Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01C—RESISTORS
  • H01C7/00—Non-adjustable resistors formed as one or more layers or coatings; Non-adjustable resistors made from powdered conducting material or powdered semi-conducting material with or without insulating material
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01C—RESISTORS
  • H01C1/00—Details
  • H01C1/14—Terminals or tapping points or electrodes specially adapted for resistors; Arrangements of terminals or tapping points or electrodes on resistors
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01C—RESISTORS
  • H01C17/00—Apparatus or processes specially adapted for manufacturing resistors
  • H01C17/28—Apparatus or processes specially adapted for manufacturing resistors adapted for applying terminals
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T29/00—Metal working
  • Y10T29/49—Method of mechanical manufacture
  • Y10T29/49002—Electrical device making
  • Y10T29/49082—Resistor making

Definitions

• Resistor in particular SMD resistor, and associated
• the invention relates to a resistor, in particular an SMD resistor, as well as a corresponding manufacturing method according to the independent claims.
• FIG 4 shows an exemplary embodiment of a conventional SMD resistor 1 (SMD: S_urface mounted device), which is sold by the applicant and in similar form, for example, in DE 43 39 551 Cl is described.
• the known SMD resistor 1 has a plate-shaped metallic carrier 2, which may for example consist of copper.
• an electrically insulating adhesive layer 3 is applied in the manufacture, with which then a resistive layer is glued to the top of the carrier 2.
• the resistance layer is structured by etching, so that forms a maanderformig extending resistance track 4 at the top of the carrier 2.
• the resistor 1 is then covered at the top by a protective lacquer 5 which electrically insulates the resistance track 4.
• a transversely extending recess 6 is then introduced into the carrier 2, which divides the carrier 2 into two separate carrier elements 2.1, 2.2 and thereby prevents a direct current flow between the two carrier elements 2.1, 2.2.
• the support elements 2.1, 2.2 in this case thus form the electrical connection parts of the SMD resistor 1, which can be soldered on solder pads 7, 8, as indicated schematically in the drawing by the arrows.
• a disadvantage of the known SMD resistor 1 is the complicated electrical connection of the underlying support elements 2.1, 2.2 with the above-adhered resistance layer, which forms the resistance track 4.
• a conductive surface must first be achieved (chemical through-connection) in preparation for a current-carrying, galvanically applied contacting on the outer edge of the adhesive layer 3, in order subsequently to apply a copper layer in a multi-stage galvanic process, which safely conducts the total current.
• this contact is part of the current path through the SMD resistor and therefore also influences the resistance of the SMD resistor 1, which in the case of low-resistance configurations with a resistance value of less than 25 m ⁇ requires that the resistance compensation be performed on the isolated SMD resistor 1 whereas resistance matching on a multi-resistor benefit is excluded.
• a further disadvantage of the known SMD resistor 1 is due to the incision 6 in the carrier 2, since the recess 6 for the mechanical stabilization of the SMD resistor 1 is filled with a lacquer or an epoxy resin which expands during the plating and for Bending of the SMD resistor 1 leads, wherein the bending is virtually frozen after the solidification of the solder and is retained in the finished component, at least as an optical defect.
• This problem occurs especially when using lead-free solders that require a higher soldering temperature.
• a certain paint volume is required to mechanically stabilize the SMD resistor 1 despite the incision 6, which in turn requires that the carrier 2 is relatively thick.
• the carrier 2 must have a thickness of at least 0.5 mm, which limits the miniaturization of the SMD resistor 1. Regardless of the thickness of the carrier 2, the mechanical strength of the SMD resistor 1 due to the mechanical weakening is limited by the incision 6.
• SMD resistor 1 Another disadvantage of the SMD resistor 1 is the high electroplating cost, which accounts for approximately 25% of the total production costs. These high electroplating costs result from the fact that the lateral re-contacting of the two support elements 2.1, 2.2 to the resistance track 4 must take over the full current flow, so that the requirements for the density and the effective cross section of the galvanically applied copper layer are relatively high. In addition, with low-ohmic resistance values, the influence of copper on the electrical properties is not completely negligible.
• the support elements 2.1, 2.2 do not correspond to the usual standard dimensions of solder pads as connection parts, but have a much greater length. A shortening of the two support elements 2.1, 2.2 and thus a widening of the incision 6, however, would lead to a further mechanical and thermal weakening and is therefore not possible.
• FIG. 5 shows another construction of a known SMD resistor 9 marketed by the Applicant, a similar construction also being described in EP 0 929 083 B1.
• the SMD resistor 9 has a plate-shaped thin carrier 10 made of aluminum, wherein the carrier 10 in this design has no incision and thus no mechanical weakening.
• At the bottom of the plate-shaped carrier 10 is an adhesive layer 11, a resistive layer 12th glued, the technically structured and forms a maanderformige resistance path.
• strip-shaped copper contacts 13 are applied to the underside, which contact the strip-shaped connecting parts 14, 15 electrically.
• the SMD resistor 9 in this construction at the top and at the bottom of a protective lacquer layer 16, 17.
• An advantage of this construction of the SMD resistor 9 is first the fact that the carrier 10 has no mechanical weakening, so that the problems based thereon and described above are avoided.
• connection parts 14, 15 and thus also the soldering points lie on the underside of the SMD resistor 9, where the solder points are not accessible to visual inspection.
• lateral attachment of the solder pads is not possible with the SMD resistor 9 because the solder pads would otherwise make an undesirable electrical shunt across the electrically conductive carrier 10.
• SMD resistor 9 Another disadvantage of the SMD resistor 9 is that the carrier 10 made of anodized aluminum is relatively hard and therefore reduces the lifetime of the used Sageblatts when separating the SMD resistor 9 by legends. Moreover, the rejection of the individual SMD resistors 9 from aluminum benefit, due to the low melting point of the aluminum compared to copper, leads to an interfering sawing ridge on the rejected SMD resistor 9.
• Another conventional construction of an SMD resistor finally has a plate-shaped ceramic carrier, which carries on its upper side a structured resistance layer, wherein the resistance layer also forms a maanderformige resistance path.
• the electrical contacting of the SMD resistor is carried out in this construction by Lotkappen of a chemicalleitfahigen, usually galvanically reinforced, solderable metal layer (eg nickel-chromium alloy), the Lotkappen in cross-section are U-shaped and the opposite narrow edges of the SMD Encase resistance-shaped cap.
• the Lotkappen are hereby accessible laterally, so that when Festloten laterally visible Lotstellen arise that allow easy visual inspection of the solder joints.
• a disadvantage of this construction is the fact that the carrier is made of ceramic and therefore compared to
• Copper see Fig. 4
• aluminum see Fig. 5
• the resistance layer is in this case arranged on the upper side of the carrier, which leads to the above-described disadvantageous influences on the total resistance.
• the object of the invention is to eliminate the disadvantages of the SMD resistor 9 by allowing a simple visual inspection of the solder joints.
• the invention comprises the general technical teaching of arranging the connection parts exposed on the resistor laterally, so that the connection parts are visibly wettable laterally by a solder in order to allow a visual inspection of the respective solder connection.
• the inventive resistor is preferably designed as an SMD resistor and allows a conventional surface mounting.
• the invention is not limited to SMD resistors, but basically also includes other types of Widertand, for example, provide a conventional contact with solder pins.
• the resistor according to the invention has a flat, metallic support element, which has good thermal conductivity and an adapted coefficient of thermal expansion due to its metallic material composition, which is advantageous during operation of the resistor according to the invention.
• the resistor according to the invention has a flat resistance element made of a resistance material, wherein the resistance element is arranged on the underside of the flat carrier element.
• a flat resistance element or carrier element is to be understood generally and is not limited to the mathematical-geometric definition of a surface.
• this feature is preferably based on the fact that the lateral extent of the carrier element or of the resistance element is substantially greater than the thickness of the carrier element or resistance element.
• this feature preferably also includes that the top side and the bottom side of the carrier element or resistance element each extend parallel to one another.
• the support element and the resistance element are preferably flat, but also curved and curved shapes are possible for the support element and the resistance element.
• the resistor according to the invention has at least two separate metallic connection parts, which electrically contact the resistance element and are partially arranged on the underside of the support element.
• the connection parts are not completely arranged at the bottom, but are at least partially laterally free of the resistor, so that form the solid solders laterally visible Lotstellen that a simple visual inspection enable.
• the metallic connecting parts preferably each extend laterally upwards on the resistor up to the metallic carrier element, where the connecting parts contact the carrier element and make electrical and thermal contact.
• the connecting parts can each have a U-shaped transverse have cut and embrace the resistor at opposite edges each kappenformig, with a lateral metallization in the contact area is possible.
• the metallic carrier element has only the function of a carrier and a heat conductor, whereas in the case of the inventive resistor the carrier element should not be a current conductor in order to avoid an undesired shunt across the metallic carrier element.
• the metallic element Tragerele ⁇ Therefore, in the inventive resistor an incision, which divides the support element into at least two electrically isolated portions and a current flow via the support element between the two connecting parts is prevented.
• the recess may be formed in the same manner as in the known SMD resistor according to Figure 4, in which the resistance layer is arranged at the top of the carrier.
• the incision in the support element runs at least partially obliquely, for example V-shaped, W-shaped or maander-shaped.
• V-shaped, W-shaped or maander-shaped Such a shaping of the incision in the support element advantageously leads to a greater mechanical stability of the resistance than in the case of a running incision.
• connection parts are preferably matched in their size to standard solder pads, as a result of which the resistor according to the invention differs from the known SMD resistor according to FIG. 4, in which the connection parts have a substantially greater lateral extent.
• the connecting parts therefore preferably have a lateral extent which is less than 30%, 20% or 15% of the distance between the two connecting parts.
• a relative dimensioning of the connecting parts relative to the distance between the connection parts on the other hand excessively klei ⁇ NEN connection parts.
• the strip-shaped connection parts can have a width in the range of 0.1-0, 3 mm (design 0402), 0.15-0, 40 mm (design 0603), 0.25-0.75 mm (design 1206) or 0.35- 0.85 mm (type 2512).
• the resistance material of the resistor according to the invention preferably consists of a copper-manganese alloy, such as, for example, a copper-manganese-nickel alloy.
• a copper-manganese alloy such as, for example, a copper-manganese-nickel alloy.
• CuMn3 be used as a resistor material.
• a nickel-chromium alloy in particular a nickel-chromium-aluminum alloy.
• the resistance element may also consist of a copper-nickel alloy, such as CuNil5 or CuNiIO.
• the invention is not limited to the abovementioned examples with regard to the resistance materials which can be used, but in principle can also be implemented with other resistance materials.
• the resistor according to the invention preferably has a high degree of miniaturization.
• the thickness of the resistor according to the invention may be less than 2 mm, 1 mm, 0.5 mm or even 0.3 mm.
• the length of the resistor according to the invention may be less than 10mm, 5mm, 2mm or even less than 1mm.
• the breadth of the invention By comparison, the resistance is preferably less than 5 mm, 2 mm or even less than 1 mm.
• the carrier element preferably has a thickness which lies in the range of 0.05-0.3 mm.
• solder resist a temperature-resistant insulating layer
• solder resist is therefore preferably applied to the upper side of the support element and to the lower side of the support element in the resistor according to the invention.
• connection parts preferably consist of a highly conductive material in order to achieve the lowest possible connection resistance.
• the carrier element and / or the connecting parts are preferably made of a highly thermally conductive material in order to achieve effective heat removal from the resistance element.
• the connection parts and / or the support element for this purpose may consist of copper or a copper alloy.
• the individual connecting parts are preferably cap-shaped and can be U-shaped in cross-section, for example.
• the U-shaped cross-section surrounds the upper leg of the connection part, the support member above, while the lower leg of the U-shaped connection part engages around the resistance element below.
• the cap-shaped connecting parts are preferably provided in the closing part that the cap-shaped connecting parts not only surround the support element and / or the resistance element at the top or bottom, but also laterally. This is possible if the cap-shaped connection parts are only applied when the resistors are separated from the use within the scope of the manufacturing method according to the invention, since only then are the lateral cut surfaces of the isolated resistors exposed.
• an adhesive layer is preferably arranged between the planar resistance element and the flat support element.
• the adhesive layer fixes the planar resistance element on the underside of the support element.
• the adhesive layer is electrically insulating and therefore prevents interfering electrical shunts on the metallic support element.
• the planar resistance element is preferably structured in a medical or other manner (eg by laser processing) so that the resistance element has a simple rectangular or maander-shaped resistance path, as is the case with the known SMD resist described in the introduction - stood the case.
• the resistor according to the invention advantageously enables low resistance values in the milliohm range, the resistance being less than 500m ⁇ , 200m ⁇ , 50m ⁇ , 30m ⁇ , 20m ⁇ , 10m ⁇ , 5m ⁇ or even less than 1m ⁇ .
• the resistance element in the case of the resistor according to the invention is preferably complete is electrically insulated to the outside, if one disregards the connection parts.
• the invention comprises not only the resistor according to the invention described above but also a corresponding manufacturing method in which the connection parts are attached to the resistor in such a way that the connection parts are exposed laterally and are visibly wettable by a solder. to allow a visual inspection of the respective soldering point.
• the incision in the metallic support element described above can be produced, for example, in the context of the manufacturing method according to the invention, by etching technology or by laser processing.
• the separation of the resistances by means of sawing, punching or laser cutting can be of use.
• the invention advantageously allows a longer service life of the saw blade used, since copper is much softer than the anodized aluminum used in the known SMD resistor described above according to FIG.
• the invention advantageously makes it possible to carry out a resistance compensation on a utility with a plurality of resistors that have not yet been isolated, so that after the separation of the resistors no resistance compensation is required.
• FIG. 1 shows a perspective view of an SMD resistor according to the invention
• FIGS. 2A-2G show various stages of manufacture of an SMD resistor according to the invention
• FIG. 3 shows the production method according to the invention in FIG.
• FIG. 4 shows the known SMD circuit described above.
• Figure 5 is a perspective view of the well-known SMD resistor also described above.
• the cross-sectional view in FIG. 1 shows an SMD resistor 18 according to the invention, which may have, for example, the 0604 design.
• the SMD resistor 18 may have a thickness in the Y direction of e.g. 0.4mm.
• the SMD resistor 18 has a plate-shaped carrier element 19 made of copper, wherein on the underside of the carrier element 19 by means of an adhesive layer 20 a resistance Layer 21 of a copper-manganese-nickel alloy (CuMnl2Ni) is glued.
• the adhesive layer 20 effects a fixation of the resistance layer 21 on the underside of the plate-shaped carrier element 19.
• the adhesive layer 20 is electrically insulating and therefore insulates the conductive carrier element 19 with respect to the resistance layer 21.
• the SMD resistor 18 has laterally cap-shaped connection parts 22, 23, wherein the two connection parts 22, 23 surround the support element 19 and the resistance layer 21 at the top, sides and bottom.
• the two connection parts 22, 23 thus contact the resistance layer 21 electrically, so that in the mounted state a current can flow via the two connection parts 22, 23 and the resistance layer 21.
• Parts 19.1, 19.2 are electrically isolated from the incision 24 against each other.
• the adhesive layer 20 between the resistive layer 21 and the plate-shaped support member 19 thus prevents in connection with the incision 24 interfering electrical shunts on the support member 19.
• the support member 19 thus serves only as a mechanical support and heat dissipation, but not to the power line.
• solder resist 25 is applied flatly to the upper side of the support element 19 between the two connection parts 22, 23.
• a solder resist 26 is also flatly applied to the underside of the resistance layer 21 between the two connection parts 22, 23.
• the resistance layer 21 is thus in the SMD resistor 18 except for the connection parts 22, 23 completely isolated to the outside.
• FIGS. 2A-2G showing various intermediate stages of the SMD resistor 18 according to the invention.
• the carrier element 19 is initially provided in the form of a copper foil, as shown in FIG. 2A.
• the resistance layer 21 is then glued to the underside of the carrier element 19, wherein the bonding takes place by means of the adhesive layer 20, as can be seen from FIG. 2B.
• Step S3 the incision 24 is then introduced into the carrier element 19, in order later to prevent an electrical shunt via the electrically conductive carrier element 19.
• the generation of the incision 24 can take place, for example, by medical technology or by laser processing.
• Step S3 leads to the intermediate stage according to FIG. 2C.
• step S4 a solder resist is then applied to the upper side of the support element 19, which is known per se.
• step S5 an etching-technical structuring of the resistance layer 21 takes place, which then subsequently forms a maander-shaped resistance path.
• step S6 the solder resist 26 is then applied to the underside of the resistive layer 21, as shown in FIG. 2D.
• a stripe-shaped exposure of the carrier element 19 then takes place at the edges of the SMD resistor 18 which are opposite in the X direction, so that subsequently the connection parts 22, 23 can contact the carrier element 19 thermally.
• the cross-sectional view m Figure 2E shows this state after the strip-like exposure of the support member.
• a step S9 the deposition of a copper layer having a thickness of e.g. lO ⁇ m on the exposed edges of the resistive layer 21 at the bottom.
• SlO then takes place at a benefit with numerous, not yet isolated SMD resistors a resistance balance.
• the individual SMD resistors 18 are then separated from the use in a step S, which can be done by sawing, punching or laser machining.
• FIG. 2G shows the SMD resistor 18 according to the invention on a printed circuit board 27 with two standard solder pads 28, 29 and two solder pads 30, 31. From the cross-sectional view it can be seen that the solder pads 30, 31 are located laterally on the PCB SMD resistor 18 are exposed and therefore a visual inspection are accessible.

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• Engineering & Computer Science (AREA)
• Microelectronics & Electronic Packaging (AREA)
• Physics & Mathematics (AREA)
• Electromagnetism (AREA)
• Manufacturing & Machinery (AREA)
• Apparatuses And Processes For Manufacturing Resistors (AREA)
• Details Of Resistors (AREA)
• Non-Adjustable Resistors (AREA)
• Control Of Electrical Variables (AREA)
• Secondary Cells (AREA)
• Macromolecular Compounds Obtained By Forming Nitrogen-Containing Linkages In General (AREA)
• Glass Compositions (AREA)
• Organic Insulating Materials (AREA)

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• 2006
  • 2006-12-20 DE DE202006020215U patent/DE202006020215U1/de not_active Expired - Lifetime
  • 2006-12-20 DE DE102006060387A patent/DE102006060387A1/de not_active Withdrawn
• 2007
  • 2007-10-18 AT AT07819122T patent/ATE436077T1/de active
  • 2007-10-18 EP EP07819122A patent/EP1941520B1/fr active Active
  • 2007-10-18 CN CN2007800252335A patent/CN101484952B/zh not_active Expired - Fee Related
  • 2007-10-18 CA CA002654216A patent/CA2654216A1/fr not_active Abandoned
  • 2007-10-18 MX MX2009000553A patent/MX2009000553A/es active IP Right Grant
  • 2007-10-18 PL PL07819122T patent/PL1941520T3/pl unknown
  • 2007-10-18 DE DE502007001025T patent/DE502007001025D1/de active Active
  • 2007-10-18 US US12/375,276 patent/US8013713B2/en active Active
  • 2007-10-18 BR BRPI0720449-3A2A patent/BRPI0720449A2/pt not_active IP Right Cessation
  • 2007-10-18 KR KR1020087031564A patent/KR101371053B1/ko active IP Right Grant
  • 2007-10-18 WO PCT/EP2007/009057 patent/WO2008055582A1/fr active Application Filing
  • 2007-10-18 JP JP2009541788A patent/JP5237299B2/ja active Active
  • 2007-10-18 ES ES07819122T patent/ES2329425T3/es active Active

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