Mounting/Assembly

Are there any recommended soldering conditions for the N13T2 ?

Solder the N13T2 in the same way as a THD (Through-Hole Device).
For the specific soldering conditions, see the following website.
Semiconductor Device Mount Manual  3.3.3 Recommended temperature profile for each soldering method

When the recommended soldering conditions indicate that the number of times of mounting is "2", does this mean that a mounted device can be removed once and remounted?

No, it is not assumed that a mounted device will be removed.
If the number of times of mounting is "2", it means that, in normal processing, the soldering machine will execute soldering twice. For example, after soldering a device on the top of a board, it is possible for another device to then be soldered on the bottom of that board. With this kind of processing, for a device for which the number of times of mounting is restricted to 1, the latter processing (soldering on the bottom of the board) must be applied.

Are there recommended conditions for mounting a surface mounting-type device with a soldering iron?

Laser heating is recommended for pin partial heating of a surface mounting-type device, except for some products, because heat is directly applied to the semiconductor device, and a pin row must be heated within 3 seconds.
If this condition cannot be satisfied when a soldering iron is used, consult NEC Electronics through your distributor.

(2007/04)

How do you judge whether the solder dip method is appropriate or not?

The method of immersing a whole board in a solder vat is not recommended. Neither is wave soldering recommended for packages such as SOJ and BGA of which solder penetration is problematic, and for surface-mount packages with a lead pitch of less than 0.65 mm, where solder bridges can be made.
Neither is the solder dip method recommended for lead-free products that include metals other than solder, such as bismuth, used to plate the pins.

(2007/11)

How can I find out the moisture sensitivity level (MSL) of a product? Is it defined in any documentation?

NEC Electronics doesn't specify the moisture sensitivity level (MSL) as defined by J-STD-020 in any documentation.
However, the baking time and the number of storage days after opening the dry pack are defined by symbols under the recommended soldering conditions.

(2006/03)

The recommended soldering conditions of some products include the indication "prebaking". What does this mean?

When a product that is sealed in a plastic package is stored in the air, the package absorbs moisture from the air. When the package is then heated and mounted on the board by infrared reflow or VPS, it is subject to high temperatures in excess of 200°C. Since this causes the internal moisture to suddenly vaporize, and the package to expand, it possibly leads to cracks in the package.
Prebaking is a process whereby packages are baked before mounting to release this moisture, thus avoiding this problem.
For details on prebaking, see 3.2 Heat Resistance in the Semiconductor Device Mount Manual.

Products that require prebaking are shipped in dry packs with a moisture-proof aluminum coating.
After opening the dry pack, prebake the product under the conditions recommend for that product as required.

(2006/04)

Why do the prebaking conditions differ among products? And why do some products not require prebaking?

Different products have different packages and internal chip sizes, so the vulnerability of moisture absorption and cracking differs depending on these factors.

(2006/04)

What is the difference between preheating and prebaking?

Preheating means heating up the semiconductor device ready for mounting and must be carried out using a mounting machine.
Prebaking means baking the semiconductor device before mounting in order to remove any residual moisture. This does not need to be performed for semiconductor devices that have just been removed from their dry pack or for semiconductor devices that don't require anti-moisture control.



For more detailed information on mounting, please see the Semiconductor Device Mount Manual.

(2007/06)

Please tell me the device cleaning conditions.

Please refer to the following manual that describes about cleaning of devices.
Semiconductor Device Mount Manual  1.5.5 Cleaning

It is said that RA type rosin flux has strong corrosion behavior. But some flux manufacturers recommend it as non-cleaning flux.
Are there different types of RA type rosin flux?

Rosin flux is largely divided into three types, RA, RMA, and R, by order of activation.
Among these, RA and RMA may in some cases include halogens to improve solderability.
In the case of RA in particular, halogen residue remains after soldering, and causes degradation in reliability through corrosion, dendrites, etc.
However, recently, a large number of non-cleaning fluxes with high reliability that improve activation without active elements such as halogens, have been developed.
One index that expresses flux reliability is the chlorine content/halogen content, and this information is marked as a product characteristic for fluxes and pastes. So check this information in the documentation for solder pastes and fluxes that you plan to use, or inquire with the manufacturer.

Even in the case of pastes and fluxes that are described as a non-cleaning type, such products may cause problems depending on the quality level of the product. So the use of measures according to the quality level of the product for which paste or flux is to be used is recommended.

Do the soldering conditions for lead-free products differ from those of conventional products?

In general, it is different. But some conventional products meet the lead-free soldering conditions.
For the soldering conditions of lead-free products, refer to Lead-free Semiconductor Product Pamphlet.
For the soldering conditions of each product, either refer to their respective data sheets, or ask to the distributor.

I plan on mounting lead-containing products and lead-free products in mix on the same board. Are there any cautions I should observe?

(1) Soldering using lead-containing paste

(2) Soldering using lead-free paste

Why can't some products be soldered with the wave soldering method, as the result of the change to lead-free products?

Wave soldering is not recommended, because metals other than solder, such as bismuth, which are included in materials for plating, such as Sn-Bi allay, can contaminate mounting machines.

(2007/11)

The data sheets of ICs do not include the mount pad dimension of the PWB using the surface mount type packages.
Is this information available?

This information is available at the following location in the IC package homepage:
Technical information of IC package > List of IC packages

Click the check mark in the [Land pattern] box for the package in question to view the pattern figure.
For the optical devices and RF & microwave devices, refer to the documents on the following pages.

Photocoupler	:	10.4 LAND PATTERN DIMENSIONS in NEPOC SERIES PHOTOCOUPLER AND OPTICAL COUPLED MOS FET SELECTION GUIDE http://www.ncsd.necel.com/opto/english/document.html#Photocoupler
RF & microwave devices	:	PACKAGE LINE-UP FOR RF AND MICROWAVE DEVICES (for CAD data) http://www.ncsd.necel.com/microwave/english/document.html#pkg

(2007/04)

I would like to use Through-Hole-Device (THD) lead wire by bending it. Is there anything I should be careful about?

When bending the lead wire, do not apply tensile stress to the base of the lead.
To ensure this, securely fix the base of the lead by using the jig, and the jig does not touch the body of the device (interval of approx. 2 mm). Moreover, keep the curve within 90 degrees, and bend the lead wire only once.
Also, absolutely never perform bending that would cause the lead interval to increase.

I am considering applying a moisture-proof coating to my device after mounting it on the board. Can you recommend coating methods, and are there any points I should note when doing this?

NEC Electronics uses an epoxy resin for the packages of semiconductor devices. Make sure that the coating material has an equivalent thermal expansion coefficient to the epoxy resin, so that it does not cause mechanical stress.

Common practice is to apply a (rubber-like) buffer agent before applying the external coating to avoid causing thermal or mechanical stress.

Caution RF & microwave device characteristics may be degraded by the coating processing.

(2007/04)

I have heard that semiconductor devices are vulnerable to static electricity, but just how should I take care when mounting them?

The packing materials, trays, etc., used during shipping are all conductive so as to avoid the effect of static electricity.
During mounting of the semiconductor devices after unpacking, antistatic measures must be implemented for all operators and tools in your processes.
If static electricity is applied to the pins of the device, even if destruction does not occur at that time, defects may occur after the device is shipped to market due to heavy damage.

   Reference material:
    Guide to Prevent Damage for Semiconductor Devices by Electrostatic Discharge (ESD)

(2007/10)

Is there any information concerning metal masks used for application of solder paste when a semiconductor device is mounted by reflow soldering?

No. Semiconductor device manufacturers do not have information on metal masks. Mask opening dimensions and thickness are determined in the mounting process depending on the solder paste to be used and the characteristics of the mounter.

(2008/04)