WO2009154567A1 - Buse d'éjection d'eau à haute pression résistante à l'usure - Google Patents

Buse d'éjection d'eau à haute pression résistante à l'usure Download PDF

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Publication number
WO2009154567A1
WO2009154567A1 PCT/SG2008/000217 SG2008000217W WO2009154567A1 WO 2009154567 A1 WO2009154567 A1 WO 2009154567A1 SG 2008000217 W SG2008000217 W SG 2008000217W WO 2009154567 A1 WO2009154567 A1 WO 2009154567A1
Authority
WO
WIPO (PCT)
Prior art keywords
orifice
water jet
jet nozzle
nozzle
downstream surface
Prior art date
Application number
PCT/SG2008/000217
Other languages
English (en)
Inventor
Wee Soon Tan
K.K. Fong
Arun Palani
C.P. Fang
Original Assignee
Aem Singapore Pte Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Aem Singapore Pte Ltd filed Critical Aem Singapore Pte Ltd
Priority to PCT/SG2008/000217 priority Critical patent/WO2009154567A1/fr
Publication of WO2009154567A1 publication Critical patent/WO2009154567A1/fr

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B08—CLEANING
    • B08B—CLEANING IN GENERAL; PREVENTION OF FOULING IN GENERAL
    • B08B13/00—Accessories or details of general applicability for machines or apparatus for cleaning
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
    • B05B1/00—Nozzles, spray heads or other outlets, with or without auxiliary devices such as valves, heating means
    • B05B1/02—Nozzles, spray heads or other outlets, with or without auxiliary devices such as valves, heating means designed to produce a jet, spray, or other discharge of particular shape or nature, e.g. in single drops, or having an outlet of particular shape
    • B05B1/04—Nozzles, spray heads or other outlets, with or without auxiliary devices such as valves, heating means designed to produce a jet, spray, or other discharge of particular shape or nature, e.g. in single drops, or having an outlet of particular shape in flat form, e.g. fan-like, sheet-like
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
    • B05B15/00—Details of spraying plant or spraying apparatus not otherwise provided for; Accessories
    • B05B15/14—Arrangements for preventing or controlling structural damage to spraying apparatus or its outlets, e.g. for breaking at desired places; Arrangements for handling or replacing damaged parts
    • B05B15/18—Arrangements for preventing or controlling structural damage to spraying apparatus or its outlets, e.g. for breaking at desired places; Arrangements for handling or replacing damaged parts for improving resistance to wear, e.g. inserts or coatings; for indicating wear; for handling or replacing worn parts
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24C—ABRASIVE OR RELATED BLASTING WITH PARTICULATE MATERIAL
    • B24C5/00—Devices or accessories for generating abrasive blasts
    • B24C5/02—Blast guns, e.g. for generating high velocity abrasive fluid jets for cutting materials
    • B24C5/04—Nozzles therefor

Definitions

  • the present invention relates broadly to a water jet nozzle, to a method for fabricating a water jet nozzle, and to a method of de-flashing.
  • a semiconductor package comprises an encapsulated portion 130 with leads 120 and a heat sink 140 disposed at each end of the encapsulated portion 130.
  • unwanted flashes 110 may be present around the encapsulated portion 130 and over the leads 120 of a semiconductor package 100 as seen in Figure 1A.
  • the lead portion 120 of the semiconductor package 100 is plated. However, due to the presence of the unwanted flashes 1 10, the lead portion 120 under these unwanted flashes 110 will not be plated. During the operation, the unwanted flashes 110 may break down and expose the un-plated lead portion 120 to the atmospheric air. This will result in the lead portion 120 to be oxidized by the atmospheric air and become weakened. The weakened lead portion 120 can ultimately lead to product failure.
  • one of the processes to remove the unwanted flashes comprises two steps: electro chemical immersion/chemical immersion followed by high- pressure water jet de-flashing.
  • electro chemical immersion/chemical immersion the semiconductor packages are immersed in a chemical which is carried by a belt apparatus at an appropriate speed to satisfy the 'chemical immersion timing'. Typically, this normal timing varies between 60-90 seconds.
  • the unwanted flashes are softened and are removed by a high-pressure water jet de-flashing by the thrust force of the water jet produced by a high-pressure water jet nozzle.
  • a semiconductor package with the unwanted flashes 110 removed is as illustrated in Figure 1B.
  • electro chemical immersion there is an additional step of supplying an electric current to the semiconductor packages by a rectifier to enhance the softening process.
  • the high-pressure water jet nozzle used to remove the unwanted flashes from semiconductor packages should efficiently convert the pressure energy into kinetic energy i.e. thrust force, and the nozzle should be wear-resistant.
  • a wom-off nozzle can diminish the nozzle performance, thus directly affecting the quality of de-flashing.
  • straight water jet nozzles are also used to remove unwanted flashes.
  • a disadvantage in using straight water jet nozzles is that the length of the water spray and the target area cannot vary. Furthermore, water sprayed by straight water jet nozzles may affect other parts of the semiconductor packages, thus causing unnecessary damage to the product.
  • a water jet nozzle comprising a main body formed from a first material; a downstream surface comprising an orifice; and an upstream surface comprising a chamber extending towards the orifice; wherein at least a circumferential wall defining the orifice is coated with a second material, the second material having a greater hardness compared to the first material.
  • the coating may extend over at least a portion of a wall defining the chamber.
  • the downstream surface may further comprise a V groove and the orifice is formed at a bottom portion of the V groove.
  • the coating may extend over at least a portion of the bottom portion of the V groove adjacent the orifice.
  • the V groove may be formed in a recess formed in the downstream surface.
  • the recess may comprise substantially perpendicular side walls with respect to the downstream surface.
  • the chamber may comprise, in a downstream order, a frusto-conical portion, a cylindrical portion, and a conical portion extending towards the orifice.
  • the orifice may be elliptical.
  • the coating may comprise a diamond coating.
  • the diamond coating may be formed using ionization.
  • a method of fabricating a water jet nozzle comprising providing a main body formed from a first material; forming a downstream surface comprising an orifice; and forming an upstream surface comprising a chamber extending towards the orifice; and coating at least a circumferential wall defining the orifice with a second material, the second material having a greater hardness compared to the first material.
  • the method may further comprise forming the orifice as a substantially horizontally bent ellipse.
  • Parameters of the substantially horizontally bent ellipse may be chosen such that the nozzle exhibits a desired spray angle.
  • Parameters of the substantially horizontally bent ellipse may be chosen such that the nozzle exhibits a desired flow rate at a given water pressure.
  • a method of de-flashing packaged semiconductor devices comprising directing a water jet towards the packaged semiconductor device using a water jet nozzle comprising a main body formed from a first material; a downstream surface comprising an orifice; and an upstream surface comprising a chamber extending towards the orifice; wherein at least a circumferential wall defining the orifice is coated with a second material, the second material having a greater hardness compared to the first material.
  • Figure 1A shows unwanted flashes present around the encapsulated portion and over the leads of a conventional semiconductor package
  • Figure 1 B shows unwanted flashes removed from the encapsulated portion and over the leads of the conventional semiconductor package
  • Figures 2A and 2B are perspective views of a high-pressure nozzle assembly in accordance with an embodiment of the present invention
  • Figures 3A and 3B are perspective views of a nozzle in accordance with an embodiment of the present invention.
  • Figure 4 is another perspective view of the nozzle in accordance with an embodiment of the present invention.
  • Figure 5A and 5B are cross-sectional views of the nozzle in accordance with an embodiment of the present invention.
  • Figure 6A shows an exemplary view of a high-pressure water jet spray in accordance with an embodiment of the present invention
  • Figure 6B illustrates the principle of a water jet spray to achieve water jet spray in accordance with an embodiment of the present invention
  • Figure 7 shows a graph illustrating pressure against flow rate in accordance with an embodiment of the present invention.
  • Figure 8 shows a flow chart illustrating a method of fabricating a water jet nozzle according to an example embodiment.
  • FIG. 2A shows a perspective front view of a high-pressure nozzle assembly 200 in an example embodiment.
  • Figure 2B shows a perspective rear view of the high- pressure nozzle assembly 200 in an example embodiment.
  • the high-pressure nozzle assembly comprises of a mounting cap 210, a nozzle 220 and a base member 230.
  • the mounting cap 210 comprises of a downstream surface 290, a chamfer 240 near a hole 250 along the axis of the mounting cap 210.
  • the mounting cap 210 further comprises a cylindrical surface 280, an internal chamfer 260, a side chamfer 270 and four flat surfaces 255.
  • the internal chamfer 260 is disposed near the edge of the chamfer 240, while the side chamfer 270 is disposed near the edge of the downstream surface 290.
  • the four surfaces 255 are disposed substantially perpendicularly to each other, around the mounting cap 210.
  • the base member 230 comprises of a side chamfer 205 that is disposed near a flat surface 215.
  • a thread 245 is disposed near a cylindrical surface 225, which is situated towards the edge of a flat surface 235.
  • the thread 245 comprises of a plurality of grooves to facilitate connection to a water source.
  • a thread 275 is situated at the opposing end of thread 245 to facilitate connection to the mounting cap 210.
  • a cylindrical surface 225 is disposed near the flat surface 235, a side chamfer 265 and another cylindrical surface 255.
  • Figure 3A shows a perspective front view of the nozzle 220 in an example embodiment.
  • Figure 3B shows a perspective rear view of the nozzle 220 in an example embodiment.
  • the nozzle 220 is cylindrical in shape.
  • the nozzle 220 comprises of an downstream surface 415, a upstream surface 425 and a peripheral surface 420.
  • the downstream surface 415 is parallel to the upupstream surface 425.
  • the downstream surface 415 comprises of an recess 450a that is indented across the downstream surface 415 from one end to the other end.
  • the recess 450a in this example embodiment has substantially perpendicular side walls with respect to the downstream surface 415.
  • a chamber 450 is formed in the recess 450a.
  • the chamber 450 is a substantially V groove.
  • a chamfer 430 is disposed near the edge of the downstream surface 415 and along the edges of the recess 450a.
  • a chamfer 430a is disposed near the edge of the upstream surface 425.
  • a chamber 475 is disposed centrally in the upstream surface 425.
  • the first chamber 475 comprises of a frusto-conical portion 440, a cylindrical recess portion 480 and a substantially conical portion 490.
  • An elliptical orifice 470 is located in the nozzle 220.
  • the elliptical orifice 470 is disposed in the substantially V groove 450, which is formed in the recess 450a.
  • the rear view of the elliptical orifice 470 can be seen in Figure 3B.
  • the elliptical orifice 470 is the meeting point whereby the substantially V groove 450 converges with the substantially conical portion 490.
  • the elliptical orifice 470 is shaped like a 'horizontally bent ellipse' in the example embodiment, instead of a "flat" round shape if the substantially conical portion would converge with a horizontal surface.
  • intersection of the substantially V groove 450 and the substantially conical portion 490, in defining the elliptical orifice 470 also determines the spray angle from the nozzle 220.
  • different spray angles can thus be achieved. Instead, a round orifice would create a round water jet stream with substantially zero spray angle (straight water jet).
  • Diameter of the elliptical orifice d mm ( (2.77 x Q 2 ) ⁇ P )° 25
  • P and Q are typically determined by the quality requirements of de- flashing of the semiconductor packages. For example, since semiconductor packages come in different sizes, nozzles with different specifications can be provided depending on different applications. Generally, there is a balance with high pressure resulting in the lead portion of a semiconductor package to bend, and lower pressure resulting in poor quality of the de-flashing.
  • Figure 4 shows a top view of the nozzle tip 220.
  • the major axis of the elliptical orifice 470 is substantially parallel to the recess 450a.
  • Figure 5A shows a side cross-sectional view of the nozzle 220.
  • the substantially V groove 450 is disposed near the downstream surface 415 while the substantially conical portion 490, the cylindrical recess 480 and the frusto-conical portion 440 are disposed near the upstream surface 425 of the nozzle 220.
  • the proportion of the substantially V groove 450 and the proportion of the frusto-conical portion 440, the cylindrical recess 480 and the substantially conical portion 490 can be seen in Figure 5A, marked A and B respectively.
  • the depth of the substantially V groove 450 is smaller than the depths of the substantially conical portion 490, the cylindrical recess 480 and the frusto-conical portion 440 combined.
  • the water source enters the nozzle assembly 200 from the base member 230, flows through the nozzle 220 and exits the nozzle assembly 200 from the mounting cap 210.
  • Figure 5B shows another side cross-sectional view of the nozzle 220.
  • the pressure of the water decreases as its velocity increases and vice versa.
  • the pressure and velocity are inversely proportional to one another.
  • the Bernoulli effect can be considered to be a statement of the conservation of energy principle as applied to flowing fluids.
  • the qualitative behaviour that is usually labelled with the term "Bernoulli effect” is the lowering of fluid pressure in regions where flow velocity is increased.
  • the following Bernoulli equation may be derived.
  • the fluid pressure in Section B of Figure 5B where the flow velocity increases is therefore lower than in Section A of Figure 5B, which exhibits higher pressure and lesser kinetic energy. Therefore, the nozzle 220 in this example embodiment can advantageously reduce the fluid pressure at and around the elliptical orifice 470, thereby reducing wearing of the diamond coating 460, 460a in that area. Hence advantageously, the lifespan of the nozzle 220 can be prolonged.
  • the surfaces of the recess 450a, the substantially V groove 450, the frusto-conical portion 440, the cylindrical recess 480 and the substantially conical portion 490 are coated with a layer of a hard material such as, but not limited to, diamond particles.
  • a layer of fine diamond particles is coated onto the recess 450a, the substantially V groove 450, the frusto-conical portion 440, the cylindrical recess 480 and the substantially conical portion 490 by using known methods, including but not limited to e.g. ionization, to form a diamond coating 460, 460a, as shown in Figure 5A.
  • the nozzle 220 is first charged and diamond particles are ionized to facilitate the bonding of the diamond particles to surfaces of the recess 450a, the substantially V groove 450, the frusto-conical portion 440, the cylindrical recess 480 and the substantially conical portion 490, to form a layer of diamond coating 460, 460a.
  • This layer of diamond coating 460, 460a is approximately 3 microns thick in this example embodiment. The entire coating process is controlled by the density of the carbon molecules in the diamond particles.
  • the hard material such as diamond, in this example embodiment, used to coat the surfaces of the recess 450a, the substantially V groove 450, the frusto-conical portion 440, the cylindrical recess 480 and the substantially conical portion 490 can advantageously prolong the lifespan of the nozzle 220 substantially.
  • the coating 460, 460a serves as a protective layer on the recess 450a, the substantially V groove 450, the frusto-conical portion 440, the cylindrical recess 480 and the substantially conical portion 490, against the strong thrust of the water spray.
  • the diamond particles are not easily dislodged.
  • this substantially reduces the manufacturing costs of the nozzle 220.
  • Figure 6A shows the high-pressure water jet nozzle assembly 200, spraying water 720 at a high-pressure, against unwanted flashes 710 to remove them.
  • the water 720 is being forced out of the nozzle assembly 200 at an angle to target at the key area, i.e. the unwanted flashes 710.
  • Figure 6B shows the relationship between the water 720 sprayed at an angle 730, a distance 740 of the water spray and a target area 750.
  • the angle 730 is 30° the length of the water spray distance 740 is approximately 15mm, while the target area of the water spray is approximately 7.5mm. This means that the water spray can be targeting unwanted flashes 710 with a surface length 750 of about 7.5mm.
  • Figure 7 shows a graph illustrating pressure against flow rate for one example nozzle design. It will be appreciated similar charts can be created for different nozzle designs. Since different products typically need different pressure ranges for effective deflashing, such data presentation charts can provide a a convenenient reference for determining/choosing a suitable a design for a particular product, and for facilitating determination of the supply size based on number of nozzle, type of nozzle and working pressure.
  • Figure 8 shows a flow chart 800 illustrating a method of fabricating a water jet nozzle according to an example embodiment. At step 802, a main body formed from a first material is provided.
  • a downstream surface comprising an orifice is formed; and at step 806 an upstream surface comprising a chamber extending towards the orifice is formed.
  • at step 808 at least a circumferential wall defining the orifice is coated with a second material, the second material having a greater hardness compared to the first material.
  • the described embodiment can provide a water jet nozzle that has a number of advantages over existing designs, including
  • the chamber design in the upstream surface leading to the orifice can assist in reducing the impact force on the hard material coating, thus further increase life time of the nozzle
  • the orifice design can result in a diverting spray for selecting different design options for a working distance and area of de-flashing.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Nozzles (AREA)

Abstract

L'invention porte sur une buse d'éjection d'eau, sur un procédé de fabrication d'une buse d'éjection d'eau et sur un procédé d'évaburage. La buse d'éjection d'eau selon l'invention comprend un corps principal formé dans un premier matériau; une surface aval comportant un orifice; et une surface amont comprenant une chambre qui s'étend vers l'orifice. L'invention est caractérisée en ce qu'au moins une paroi circonférentielle définissant l'orifice est revêtue d'un second matériau, ledit second matériau possédant une dureté supérieure à celle du premier matériau.
PCT/SG2008/000217 2008-06-20 2008-06-20 Buse d'éjection d'eau à haute pression résistante à l'usure WO2009154567A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/SG2008/000217 WO2009154567A1 (fr) 2008-06-20 2008-06-20 Buse d'éjection d'eau à haute pression résistante à l'usure

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/SG2008/000217 WO2009154567A1 (fr) 2008-06-20 2008-06-20 Buse d'éjection d'eau à haute pression résistante à l'usure

Publications (1)

Publication Number Publication Date
WO2009154567A1 true WO2009154567A1 (fr) 2009-12-23

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2014111542A1 (fr) * 2013-01-21 2014-07-24 Syngenta Participations Ag Procédé et appareil de pulvérisation de surfaces de sol
WO2015108838A1 (fr) * 2014-01-20 2015-07-23 Kmt Waterjet Systems Inc. Orifice pour outil de découpe au jet d'eau
CN106425889A (zh) * 2016-12-15 2017-02-22 贾跃民 新型的高压含沙水射流喷嘴总成
EP4299246A1 (fr) * 2022-07-01 2024-01-03 The Boeing Company Buse de cavitation tolérante aux dommages

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0430858A2 (fr) * 1989-12-01 1991-06-05 Possis Corporation Dispositif de buse pour de l'eau à ultra-haute pression
JPH11254327A (ja) * 1998-03-12 1999-09-21 Toshiba Tungaloy Co Ltd 耐久性に優れた中空構造体およびその製造方法
US6019298A (en) * 1992-12-08 2000-02-01 Flow International Corporation Ultrahigh-pressure fan jet nozzle
US7124967B2 (en) * 2003-12-22 2006-10-24 Jettech Ltd. Fan jet nozzle for use with ultra high pressure liquid phase cleaning media for use in deflashing apparatus
EP1908550A2 (fr) * 2001-08-27 2008-04-09 Flow International Corporation Appareil pour générer un jet de fluide haute pression

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0430858A2 (fr) * 1989-12-01 1991-06-05 Possis Corporation Dispositif de buse pour de l'eau à ultra-haute pression
US6019298A (en) * 1992-12-08 2000-02-01 Flow International Corporation Ultrahigh-pressure fan jet nozzle
JPH11254327A (ja) * 1998-03-12 1999-09-21 Toshiba Tungaloy Co Ltd 耐久性に優れた中空構造体およびその製造方法
EP1908550A2 (fr) * 2001-08-27 2008-04-09 Flow International Corporation Appareil pour générer un jet de fluide haute pression
US7124967B2 (en) * 2003-12-22 2006-10-24 Jettech Ltd. Fan jet nozzle for use with ultra high pressure liquid phase cleaning media for use in deflashing apparatus

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN *

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2014111542A1 (fr) * 2013-01-21 2014-07-24 Syngenta Participations Ag Procédé et appareil de pulvérisation de surfaces de sol
JP2016504969A (ja) * 2013-01-21 2016-02-18 シンジェンタ パーティシペーションズ アクチェンゲゼルシャフト 地表面に噴霧するための方法および装置
US9630189B2 (en) 2013-01-21 2017-04-25 Syngenta Participations Ag Method and apparatus for spraying ground surfaces
WO2015108838A1 (fr) * 2014-01-20 2015-07-23 Kmt Waterjet Systems Inc. Orifice pour outil de découpe au jet d'eau
US9808909B2 (en) 2014-01-20 2017-11-07 Kmt Waterjet Systems Inc. Orifice for a waterjet cutter
CN106425889A (zh) * 2016-12-15 2017-02-22 贾跃民 新型的高压含沙水射流喷嘴总成
EP4299246A1 (fr) * 2022-07-01 2024-01-03 The Boeing Company Buse de cavitation tolérante aux dommages

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