big Gains from Tiny Valve, Appliance Design (Apr. 2008), pp. 46-48.
Changenet et al., “Study on predictive functional control of an expansion valve for controlling the evaporator superheat”, Proc.IMechE vol. 222 Part I, May 28, 2008, pp. 571-582.
Clark, Scott, “Etching Silicon Dioxide with Aqueous Hf Solutions”, Copyright 1998-2000, Bold Technologies Inc., http://www.bold-tech.com/technical/silicon—dioxide.htm.
Controls Overview for Microstaq Silicon Expansion Valve (SEV), Rev. 1, Dec. 2008 [online], [retrieved May 17, 2010]. Retrieved from the Internet <URL: http://www.microstaq.com/pdf/SEV—controls.pdf>.
Copeland, Michael V., Electronic valves promise big energy savings, FORTUNE, Sep. 9, 2008 [online], [retrieved Sep. 9, 2008]. Retrieved from the internet <URL: http://techland.blogs.fortune.cnn.com/2008/09/09/electronic-valves-promise-big-energy-savings>.
Fung et al., “Deep Etching of Silicon Using Plasma” Proc. Of the Workshop on Micromachining and Micropackaging of Transducers, (Nov. 7-8, 1984) pp. 159-164.
Gui, C. et al, “Selective Wafer Bonding by Surface Roughness Control”, Journal of The Electrochemical Society, 148 (4) G225-G228 (2001).
Gui, C. et al., “Fusion bonding of rough surfaces with polishing technique for silicon micromachining”, Microsystem Technologies (1997) 122-128.
Günther, Götz, “Entwicklung eines pneumatischen 3/2-Wege-Mikroventils”, O+ P Olhydraulik Und Pneumatik, Vereinigte Fachverlage, Mainz, DE, vol. 42, No. 6, Jun. 1, 1998, pp. 396-398, XP000831050, ISSN: 0341-2660.
Higginbotham, Stacey, Microstaq's Tiny Valves Mean Big Energy Savings [online], [retrieved Dec. 8, 2008]. Retrieved from the Internet <URL: http//earth2tech.com/2008/09/09/microstaqs-tiny-valves-mean-big-energy savings (posted Sep. 9, 2008)>.
J. Mark Noworolski, et al.,“Process for in-plane and out-of-plane single-crystal-silicon thermal microactuators”, Sensors and Actuators A 55 (1996); pp. 65-69.
Jonsmann et al., “Compliant Electra-thermal Microactuators”, IEEE Technical Digest , Twelfth IEEE International Conference on Micro Electro Mechanical Systems Jan. 17-21, 1999, Orlando, Florida, pp. 588-593, IEEE Catalog Number: 99CH36291C.
K.R. Williams et al., “A Silicon Microvalve For The Proportional Control Of Fluids”, TRANSDUCERS '99, Proc. 10th International Conference on Solid State Sensors and Actuators, held Jun. 7-10, 1999, Sendai, Japan, pp. 18-21.
Keefe, Bob, Texas firm says value-replacing chip can drastically cut energy use, Atlanta Metro News, Sep. 10, 2008 [online], [retrieved Sep. 10, 2008]. Retrieved from the Internet <URL: http://www.ajc.com/search/content/shared/money/stories/2008/09/microstaq10—cox-F9782.html>.
Klaassen et al., “Silicon Fusion Bonding and Deep Reactive Ion Etching; A New Technology for Microstructures,” Proc., Transducers 95 Stockholm Sweden, (1995) 556-559.
Linder et al., “Deep Dry Etching Techniques as a New IC Compatible Tool for Silicon Micromachining,” Proc, Transducers, vol. 91, (Jun. 1991) pp. 524-527.
Luckevich, Mark, MEMS microvlaves: the new valve world, Valve World (May 2007), pp. 79-83.
Madou, Marc, “Fundamentals of Microfabrication”, Boca Raton: CRC Press, 1997, 405-406.
MEMS, Microfluidics and Microsystems Executive Review [online], Posted Apr. 16, 2009. [retrieved May 17, 2010]. Retrieved from the Internet <URL: http:www.memsinvestorjournal.com/2009/04/mems-applications-for-flow-control.html>.
Microstaq Announces High Volume Production of MEMS-Based Silicon Expansion Valve [onlne], [retrieved Jan. 27, 2010]. Retrieved from the Internet <URL: http://www.earthtimes.org/articles/printpressstory.php?news+1138955 (posted Jan. 27, 2010)>.
Microstaq Product Description, Proportional Piloted Silicon Control Valve (CPS-4) [online], Published 2008, [retrieved May 17, 2010]. Retrieved from the Internet <URL: http://www.microstaq.com/products/cps4.html>.
Microstaq Product Description, Proportional Direct Acting Silicon Control Valve (PDA-3) [online], Published 2008, [retrieved May 17, 2010]. Retrieved from the Internet <URL: http://www.microstaq.com/products/pda3.html>.
Microstaq Product Descriptions, SEV, CPS-4, and PDA-3 [online], Published 2009, [retrieved May 17, 2010]. Retrieved from the Internet <URL: http://www.microstaq.com/products/index.html>.
Microstaq Technology Page [online], Published 2008, [retrieved May 17, 2010]. Retrieved from the Internet <URL: http://www.microstaq.com/technology/index.html>.
Petersen et al. “Surfaced Micromachined Structures Fabricated with Silicon Fusion Bonding” Proc., Transducers 91, (Jun. 1992) pp. 397-399.
Press Release, Freescale and Microstaq Join Forces on Smart Superheat Control System for HVAC and Refrigeration Efficiency (posted Jan. 22, 2008) [online], [retrieved May 17, 2010]. Retrieved from the Internet <URL: http://www.microstaq.com/pressReleases/prDetail—04.html>.
Press Release, Microstaq Unveils Revolutionary Silicon Expansion Valve at Demo 2008 [online], [retrieved May 17, 2010]. Retrieved from the Internet <URL: http://www.microstaq.com/pressReleases/prDetail—05.html (posted Sep. 8, 2008)>.
Press Release, Microstaq Mastering Electronic Controls for Fluid-Control Industry (posted May 5, 2005) [online[, [retrieved May 17, 2010]. Retrieved from the Internet <URL: http://www.microstaq.com/pressReleases/prDetail—02.html>.
Press Release, Nanotechnology Partnerships, Connections Spur Innovation for Fluid Control Industries (posted Jun. 9, 2005) [online], [retrieved May 17, 2010]. Retrieved from the Internet <URL: http://www.microstaq.com/pressReleases/prDetail—03.html>.
Product Review, greentechZONE Products for the week of May 18, 2009 [online], [retrieved May 17, 2010]. Retrieved from the Internet <URL: http://www.en-genius.net/site/zones/greentechZONE/product—reviews/grnp—051809>.
SEV Installation Instructions [online], [retrieved May 17, 2010]. Retrieved from the Internet <URL: http://www.microstaq.com/pdf/SEV—Instruction—sheet.pdf>.
Silicon Expansion Valve Information Sheet [online], [retrieved May 17, 2010]. Retrieved from the Internet <URL: http://www.microstaq.com/pdf/SEV—Infosheet—2—0.pdf>.
Silicon Expansion Valve Data Sheet [online], [retrieved May 17, 2010]. Retrieved from the Internet <URL: http://www.microstaq.com/pdf/SEV—Datasheet—1—8.pdf>.
Silicon Expansion Valve (SEV)—For Heating, Cooling, and Refrigeration Applications [online], [retrieved May 17, 2010]. Retrieved from the Internet <URL: http://www.microstaq.com/pdf/SEV—Quicksheet.pdf>.
SMIC Announces Successful Qualification of a MEMS Chip for Microstaq (posted Oct. 26, 2009) [online], [retrieved May 17, 2010]. Retrieved from the Internet <URL: http://www.prnewswire.com/news-releases/smic-announces-successful-qualification-of-a-mems-chip-for-microstaq-65968252.html (posted Oct. 26, 2009)>.
SMIC quals Microstaq MEMS chip for fluid control (posted Oct. 26, 2009) [online], [retrieved May 17, 2010]. Retrieved from the Internet <URL: http://www.electroiq.com/ElectroiQ/en-us/index/display/Nanotech—Article—Tools—Template.articles.small- times.nanotechmems.mems.microfluidics.2009.10.smic-quals—microstaq.html>.
Tiny Silicon Chip Developed by Microstaq Will Revolutionize Car Technology (posted May 19, 2005) [online], [retrieved May 19, 2005]. Retrieved from the Internet <URL: http://www.nsti.org/press/PRshow.html?id=160>.
Turpin, Joanna R., Soft Economy, Energy Prices Spur Interest in Technologies [online], Published Dec. 8, 2008. [retrieved May 18, 2010]. Retrieved from the Internet <URL: http://www.achrnews.com/copyright/BNP—GUID—9-5-2006—A—10000000000000483182>.
Uibel, Jeff, The Miniaturization of Flow Control (Article prepared for the 9th International Symposium on Fluid Control Measurement and Visualization (FLUCOME 2007)), Journal of Visualization (vol. 11, No. 1, 2008), IOS Press.
Yunkin et al., “Highly Anisotropic Selective Reactive Ion Etching of Deep Trenches in Silicon,” Microelectronic Engineering, Elsevier Science B.V., vol. 23, (1994) pp. 373-376.
Zhang, Chunbo et al, “Fabrication of thick silicon dioxide layers for thermal isolation”, 2004, J.Micromech. Microeng. 14 769-774.
Zhixiong Liu et al., “Micromechanism fabrication using silicon fusion bonding”, Robotics and Computer Integrated Manufacturing 17 (2001) 131-137.
Related Publications (1)
Number Date Country
20130175330 A1 Jul 2013 US
Provisional Applications (1)
Number Date Country
61583364 Jan 2012 US