reflower.ppt

1、,Lead-less Soldering Process With 0201,What has been done to introduce Lead-less Soldering Process and 0201 Placement.?,Expected conditions to check,What is Lead-less solder? What is its ingredient and its characteristic? With Screen Printer. What is the difference from Eutectic? How about the mater

2、ial of stencil and the shape of its Opening With Chip Mounter. What is the required accuracy? How about the nozzles? With Reflow Oven. What is the required profile? How about the structure?,Assign one division to be in charge, for the entire company. call all the Solder Paste maker, then obtain the

3、solder paste available at that point in time Solderability Strength of Soldering joint Printability Tackkingability investigation of Patent 3-elements-alloy(Sn/3.0Ag/0.5Cu) other company already obtained 4-elements-alloy(Sn/2.5Ag/1Bi/0.5Cu) no company obtained,Selection of Lead-less Solder paste,） c

4、ommon characteristic of lead-less solder,High melting point temperature Poor quality of wetting spread Slightly better strength of solder joint Narrow range for the condition of use Specific gravity is lighter but Specific heat is higher Material cost is higher (11.3 times of eutectic solder ),Featu

5、res of Lead-free Solder,2) Features by composition,Finally, Sony selected Sn/3.0Ag/0.5Cu. To synchronize with the main stream of the industry for price can get the better price for supply several supplier can supply Solderability (compare with Sn-Pb eutectic solder) Self-Alignment function may be dr

6、opped Improve the Mount accuracy 0.10 0.06 Wettability may be dropped（around 80% of Sn/Pb eutactic solder） amount of solder some parts may need to increase size of land same size shall be OK shape of land same shape shall be OK Polarity of the parts no need to change OCB surface treatment no need to

7、 change Condition for the Production for Screen Printer improve and maintain the printing accuracy for Mounter improve and maintain the mounting accuracy for Reflow Oven selection of the most suitable reflow oven,Lead-Less Solders,Japanese Electrical Maker using,Sn-2.5Ag-1Bi-0.5Cu Sn-3Ag-0.5Cu Sn-0.

8、7Cu Sn-3.5Ag-0.5Cu-Ni-Ge Sn-2.8Ag-1Bi-0.5Cu Sn-3.5Ag-0.7Cu Sn-8Zn-3Bi Not Fixed,Status&Plan of Japanese Electrical maker,History of Chip size change at Sony,0201,0402,Start lead-less,Mounter,Reflow Oven,C/V,IN,OUT,Printing Inspection Machine,Improvement and maintenance of mount position accuracy,* I

9、mprovement of parts recognition accuracy,- To purchase high heat resistance components - To check the heat resistance temperature of the components - To use lead-free lead materials, Selection of proper heating temperature,Set proper conditions. Maintain the proper conditions., Selection and use of

10、proper reflow furnace,Unmelted, etc.,Damage to components,To train operators,To collect relevant information,Components,Offset,Standing,Outline of the reflow soldering application & 0201Chip Mounting system using lead-free solder,Bridge,Characteristic of lead-free solder compared with Sn-Pb eutectic

11、 solder,Cold soldering,To communicate with material makers for boards, solder, and parts,Printer,- Poor wettability - Less self-alignment effect - Higher soldering temperature,* Perform correct measurement, * Create correct test board, etc.,Improvement and maintenance of P/C accuracy, etc.,Selection

12、 of lead-free solder Storage and control of lead-free solder Recheck of the macro (screen),Offset,Standing,Bridge,Cold soldering,C/V,Screen Printer(1),The difference from Sn-Pb solder may no change for Printability Tackkingability may be weaker may need to change for 0201 Chip,Change point for 0201C

13、hip particle diameter :4050m 2535m *need to change according to the solder amount required squeegee : should be Metal *modify some of Screen printer thickness of stencil ：100130m *related to PCB : adopt only Aditive method *should control the solder amount *printability,Screen Printer(1),Pad on PCB

14、and opening size on the stencil, Mount Accuracy as a minimum of 60m required, from the current standard level of 100m need high accuracy as the self alignment is not effective Control for the placement height the amount to push on the solder should be less than 100m as the thickness of the solder ma

15、y be 95 135m, the solder paste would be spread out from the land if the push amount is too much order of placement should mount from the thinner components nozzle may interfere the higher components in case of narrow pitch Timing of Vacuum change shorten the time on the nozzle for pick-up and placem

16、ent it would affect to the placement accuracy and pick-up rate if the response of vacuum change is slow,Required condition to Chip Mounter for 0201 chip with lead-less solder,Eutectic, lower melting point, Placement accuracy,Soldering N/G may frequently occur if the placement accuracy is over 60m,pl

17、acement,Lead-less Self-alignment is ineffective,After Reflow, Control of placement height,Soldering N/G may occur frequently, if no control for the placement height the solder paste spread out from the land could be the cause of soldering N/G, as the surface tension is less than eutectic solder., Or

18、der of Placement,To avoid the interference to the component and to avoid the shift, it is required to place from the thinner components.,Resistor,Resistor,Capacitor,Resistor,Nozzle,Mechanical Valve,Short distance,Pick-up and Placement movement,Keep the reliability of Accuracy by speed-up the respons

19、e time of Vacuum-changeover,Vacuum Point,Up,Mount point,Down,t,t,Vacuum pressure,Nozzle position,Reflow(1),Temperature of the Reflow will be higher by introducing Lead-less solder Reconsider the Profile Management standard not only the Temperature setting, but also minimize the variation range. Peak

20、（Peak within 10） Reconsider the Reflow-oven itself accuracy against the peak temperature avoid the damage on components,Reconsider the Reflow Management,Setting range of Temp profile,Temperature distribution model for the temperature profile at the reflow section, Approximate soldering temperature f

21、or several composition types of lead-free solder ,Temperature on the surface of the component,Section where it is easy for the temperature to rise,Section where it is difficult for the temperature to rise,180,190,200,210,220,230,240,250,(C),Soldering temperature,183C,221 C,227C,217C,215 222C,199,245 C,210C kept for several seconds,130180 ，,Peak temperature: 240C or less,60120 ,6090 ,130160 ，,Less than 30,1. Two or more reflow zones required,2. Temperature uniformity performance,The value t