BGA is the abbreviation of Ball Grid Array. This, in a general form, is an array of small sized / tiny metallic conductor balls that are arranged in a harmonies form on the Board that we proceed towards making a PCB. Nowadays; due to increased demand of only BGAs, companies (manufacturers) has formed (Example- Xilinx).
These balls are eventually used to making connections using small and precise soldering while putting microprocessors and integrated circuits; in order to make the complete circuit that we intend to make / work out for. The process of connecting the small balls is called SMT ( Surface Mount Technology) .
Reason of BGA being so popular in modern technology:
There is a bunch of reasons why modern technology depends on BGA on a great extent. The most important one is that, BGA has superlative thermal dissipation capability, making the core to be cool while in operation; hence prolonging the products lifetime. Heat is the most important measure to deal with and BGA is the reason why tech products work so smooth while being normal in temperature while working at even full load. Second most important reason is the electrical properties. The shortest distance connections with lower possible resistive ways make the purpose of using BGAs even more valuable and worthy. Third most important reason is Compatibility. Being able to use the smallest space while working with greater number of balls allows the manufacturer to place more and more workable options in the product that makes it even more valuable and of value. This is indirectly related to lower production cost while making valuable and better priced products for the production and market customers.
Types of BGA:
There are different types of BGA that are being used in most of the countries by most of the manufacturers but the most popular ones and widely used ones are detailed below with a short description to each-
PBGA (Plastic Ball Grid Array):
PBGA is the abbreviation of Plastic Ball Grid Array. This is the most popular type for double-sided PCBs that are being used recently. It was first invented by the company MOTOROLA and is now being used widely by most of the manufacturers. The core is of bismaleimide triazine (BT) resin that is used as the substrate material. This along with the application of over molded pad array carrier (OMPAC) sealant tech or glob to pad array carrier (GTPAC) is highly reliable and is verified by JEDEC (Level 3). Such BGAs carry starting from 200 to about 500 ball arrays, which is really good for a good number of applications to put on!
CBGA (Ceramic Ball Grid Array):
As the name implies, this is Ceramic type BGA. The ration between tin and lead is 10:90 in this type. Having a very high melting point, this type BGA requires C4 Approach (Controlled Collapse Chip Connection) for making the bridge between BGAs and PCBs. The cost is a little high than that of PBGAs but this type BGA is extremely reliable for better electrical performance and better thermal conductivity.
TBGA (Tape Ball Grid Array):
The only disadvantage of TBGA is that this always costs higher than PBGA but if its about making thin products that should have strong core materials with better heat dissipation and superlative electrical connectivity properties, definitely TBGA is the one to select. Whether the ICs / Chips has to be faced up / down; this is the approach for making products worth while keeping the cost optimum. If chips are facing up wire bond is recommended and when chips are facing down flip chip approach is recommended in this type of BGA.
EBGA (Enhanced Ball Grid Array):
Enhanced Ball Grid Array is the summation of PBGA & additional heat sink options. Around the components/ chips on the substrate, a dam is built on its boundaries and then the liquid compounds are added to seal the components on it. In this type, chips are always faced down & wire bond is used for conduction between PCB & Chips used.
FC-BGA (Flip Chip Ball Grid Array):
This is absolute similar to CBGA while the only change in it is the ceramic substrate. Instead, BT resin is used in this FC-BGA. This way, the additional cost is saved in this type. The main value lies in the shorter electrical pathways than any other BGA types; hence better electrical conductivity and faster performance. Tin & Lead ration in this BGA type is 63:37. Another advantage in such BGA type is that, chips used on the substrate can be realigned to correct position without flip-chip alignment machine approach.
MBGA (Metal Ball Grid Array):
In this type, metal ceramic is used as the substrate. Chips are faced down in this approach and circuits are made up of sputtering coating in this type. Wire bonding is what is used to make connections in this approach. This array is very good for very good electrical performance as well as better thermal heat dissipation values.
Tessera is the name of the company that has invented Micro BGA. In this approach, chips are always faced down while the substrates are made up of packaging tape. The value lies in the use of elastomer between the tape and the chip that helps to thermal expansion stress. The most important value of Micro BGA is that they are as named, mini sized. Therefore, allowing manufacturers to plan for high tech yet small sized products. On top of that, this type is the core of higher storage products while the numbers of pins are low. Therefore, better accessibility while lower liability.
Need regarding BGAs?
BGAs are the core of the products you want to make. Not only this depends on the type of products you want to make but also you have to deal with the total production cost, weight of the final product, quality of the product while quantity of heat generated and a lot of other things. Comparing all these all at once and helping in sourcing the best-studied type we will help you to get the best pick for your purpose.
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