Q & A

BGA definition

BGA: Abbreviation of Ball Grid Array, Chinese name: Ball grid array package device

BGA package classification

PBGA-Plastic package
CBGA-Ceramic package
TBGA-Carrier tape package

BGA storage environment: 20-25 ° C, <10% RH
CSP: Chip Scale Package or μBGA-chip size package
QFP: four-sided flat package. Package pitch: 0.3mm 0.4mm

BGA rework station knowledge

Preheating definition: Preheating is to heat the entire assembly to a temperature below the melting point of the solder and reflow soldering.
The benefits of preheating: activation of flux, removal of oxides and surface films of the metal to be welded and volatiles of the flux itself, enhancing the wetting effect, reducing the temperature difference between the upper and lower PCBs, preventing thermal damage, removing moisture, and preventing popcorn To reduce the temperature difference.
Preheating method: put the PCB into the incubator for 8 to 20 hours, the temperature is set at 80 to 100 ℃ (according to the size of the PCB)
"Popcorn": refers to the moisture existing inside an integrated circuit or SMD device during the repair Rapid heat in the middle causes the moisture to expand and micro-cracking. Thermal damage includes: pad lead warpage; substrate delamination, white spots, blistering or discoloration. "Stealth" problems such as internal warpage of the substrate and attenuation of its circuit components are caused by different expansion coefficients of different materials.
Three methods for preheating the PCB before or during repair:
Oven: can bake out the moisture inside the BGA to prevent popcorn and other phenomena.
Hot plate: the residual heat in the hot plate hinders the cooling speed of the solder joint, resulting in lead Precipitation, forming a pool of lead liquid, which reduces and deteriorates the strength of the solder joint, so this method is not used.
Hot air slot: Regardless of the shape and bottom structure of the PCB assembly, the hot air can quickly and directly enter all corners and cracks of the PCB assembly, so that the PCB is heated evenly and the heating time is shortened.

SMT terminology

SMT: surface mount technology
AI: Auto-Insertion
AQL: acceptable quality level
ATE: automatic test equipment automatic test equipment
ATM: atmospheric pressure
BGA: ball grid array spherical matrix
CCD: charge coupled device monitoring connection components ( (Camera)
CLCC: Ceramic leadless chip carrier
COB: chip-on-board chip directly attached to the circuit board
cps: centipoises (viscosity unit) 1%
CSB: chip scale ball grid array chip size BGA
CSP : chip scale package
CTE: coefficient of thermal expansion
DIP: dual in-line package DIP: dual in-line package (generally refers to hand-inserted components)
FPT: fine pitch technology micro-pitch technology
FR-4: flame-retardant substrate glass Fiber film (using 硌 u as PCB material)
IC: integrate circuit integrated circuit
IR: infra-red infrared
Kpa: kilopascals (pressure unit)
LCC: leadless chip carrier
MCM: multi-chip module multi-layer chip module
MELF: metal electrode face diode
MQFP: metalized QFP metal quad flat package
NEPCON: National Electronic Package and
Production Conference International Electronic Packaging and Production Conference
PBGA lastic ball grid array plastic ball matrix
PCB rinted circuit board
PFC olymer flip chip
PLCC lastic leadless chip carrier
ppm arts per million refers to PAD (point) per million How many bad PAD (points)
psi ounds / inch 2 lbs / inch 2
PWB rinted wiring board
QFP: quad flat package
SIP: single in-line package
SIR: surface insulation resistance
SMC: Surface Mount Component Surface-mounted components
SMD: Surface Mount Device
SMEMA: Surface Mount Equipment
Manufacturers Association
SMT: surface mount technology
SOIC: small outline integrated circuit
SOJ: small out-line j-leaded package
SOP: small out-line package
SOT: small outline transistor
SPC: statistical process control
SSOP: shrink small outline package shrink small outline package
TAB: tape automaticed bonding
TCE: thermal coefficient of expansion expansion (due to heat) Coefficient
Tg: glass transition temperature
THD: Through hole device
TQFP: tape quad flat package ribbon quad flat package
UV: ultraviolet ultraviolet
uBGA: micro BGA micro ball matrix
cBGA: ceramic BGA ceramic ball matrix
PTH: Plated Thru Hole Via hole
MESH Mesh
OXIDE Oxide
FLUX flux
LGA (Land Grid Arry) packaging technology LGA package does not require ball implantation, suitable for light, thin and short product applications.
The TCP (Tape Carrier the Package)
Solder mask solder mask
Soldering Iron iron
Solder balls solder balls
Solder Splash dross
Solder Skips leakage welding
Through hole through holes
Touch up welding
Briding Jiao connection (short circuit)
Solder the Wires solder wire
Solder Bars tin bars
Transter Pressure Transfer pressure (printing)
Screen Printing
Solder Powder Solder Powder
Viscosity Viscosity
Solderability
Applicability
Flip chip Flip chip
Depaneling Machine Assembly circuit board cutting machine
Solder Recovery System Tin material recovery and reuse system
Wire Welder
X-Ray Multi-layer Inspection System X-Ray Multi-layer Inspection System
BGA Open / Short X-Ray Inspection Machine BGA X-Ray Inspection Machine
Prepreg Copper Foil Sheeter PP Copper Foil Cutting Machine
Flex Circuit Connections Soft cable welding machine
LCD Rework Station LCD repair machine
Battery Electro Welder Battery electrode welding machine
PCMCIA Card Welder PCMCIA card connector welding
Laser Diode Semiconductor laser
Ion Lasers Ion laser
Nd: YAG Laser Garnet laser
DPSS Lasers Semiconductor Excited solid-state laser
Ultrafast Laser System
MLCC Equipment Multilayer component production equipment
Green Tape Caster, Coater thin tape forming machine
ISO Static Laminator Multilayer component equalizer
Green Tape Cutter component cutting machine
Chip Terminator Multilayer component end silver Machine
MLCC Tester Multilayer Capacitance Tester
Components Vision Inspection System Core 1 Piece Appearance Inspection Machine
Capacitor Life Test with Leakage Current Capacitor Life Test with Leakage Current
Chip
Mounting Equipment Surface Mounting Equipment Surface Mounting Equipment
Resistance Silver Electrode Coating Machine
TFT-LCD (Thin Film Transistor Liquid Crystal Display) Notebook
STN- LCD (Small and Medium-sized Ultra-twisted Liquid Crystal Display
PDA (Personal Digital Assistant)
CMP (Chemical Mechanical Polishing) Process
for Mobile Phones Slurry,
Compact Flash Memory Card (referred to as CF Memory Card) MP3, PDA, Digital Camera
Dataplay Disk (Micro CD).
Exchangeable power supply (SPS)
professional electronic manufacturing service (EMS),
PCB
high-density connection board (HDI board, refers to line width / line distance less than 4/4 mil) micro-via board (Micro-via board ),
Puddle Effect (Puddle Effect) of 5-6 mils or less : early large-area etched silver through-hole (STH) copper through-hole (CTH)
assembled circuit board cutting machine Depaneling Machine
NONCFC = CFC-free .
support PIN support column =
FM = 4 points optical
coated with chemicals to make the PCB copper pad on the bare comparison will not rust ENTEK
QFD: quality function development
PMT: product maturity test
ORT: continuous life test
FMEA: failure mode and effect analysis
TFT-LCD (Liquid-Crystal Displays Addressed by Thin-Film Transistors)
lead frame (Lead Frame ): Discrete Lead Frame (Discrete Lead Frame) and Integrated Line Lead Frame (IC Lead Frame)
The full name of the two ISPs is Internet Service Provider, which refers to the provision of Internet services
ADSL is an asymmetric digital subscriber loop modem
SOP: Standard Operation Procedure (
Wire Bonding)
Tape Automated Bonding (TAB)
Flip Chip
Quality Specification:
JIS Japanese Industrial Standard
ISO International Certification
MSDS International Material Safety Data
FLUX SIR humidified insulation resistance value
RMA (Return Material Authorization) repair operation
means repair and analysis of defective products that have problems after customer's reaction after the product is sold.
Automatic optical inspection (AOI automatic optical inspection)

BGA rework, easily become a master

With the rapid development of the electronics industry, the increasing popularity of BGA chip applications has spawned the rapid expansion of the BGA rework market. A few years ago, due to the dominance of foreign brands, the BGA rework technology appeared highly mysterious, and the rework equipment was also very expensive One hundred thousand yuan seriously hampered the popularization and promotion of BGA rework technology. With the rise of local BGA rework equipment manufacturers, today's BGA rework equipment has flew from international manufacturers to ordinary people's homes, and ordinary electronic repair enthusiasts can easily invest in, purchase the appropriate rework equipment, and start their first venture in life .
The operator can become a BGA rework master after short-term remote technical training from the manufacturer. It brings great convenience to users and benefits consumers of electronic products. A few excellent manufacturers have also gone abroad to sell Chinese products all over the world.
The current rework stations have built-in massive welding curves, and can update the database in time according to product changes, so that ordinary operators can easily skip complex and lengthy process parameter settings, as long as they can correctly select the appropriate temperature curve. Saves a lot of energy and is easier to succeed.
The current rework stations have built-in massive welding curves, and can update the database in time according to product changes, so that ordinary operators can easily skip complex and lengthy process parameter settings, as long as they can correctly select the appropriate temperature curve. Saves a lot of energy and is easier to succeed.
1. Baking:
Remove the moisture of PCB and BGA, so as to avoid welding failure due to vaporization of moisture during heating and soldering, or even damage the chip. The specific baking time is related to the sensitivity level of the chip. Generally, it is dried at 80 ℃ for about 20 hours. Ordinary drying oven can be used for the baking box, and many individual repairers use disinfection cupboards to modify, which can also achieve a good drying effect.
2.
Identify lead and lead-free: confirm by observing the appearance of the solder and the identification of the chip. When it is determined, it can be distinguished by the direct heating test of the soldering iron. Leaded 183 ℃, lead-free 217 ℃, leaded fluidity is good, lead-free fluidity is poor, from the appearance, leaded light is consistent, bright, lead-free light is inconsistent, pale.
3. BGA desoldering:
Call the appropriate temperature curve on the rework station to heat up, and after melting, remove the BGA with a vacuum suction pen.
4. Replanting the ball: Replant the ball
with a replanting tool, and clean the BGA and PCB pads with a soldering iron and a tin wire. If the BGA is not damaged, it can be reused. If it is damaged, the BGA chip needs to be replaced. Note that the solder ball must be stored in a clean and dry environment. Do not touch it with your hands or other objects to prevent the solder ball from being deformed or contaminated with grease. Unopened solder balls can be stored for one year and solder paste for half a year.
5. Replant ball welding:
call the appropriate replant ball welding curve on the rework station, and solder the solder ball on the BGA pad.
Before mounting, carefully check whether the solder mask (green oil) on the PCB pad is intact, and then lightly brush a layer of solder paste on the PCB pad with a brush, or silk-screen the solder paste on the PCB pad, and then use The manual or rework station alignment function affixes the BGA to the PCB. When the BGA is manually mounted, such as when the pitch of the solder balls is small, you need to have more skilled operation experience.
7. Reflow:
Select the appropriate hot air nozzle and call the appropriate temperature curve to solder the BGA to the PCB. The process monitoring camera can clearly observe the secondary deposition process of solder.
8. Test:
Those with conditions can use X-ray equipment to check the welding quality, or directly perform functional tests, and if they pass, they will be repaired.