Material management

  1-1.  Material management 

1-1-1. Standards of BGA / IC / PCB Incoming & management :

[1] Incoming

   1) IC & PCB should be warehoused in vacuum packing.

[2] Inspection : Conduct inspection available in vacuum packing.

    1) When incoming BGA & PCB gets NG after inspection,

      - IQA inspector should inform the person in charge  and receive an order,

        or return to the maker if possible.

   ※ NG criteria

      - When parts are not in vacuum packing, or air flows in due to packing damage.

      - When actual parts are different to the details in inspection record by Maker.

    2) when appear the NG of components about vacuum packing, if NG components
        can not be return, after components baking and then processing the vacuum
        packing.

    3) If the validity of IC had expired, inform  Manager or return it.

        (Even more than one year IC in vacuum packing)

[3] Storage

    1) Must separate parts for ordinary & Pb free.

    2) BGA, IC & PCB must be stored in vacuum packing.

     ※ BGA and IC’s store standards must apply the criteria that attached IC packing

     ※ Standard of storage temperature/humidity : 25 ± 5℃,  50±10% 

    3) Store separately by lot for First-in, First-out (FIFO)

[4] Use

    1)Open IC envelope and PCB box before production.

    2)Remained IC & PCB after opening, vacuum pack in 30 minutes and store.
       (after 30 minutes, vacuum pack after Baking)

    3)After opening, operators must wear anti-static gloves and wrist strap to protect
       IC & PCB.

    4)Write down opening date and time on the envelope to prevent IC from absorbing
       moisture and PCB oxidation. And It should manage envelope and tray
       in attaching tag

    5)Opened IC in standby state must be stored in related line before production
       completed.

5] Remainder handling

    1) Opened IC & PCB must be used in 24 hrs, if it’s impossible,

      ① Store in vacuum packing with silica gel after baking within 30min

      ② After  store in dry chamber  during 24 Hours, use it

          (But, can use within unpacking 24 hours)

    2) Reel parts must be baked on low temperature(40℃)

     ※ But, MSL level 6 immediately use after unpacking within “Time on Label”

     ※Baking standards : 125℃,12~48 hrs. (Refer baking table or part maker’s recommendation)

     ※ Temperature/Humidity standard of dry chamber : 25 ± 5℃, 10%↓

   ※ Reuse process of Silica-gel

    1) Collect remaining Silica gel after open vacuum packing IC, and store it on
        guarantee place.

    2) Silica gel should bake in can see silica gel’s cover conditions.

       

- Baking Standard : 125℃, 16Hrs

      ex)  

                                                                                                                  

                

   

à Baking standards: 118℃(245℉)/16hrs

      

  

   ex)       

        - Standard of storing when baking : It should spread. No fold.

               

    3) Input dry chamber after completing Bake

    4) When vacuum packing remaining IC, It enclose silica gel in dry chamber

       - Enclosed amount : 1unit or 2unit (Obey standard of Maker)

       - If materials let out the storage, material’s quantify must have to limit according
         to used within 24hrs. (If procedure plans of same model is fixed more than a day,
         divide by 24 hours the material is exported.)  

       - Remained material immediately must have to vacuum pack with silica gel.

       - If storage with vacuum packing after proceed a materials baking, in below
         case(include silica gel)

       - Remained IC that it used in SMT line 

       - Over the 24hrs from open time

       - IC incoming  with not vacuum packing

       - Baking chamber caution

       - If  vacuum chamber are used at another IC, baking after store the dry chamber.

       - If  baking is in progress about tray, reel, silica-gel, worker have to use the
         specified temperature/time condition.

       - If baking process is impossible material about the reel components, worker
         must only vacuum packing. (Reel components have to exhaust within use-by date)

To be continued ...

SMT Process & Standards Guide

SMT Process & Standards Guide 

In this part i will share some of  our SMT Process supported with flow charts and standards ...

Note: SMT standards varies from company to another according to the manufacturing type and components 

so Let's Start...