Case I |
Case II |
Case III |
Case IV |
Danfoss A/S
OEM Manufacturer |
Grundfos A/S
OEM Manufacturer |
Bent Hede Elektronik
Electronics subcontractor for PCBs and assembly manufacturing |
Mekoprint A/S
OEM Manufacturer |
| Application: |
| An electronic thermostat for refrigeration application type ETC.
There were manufactured printed circuit boards with conductive adhesive and with solder. |
Electronics for pump control. |
1) ’Flowerpot’ spear to light-up it the plants needs
water.
2) FR-4 Substrate to a levelling instrument. |
A two-key switch with light emitting diodes. |
| Motivation: |
| To use electrical conductive adhesive as a solder replacement in
the production on the existing production equipment. |
As an alternative to solder as conductive adhesive. The substrate
is mounted with bare dies and SMD. The dies are mounted with conductive adhesive and the
SMD components with solder. As it is preferred to have only one component attach process
the SMD components were mounted with conductive adhesive as well as the bare dies. |
Manufacturing and assembly of 3 dimension ’substrates’
in plastic. The demand was a new mounting technology, as solder could not be used due to
the high temperature. Further, ’warnings’ from authorities of lead-free
electronic production has sharpened the interest of using conductive adhesive. |
Is using polyester substrates for keyboard switches. For low
temperature polyesters solder could not be used for the component mounting, therefore
electrical conductive adhesive was chosen. |
| Substrate: |
| a) FR-4 Printed Circuit Board substrate with 0.2 um gold over 4
umNickel b) FR-4 Printed Circuit Board substrate with HAL TinLead
Copper layer thickness on both ab. 1 ounce.
Dimension: 32 x 57 mm. Thickness: 1.5 mm
Double sided with PTH.
Smallest conductor width: 0.1 mm
Smallest insulation distance: 0.15 mm
Solder mask is only applied on the FR-4 substrate with tin lead conductors. |
Ceramic Substrate – Alumina, with thickfilm silver
conductors.
0.63 mm thickness.
Dimension: 1"x2".
2 layer thickfilm silver conductors seperated by a thickfilm insulating layer. Smallest
conductor width: 0.25 mm.
Smallest insulation distance: 0.25 mm |
a) 3D Moulded polycarbonate substrate. Conductors with < 0.2 um
gold over > 4um
nickel on 18 um copper plating. The conductors are depressed in the polycarbonate.
Dimension: 152 x 40 mm. Inclusive the 62 x 12.5 mm spear. Thickness: 2 mm
Smallest conductor width: 0.6 mm. Smallest insulation distance: 0.6 mmb)
FR-4 Printed Circuit Board with <0.2 um gold over > 4 um nickel.
Copper layer ~35 um. Dimension: 80 x 80 mm, thickness 1.5 mm Smallest conductor width: 0.3
mm. Smallest insulation distance: 0.4 mm. Solder mask is applied on the FR-4 substrate. |
Polyester laminate, single sided with two layer screen printed
polymer silver conductors separated by an insulation layer. A selective carbon print (on
top on silver conductors) for key switch (contact dome).
Dimensíon: 59 x 43 mm. (excl. the In/output conductor part) Thickness: 0.3 mm Smallest
conductor width : 0.6 mm
Smallest insulation distance : 0.5 mm (x,y direction)
Smallest insulation distance is estimated to be between the two printed conductor layer.
0(z-direction).
Conductors are protected by a folio glued to the polyester substrate. |
| Components: |
3 diodes, SOT 23 with tin-lead terminal finish. 1 ASIC, SSOP 24,
pitch 0.65 mm. With tin-lead terminal finish.
20 resistors size 0603.
1 resistor size 0805.
6 capacitors size 0805.
1 electrolytic capasitor Ø 8mm, height 10 mm.
All components with tin-lead terminal finish.
1 ’potentiometer’ leaded with tin-lead terminal finish. The terminal is cut and
bended for surface mounting.
1 relay leaded with tin-lead terminal finish. The terminal are cut and bended for surface
mounting. |
Tantal capacitor, size A (l x w x h, 3.2 x 1.6 x 1.6 mm)
Tantal capacitor, size B (l x w x h, 3.5 x 2.8 x 1.9 mm)
Capacitor, size 0805.
Filter, size 0805.
Components with tin-lead or tin terminal finish. Bare dies for wire bonding. 2 glass Melf
diodes. |
Components for the 3D substrate: 1 diode, 1206 size, with gold
terminal finish
1 IC, SOT 14, pitch 1.00 mm with tin-lead terminal finish.
Components for the FR-4 substrate are not specified (all with tin-lead finish).
Components for the 3D substrate:
4 resistors size 0805.
1 capasitor size 0805.
Tantal capacitor, size A (l x w x h, 3.2 x 1.6 x 1.6 mm)
All components with tin-lead terminal finish.
Components for the FR-4 substrate are not specified. |
12 diodes, 1206 size, with gold terminal finish 2
diodes, special chip size, with gold terminal finish. |
| Conductive adhesive: |
Namics XH9626
Solder paste for reference:
Sparkle: OZ 2062-221CM5-40-10DMK. SN62/Ag2/Pb36
Solder (for wave solder):
Boliden, SnPb for wave solder with Philips RF800 flux |
Ablebond 8175A
Namics XH9626
Amicon CE3511 |
Amicon 3504FP and Loctite 3880 |
EPO-TEK H20F
Non conductive adhesive was used to fix the components, as the used conductive adhesive
has low adhesion strength. Type and material are not disclosed. |
| Cleaning materials: |
| Isopropanol and Ethylmethylketone. |
Isopropanol |
Isopropanol |
Not disclosed. |
| Process: |
Stencil printing:
Materials.
For solder paste 150 um stainless steel stencil
For conductive adhesive, 100 um stainless steel stencil
Equipment: DEK 265 GS stencil printer.
Dispensing:
Needle 0.6 mm
Equipment: FUJI GL 5 |
Stencil printing:
100 um stainles steel stencil
Equipment: Automatic stencil printer (MPM UP 2000).
Process: Performed by the equipment. |
Dispensing:
Needle 0.4 mm
Equipment: Not disclosed
Process: Manual dispensing of the 3D substrate.
Automatic dispensing by the equipment of the FR-4 Substrate. |
Dispensing:
Material: See 3.3 Material. Needle 0.4 mm
Equipment: Not disclosed. Automatic equipment
Process:
1. dispensing: Non conductive adhesive (To fix the components mechanical to the
substrate).
2. dispensing: Conductive adhesive. (To connect the components electrical to the substrate
conductors). |
| Component mounting: |
Material: A tweezer for manual component mounting. Gloves.
Equipment: FUJI CP IV, FUJI CP IV-3, FUJI IP 1, FUJI QP 242.
Hole mounted components were hand mounted with the tweezer. |
Material: None.
Equipment: Automatic placement
Process: The component mounting were perforemed by the equipment (Fuji automatic
placement). |
Material: None
Equipmemt: Automatic SMD placer, Zevatech PM 850. |
Not disclosed |
| Curing: |
Equipment: Reflow Soldering: BTU VIP 70, convection.
Adhesive Curing: P SELECTA Serie 2000, convection.
Wave soldering: SEHO.
Reflow profile max. 220 C.
Wave solder temperature max. 245 C.
Forced cooling after soldering was applied
Curing profile max 130 C for 60 min. |
Equipment:
Process: The adhesive were cured according to manufacturer specification in a Box oven
with air circulation. |
Equipment: IR-furnace.
Process: The adhesive was cured according to manufacturers specification. |
Equipment: Furnace
Process: The adhesive were cured according to manufacturers specification |
| Cleaning: |
| Cleaning was not performed after the
solder and the adhesive process. |
Cleaning was not performed after the
adhesive process |
Cleaning was not performed after the
adhesive process |
Cleaning was not performed after the
adhesive process |