JPH1176738A - Low-humidity storehouse - Google Patents

Abstract

PROBLEM TO BE SOLVED: To extremely easily and surely store an IC package in a low-humidity storehouse with controllability by providing a means for indicating the dehumidifying time necessary to a stored article at a position related to the article and a means for reporting that the dehumidifying time has passed. SOLUTION: An indicating part 7 for indicating the experimentally obtained dehumidifying time necessary to an IC package placed on the shelf is provided to a shelf or on the outer face of the door 5 corresponding to the shelf, the inner face of a low-humidity storehouse 1, etc., for each of the shelves. Further, a timer is furnished for each of the shelves set correspondingly to the drying time indicated on the indicating part 7. When an output is generated in the timer, the indicating part 7 is flickered, the color is changed, or a light or sound signal is given. As a result, each of the IC packages is easily and surely controlled in accordance with the necessary storing time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a low-humidity storage,
The present invention relates to a low-humidity storage capable of managing storage time of stored articles.

[0002]

2. Description of the Related Art In general, the surface of an IC package used for an electronic device is molded with an epoxy resin or the like, and the molded resin easily absorbs moisture in the air.
When placing the C package on the printed wiring board and performing reflow soldering, use an infrared
Heat at 150C for about 150 seconds.

[0003] At this time, if moisture is contained in the mold resin of the IC package, the moisture instantaneously evaporates, and due to the steam pressure, the die pad portion inside the IC package and the mold resin are separated at the interface, and this steam is discharged to the outside. At this time, cracks enter the mold resin, causing various complaints.

[0004] If the moisture content of the IC package is 0.15% or more by weight, cracks occur in a state of almost 100%.

[0005] In order to prevent this phenomenon, in a conventional general method, an IC package is housed in a baking furnace for about 1 hour.
Baking was performed at 00 to 120 ° C. for 12 hours to remove moisture from the IC package.

According to this method, almost 100% of the water can be removed, but since the IC package is heated for a long time, the pins (connection terminals) are oxidized, and the soldering becomes poor during reflow soldering. This is causing connection failure. Further, if the IC package is not mounted immediately after baking, the IC package again adsorbs moisture in the air and needs to be baked again, which is very troublesome.

Therefore, at present, a low-humidity container having a relative humidity (RH) of 5% or less is made by a dehumidifying method using a desiccant, and the IC package is left in this for several hours to diffuse moisture in the IC package. Moisture is removed from the IC package.

In such a low-humidity storage, the desiccant is regenerated by a heater for a certain period of time, and at the time of the regeneration, the shutter is switched between the inside and the outside of the compartment to release the moisture adsorbed from the inside of the compartment to the outside. When the operation is completed, the shutter is switched to start absorbing moisture in the refrigerator, and thereafter, this cycle is repeated.

In general regeneration, the desiccant is heated at about 150 ° C. for about 30 minutes, and this regeneration is repeated about every 6 hours, and these operations are performed by a timer.

FIG. 4 shows the dehumidification data of the IC package. According to FIG. 3, I contained 0.2% water by weight.
By storing the C package in a 5% RH storage for 24 hours, 0.145% of water can be removed, and the water content at that time becomes about 0.055%, which is 0.1% of the crack generation attention area. % So that it can be implemented with confidence.

According to this method, since the IC package can be dehumidified at room temperature, there is an advantage that there is no problem of oxidation of the pins and that the IC package can be stored in the low humidity storage as it is even after dehumidification.

[0012]

However, the low-humidity storage as described above requires constant monitoring of the humidity in the storage for its management, and various types of IC packages are stored, so that what kind of type and how long can be stored. It is difficult to determine whether or not it has been stored. Therefore, the humidity is managed by a monitor, and the humidity data can be left in the memory so that it can be printed out when necessary, or connected to a personal computer etc. so that the memory card can be input to the personal computer and the low humidity storage It is necessary to be alerted if the humidity of the air rises due to some abnormality.

SUMMARY OF THE INVENTION An object of the present invention is to provide a low-humidity storage in which storage of an IC package in a low-humidity storage can be managed very simply and reliably.

[0014]

The low-humidity storage of the present invention comprises:
It is characterized by having display means for displaying the dehumidification time required for the stored article at a position related to the article, and notification means for notifying that the dehumidification time has elapsed.

The above-mentioned notification is made by blinking or color change, light or voice.

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

1 and 2, reference numeral 1 denotes a low-humidity storage,
Is a shelf plate, 3 is an article to be dehumidified placed on the shelf plate 2, for example, an IC package, 3 'is a tray containing the IC package, 4 is, for example, JP-A-6-304436.
No. 5, reference numeral 5 denotes a door provided corresponding to the shelf board 2, and reference numeral 6 denotes a glass window of the door 5.

In the present invention, as shown in FIG. 1, each of the shelves 2 is provided on the outer surface of the shelves 2 and / or the door 5 corresponding to the shelves 2 or on the inner surface of the low-humidity storage 1. A display unit 7 for displaying the minimum required dehumidification time obtained by an experiment in advance for the IC package 3 mounted on the display unit 7;
And a timer (not shown) for each shelf set in accordance with the drying time indicated in the above section. When the timer generates an output, the display section 7 blinks or changes color. Generate light and audio signals.

FIG. 3 shows another embodiment of the display unit 7 according to the present invention, wherein 8 is a shelf or door number display, 9 is a time display,
Reference numeral 10 denotes a reset button for a timer, 11 denotes a stored article display, and 12 denotes a button for setting a timer time, a shelf number, and the like.

In this embodiment, the time setting button 1
Press 2 to set the timer to the time when the humidity of the IC package 3 becomes the crack generation attention area, for example, 6 hours.
Set each time to be a safety area, for example, 12 hours,
When the designated time has elapsed, the color of the time display 9 can be changed at each elapsed time, or a different light or audio signal can be generated.

For example, in less than 6 hours after storing the article, it is displayed in red that the water content is in the vicinity of the crack occurrence caution area,
When 12 hours or more have passed, the fact that the vehicle is in the sufficient safety area is displayed in green or the like. Therefore, it turns out that the articles in the shelf and door where the green lamp is lit can be taken out and used for many days without any worry.

[0022]

As described above, the low-humidity storage of the present invention has a great advantage in that it can be easily and reliably managed according to the required storage time for each IC package. There is.

[Brief description of the drawings]

FIG. 1 is a front view of a low-humidity storage according to the present invention.

FIG. 2 is a side view of the low humidity storage of the present invention.

FIG. 3 is an explanatory diagram of a display unit in the low-humidity storage of the present invention.

FIG. 4 is a diagram for explaining a moisture absorption state of an IC package by a low-humidity storage.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Low-humidity storage 2 Shelf 3 IC package 4 Dehumidifier 5 Door 6 Glass window 7 Display part 8 Number display 9 Time display 10 Reset button 11 Stored goods display 12 Timer time, shelf number and other setting buttons

Claims (3)

[Claims] 1. A low-humidity storage device comprising: display means for displaying a dehumidification time required for a stored article at a position associated with the article; and notification means for notifying that the dehumidification time has elapsed. Warehouse. 2. The low-humidity storage according to claim 1, wherein the notification is made by blinking or color change. 3. The low humidity storage according to claim 1, wherein the notification is made by light or voice.