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CSR

CORPORATE SOCIAL RESPONSIBILITY친환경기술

Whisker

The Relation between Whisker and Stress

The Relation between Whisker and Stress. 다음 내용 참조
WhiskerRecrystallization ← From 0 to 25C (Deposit Design)
Whisker ← Mechanical Compression Stress ← Heat Changing, Bending Strress - Component Design
Whisker ← Oxidation ← Humidity
Whisker ← Diffusion ← Heat, Substrate and Base Materials
Whisker ← Internal Stress ← Heat
Substrate. 다음 내용 참조
Substrate : Whisker, Sn Oxide, Sn Layer, IMC, Sn Grain, Boundaries

Tin Whiskers Examples

Tin Whiskers Examples. 다음 내용 참조
Hybrid Package Lid, Relay Terminals, Test Points, SMT Fuses, Terminal Lugs...

100배 확대한 사진을 다시 부위별로 250배 확대해서 대조해 보았다

Examples of whiskers observed on QFPs after constant temperature aging

Examples of whiskers observed on QFPs after constant temperature aging. 다음 내용 참조
일정한 온도로 가열한 이후 관찰한 QFP의 예는 10㎛당 각각 Pure Tin -55g℃, Sn/Bi -55g℃, Sn/Bi -Room의 모습으로 관찰된다

Summary of room temperature aging results

Summary of room temperature aging results Sn, Sn - 3% Bi, Sn - 3% Bi, Sn - 10% Pb의 Plating, Room temp. age, Not assembled, Assembled with SAC or Sn-Pb를 나타낸 표입니다
Plating Room temp. age Not assembled Assembled with SAC or Sn-Pb
Sn 6 months >15㎛ whiskers  
Sn 8 months   No whiskers(bumps)
Sn - 3% Bi 6 months 0 -15㎛ whiskers  
Sn - 3% Bi 8 months   No whiskers
Sn - 10% PB 8 months   No whiskers

I.R reflow profile

I.R reflow profile. 다음 내용 참조
그래프사진 설명 : 시간과 온도 상승에 비례하여 Ramp-up과 Critical Zone은 같이 상승하는데 ts Preheat구간부터 t25℃ to Peak구간까지는 정점을 찍는데 최고 상승 구간을 Ramp-up, 하강 구간을 Critical Zone이라고 칭해 최고 상승 구간인 tp까지 도달한다.
I.R reflow profile Profile Feature, Lead-Free Product를 나타낸 표입니다
Profile Feature Lead-Free Product
Average ramp-up rate 3℃/second max.
Preheat 150~200℃ ; 60~180seconds
Time maintained above 217℃ ; 60~150seconds
Peak Temperature 255~260℃ ; 10~20seconds
Ramp-down rate 6℃/second max.
Time 25℃ to Peak Temperature 8 minutes max.

Lead Free

TSOP Lead Plating : Sn/Pb → Sn/Bi
FBGA Solder Ball : Sn/Pb → Sn/Ag/Cu
Module Solder Paste : Sn/Pb → Sn/Ag/Cu

Halogen Free

  • TSOP Package : EMC
  • FBGA Package : EMC, Subctrate
  • Module : PCB
  • Usage : Used as flame retardant in EMC & PCB as resin
  • Method : substitute to Nitrogen material P,N and increase filler quantity
  • Brominated Flame Retardant with Sb2O3    Flame Retarding Resin + High Filler Loading
  • Halogen Free

EMC

EMC Chemical Name of Flame Retardant, CAS No.를 나타낸 표입니다.
Chemical Name of Flame Retardant CAS No.
Formaldehyde Polymer with Bromophenol and Chloromethyl 68541-56-0
Antimony trioxide 1309-64-4

Package Substrate & Module PCB

Package Substrate & Module PCB Chemical Name of Flame Retardant, CAS No.를 나타낸 표입니다.
Chemical Name of Flame Retardant CAS No.
Epoxy Resin 26265-8-7