3D PLUS a plus de 200 000 composants microélectroniques dans l’espace, et plus de 20 ans d’expérience de vol sans aucune défaillance signalée. Notre patrimoine de vol se développe continuellement avec des produits lancés dans l’espace tous les mois en orbites LEO, MEO et GEO, pour des missions d’exploration de l’espace lointain, pour des flottes de constellations de satellites, et pour des missions gouvernementales en Europe, en Amérique et en Asie. Nos missions phares comprennent Mars 2020, Mars Science Laboratory, Rosetta, New Horizons, Juno, OneWeb, AlphaSat, Sentinel, Ariane 5, ISS, Parker Solar Probe, Insight, et bien d’autres encore.
Frequently Ask Question (FAQ) have been chosen from typical interrogation we gathered from various customer worldwide. The list of question and answers will be updated, as soon as 3D PLUS feels it is necessary to provide a global answer to the users. The questions are posted in orange when the answers underneath are in black. All questions and answers are doubled in pdf attached next to them.
3D PLUS has clear recommendation for Flux type, they can be found in the 3D PLUS assembly recommendation.
Nevertheless 3D PLUS can still support some specific request from customers.
FLUX ROL 0 is preferred, without halides such as 17CI,9F, 35Br, 53I and 85At.
3D PLUS has clear recommendation for solder paste to reflow 3D PLUS module on board, they can be found in the 3D PLUS assembly recommendation.
Nevertheless 3D PLUS can still support some specific request from customers.
We could not achieved a good quantity of solder behind the lead? We could not achieve to get a good wetting at the lead heel?
Answer: In manual assembly 3300-1300, many parameters should help:
For information, 3D PLUS can propose training about handsoldering on site. Please contact 3D PLUS for more information about training conditions.
Can you please clarify what is the H measurement from the picture below, from the report 3300-1303?
Answer: H is called “stand-off” or “elevation” – this is the distance between the leads and their pads. This space must be filled with solder alloy, and must be strictly positive : a good practice is to guaranty 100µm (at least 50µm), in order to improve reliability of solder joints and to ease the handsoldering.
A 100µm caliper of epoxy film can be used as spacer between the leads and the board.
Would you please tell us some parameters about 3D PLUS module lead integrity? How much force can be placed from top of module without broken the leads? How much force placed on leads can break the leads?
Answer:The lead integrity we perform does not address such point, described in your questions; we look for numbers of bending and associated angle, but not the force that can support the module and its leads
Other parts cannot stand a 125°C exposure baking before module removal. What are the other baking conditions at lower temperature?
Answer:Please, see the recommendations delivered with 3D PLUS parts.
How to define the stencil for solder paste printing?
Answer:Aperture shape : oblong with 10% margin on width
Thickness : depends on needed volume of solder paste – 150µm, 175µm or 200µm are common values – take care : if the stencil gets too thick, there is a risk that the solder paste sticks to the stencil walls
Feel free to contact the manufacturer of the solder paste for more information or recommendations.
The following table is based on technical information about material compatibilities from manufacturers.
Except for IPA, the following cleaning agents have never been tested by 3D PLUS.
(Nota: Whatever the cleaning agent is, the usage of ultrasonic cleaning machine is not recommended, according to ESA Standards ESCC-Q-ST-70-08).
C = should be compatible
C/T = should be compatible, but a test on mechanical sample is recommended.
NR = Not recommended (SOP bottom varnish or body coatings may react at contact with cleaning agent : dissolution, swelling, peeling…)
Note1: Never been tested by 3D PLUS, customer experience is welcome
Note2: recommended primer to be applied prior coating.
Answer: Answer from the manufacturer MAP (Mapsil213B) :
“The Mapsil is a Polyaddition-type silicone elastomer, which doesn’t reject any acetic acid or anything else, unlike a polycondensation-type silicone elastomer.
Main properties are : space certified, low RML/TML/CVCM, no reject of any corrosive agents and a low volume reduction during curing.
The coating is “resistant” to acetic or alcoholic solutions, but the concentration of solutions and the exposure duration into these solutions must be taken into account.
In case of doubt, some experiment must be performed with same conditions as end-user”
Answer: The varnish Mapsil213B is an European space-qualified silicone-based coating. This coating is compliant to 3D PLUS’ PID.
More information are available on request or on MAP’s site www.map-coatings.com .
Answer: The varnish Solithane 113 is an European space-qualified urethane-based coating. This coating is compliant to 3D PLUS’ PID. More information are available on request
Answer: The varnish Arathane 5750-A/B is a US space-qualified urethane-based coating. This coating is NOT compliant to 3D PLUS’ PID. More information are available on request
Answer: The varnish Epo-Tek 302-3M is a coating dedicated for military application (salt fog, …). This coating is NOT dedicated to space application, then it’s NOT compliant to 3D PLUS’ PID. More information are available on request
Answer: 3D PLUS has only tested the following 4 varnishes : Mapsil213B, Solithane 113, Arathane 5750-A/B, Epo-Tek 302-3M. Due to Gold finish, it is highly recommended to ask the manufacturer for any primer associated with the specific varnish.
IPA cleaning is compatible with an Arathane 5750 A/B coating (and with all other optional coatings proposed by 3D PLUS).
Answer from SP&S Inc (Arathane 5750 A/B distributor):
“Once fully cured, the Arathane 5750A/B(LV) is completely resistant to IPA. We have many, many reports from customers who are using IPA or IPA/water blends for cleaning PCBs coated with the Arathane 5750 and to-date haven’t heard of any problems.
We’ve also done a 90 days full immersion study in a 70% IPA/30% water blend and saw no significant changes in properties for the Arathane 5750.”
If any peeling is observed after coating and cleaning, take care of :
1.Ensuring that the module is clean and dry prior to applying the Arathane 5750
2.A primer is recommended to apply onto the parts before varnish – A modus operandi is available from your 3D PLUS contact on demand (only English version)
3.Whenever possible, it is better to apply 2 thin coating layers rather than 1 thicker layer
There is a compatibility problem of stickiness between MAPSIL 213B and polyurethane varnish:
Mapsil 213B varnish is a silicone based coating – the polyurethane might not stick the Mapsil coating.
Instead Mapsil 213B coating, 3D PLUS can propose the Solithane113 (covered by our ESA certified PID) or the Arathane 5750A/B (urethane based coating), which is US space qualified (but not covered by our ESA approved PID).
Answer from SP&S Inc (Solithane 113 or Arathane 5750 A/B distributor):
“Yes, the general phenomenon of yellowing/darkening will be the same for the Arathane 5750 and the Solithane S113/C113-300. However there are chemical differences between the systems that will play a role in how quickly and to what extent the phenomenon is seen.
In general, yellowing and darkening is often related to the number of aromatic rings and double bonds in the polymer structure. The Solithane S113 and Arathane 5753 are both are based on isocyanates that have aromatic rings, so both have the potential for yellowing with exposure to higher temperatures. The Arathane 5753B(LV) also contains a significant number of double bonds which are also subject to thermal to thermal rearrangement and can increase the yellowing effect. The Solithane C113-300 does not contain a significant number of double bonds, and this makes formulations of the Solithane that contain large amounts of the C113-300 somewhat less susceptible to yellowing when exposed to temperatures above about 120°C.
There are other secondary effects that cause almost all organic molecules in polymers such as urethanes, epoxies, etc. to yellow when exposed to higher temperature for extended periods, but for these particular systems the mentioned chemical structures are likely to be the ones most directly involves. The primary reason for yellowing/darkening will be oxidation, so heat exposure in an inert environment (i.e. under vacuum, under dry nitrogen or argon, etc.) will minimize these types of effects.”
Answer: We do not recommend use of FONDAM mask on 3D PLUS parts. It may let some mask residues in insulation kerf between tracks. Even if the manufacturer of FONDAM guarantees that residues won’t affect conductivity nor corrosion, 3D PLUS cannot guarantee its compatibility.
3D PLUS can propose other solutions like coating (optional).
Answer: We never used this coating before, and 3D PLUS finds too difficult to offer this coating on modules (primer, adherence test, safety for staff…).
However, this material has similar physical properties with Arathane 5750 (see both TDS) – Urethane based coating, compliant with MIL-I-46058-C, Type UR – and IPC-CC-830.
3D PLUS can propose to send some mechanical samples with Arathane Coating for the customers to test compliance with the Conathane.
Answer: Many experiments on 3D PLUS modules show that the Parylene is compatible with modules (Parylene C,D or N). Due to its coating mode, 3D PLUS cannot provide such coating on individual parts.