Regarding BGA packaging, you must read this article! | DayDayNews

Introduction

BGA process has become one of the best choices for IC packaging. Up to now, there are more and more types of BGA packaging technology, different types have different characteristics, and the process flow is also different. At the same time, with the development of BGA technology and IC industry, domestic packaging and testing manufacturers have gradually stepped onto the stage of history.

In the 1990s, BGA (Ball grid array, ball grid array or solder ball array) packaging technology developed rapidly and became one of the mainstream packaging processes. It is a high-density surface mount packaging technology. At the bottom of the package, the pins are all ball-shaped and arranged in a grid-like pattern, hence the name BGA.

At present, the motherboard control chipsets mostly use this kind of packaging technology, and the material is mostly ceramic. The memory packaged with BGA technology can increase the memory capacity by two to three times without changing the size of the memory.

The main content of this article is the main classification and characteristics of BGA packaging , BGA packaging process flow , and domestic packaging and testing manufacturers .

1

BGA packaging technology classification and characteristics

BGA package types are many, according to the arrangement of solder balls can be divided into peripheral type, staggered type and full array type.

is mainly divided into PBGA (Plastic BGA,Plastic package BGA), CBGA (Ceramic BGA, ceramic BGA), FCBGA (Filpchip BGA, flip chip BGA), TBGA (Tape BGA, carrier tape BGA).

PBGA package

PBGA is the most commonly used BGA package, made of plastic materials and plastic technology. The type of substrate used is PCB substrate material (BT resin/glass laminate). After the bare chip is connected to the top of the substrate and the lead frame by bonding and WB technology, the whole is realized by injection molding (epoxy film-plastic mixture) Molding. In Intel series CPUs, Pentium II, III, IV processors all use this package.

The solder ball material is low melting point eutectic solder alloy 63Sn37Pb, the diameter is about 1mm, and the bottom of the solder ball does not need to be connected to the package body by 1.27-2.54mm. Also use solder. When assembling, the solder balls melt and join with the solder plate on the PCB surface, showing a barrel shape.

PBGA package features are mainly manifested in the following four aspects:

1. Low production cost and high cost performance.

2. The solder balls participate in the formation of reflow solder joints, and the coplanarity requirements are loose.

3. Good thermal matching with epoxy resin substrate, high quality and good performance when assembled to PCB.

4. Sensitive to moisture, PoPCorn effect is serious, reliability is hidden, and high QFP package height is also a technical challenge.

CBGA package

CBGA is formed by mounting a bare chip on the top surface of a ceramic multilayer substrate carrier,The metal cover plate is welded on the substrate with a sealing solder to protect the chip, leads and pads. The connected package is airtight, which can improve its reliability and physical protection performance. Pentium I, II, and Pentium Pro processors have all used this package.

CBGA uses a multilayer ceramic wiring substrate, the solder ball material is a high melting point 90Pb10Sn eutectic solder, and the solder ball is connected with a low-temperature eutectic solder of 63Pb10Sn and the package body. , It adopts cover + glass air seal, which belongs to the category of air seal.

CBGA package features are mainly manifested in the following six aspects:

1. It is not sensitive to moisture, has good reliability, and has good electrical and thermal properties.

2. Good matching with ceramic substrate CTE.

3. The connected chips and components can be reworked well.

4. The bare chip adopts FCB technology, and the interconnection density is higher.

5. Higher packaging cost.

6. Poor CTE matching with epoxy resin and other substrates.

FCBGA package

FCBGA is currently the most important packaging format for graphics acceleration chips . This packaging technology began in the 1960s, when IBM developed the so-called so-called for the assembly of large computers The C4 (Controlled Collapse Chip Connection) technology was then further developed to use the surface tension of the molten bump to support the weight of the chip and control the height of the bump, and it has become the development direction of flip chip technology.

This kind of package uses small balls instead of the original pins to connect to the processor. A total of 479 balls are required, and the diameters are all 0.78 mm, which can provide the shortest external connection distance. FCBGA is interconnected with the substrate through FCB technology. The difference from PBGA is that the bare chip faces down.

FCBGA package characteristics are mainly manifested in the following three aspects:

1. Excellent electrical and electromagnetic performance, and can reduce the interconnection loss between components. Problems with interference and withstand higher frequencies.

2. Increase the density of I/O, improve the efficiency of use, and effectively reduce the substrate area by 30% to 60%.

3. Good heat dissipation, which can improve the stability of the chip during high-speed operation.

TBGA package

TBGA, also known as array carrier tape automatic bonding, is a relatively novel BGA package. The type of substrate used is PI multilayer wiring substrate, the solder ball material is a high melting point solder alloy, and a low melting point solder alloy is used for soldering.

TBGA package features are mainly manifested in the following five aspects:

1. Good thermal matching with epoxy PCB substrate.

2. The thinnest BGA package form, which is conducive to chip thinning.

3. Compared with CBGA, the cost is lower.

4. Sensitive to heat and humidity.

5. The chip is light and small. Compared with other BGA types, the self-calibration deviation is large.

2

BGA packaging process flow

Currently,Many chip packages are BGA type, the biggest advantage of this type of package is to save board space. The most common structure is the chip-up structure, and the cavity-down structure is required for heat treatment.

Most packages use chip bonding technology to connect the chip and the substrate, and realize the electrical connection between the chip and the substrate. The same is true for BGA, but more often uses flip-chip interconnect technology. adopts a flip chip design to directly connect the heat sink to the chip to achieve better heat dissipation.

PBGA packaging process flow

1. Preparation of PBGA substrate

Extremely thin (12-18um thick) copper foil is pressed on both sides of the BT resin/glass core board, and then drilled And through hole metallization, the through hole is generally located around the substrate; then use the conventional PWB process (lamination, exposure, development, etching, etc.) to make patterns on both sides of the substrate (conduction strips, electrodes, and the array of solder balls for mounting ); Finally, a dielectric solder mask is formed and a pattern is made to expose the electrode and welding area.

2. Packaging process

Wafer thinning→wafer cutting→ chip bonding →cleaning→ wire bonding →cleaning→ molded package →assembly of solder balls→ reflow soldering →marking→separation→inspection And testing→Packaging

chip bonding: uses silver-filled epoxy resin adhesive (conductive glue) to bond the IC chip on the substrate plated with a thin layer of Ni-Au

wire bonding: After bonding and curing, use a gold wire ball bonder to connect the solder area on the IC chip to the Ni-Au plated solder area on the substrate with gold wires.

Molded package: uses epoxy with quartz powder Resin molding for molding encapsulation,To protect the chip, bonding wires and pads.

reflow soldering: After solidification, use a specially designed pick-up tool (automatic solder ball pick-and-place machine) to place solder balls Sn62Pb36Ag2 or Sn63Pb37 with a melting point of 183°C and a diameter of 30mil (0.75mm). On the pads, reflow soldering is carried out in a traditional reflow soldering furnace under N2 atmosphere (the maximum processing temperature does not exceed 230°C), and the solder balls are soldered to the Ni-Au-plated substrate pads.

TBGA packaging process flow

1. TBGA carrier tape production

TBGA carrier tape is made of polyimide PI material first, in the production, The two sides of the carrier tape are coated with copper, and then through holes and through holes are metalized and patterns are made; then nickel and gold are plated, and the carrier tape with metalized through holes and redistribution patterns is divided into single units.

The packaged heat sink is the solid body of the package and the core cavity substrate of the package. Therefore, the carrier tape must be bonded to the heat sink with a pressure-sensitive adhesive before packaging.

TBGA is a package form suitable for high I/O number applications. The number of I/Os can be 200-1000 . The connection of the chip can be flip-chip reflow or thermal compression bonding.

2. Packaging process

Wafer thinning → Wafer cutting → chip bonding → cleaning → wire bonding → plasma cleaning → liquid sealant potting → assembly solder ball → Reflow soldering→marking→final inspection→testing→packaging

chip bonding: full array chip,Using C4 process; peripheral gold bump chip, hot-press bonding.

Assemble the solder ball: uses micro-welding technology to solder the solder ball (10Sn90Pb) to the carrier tape, the top of the solder ball is melted into the plated through hole, and the chip is encapsulated with epoxy resin after soldering.

FCBGA packaging process flow

1.FCGBA substrate production

FCGBA substrate production is the high temperature co-firing of multilayer ceramic sheets into a multilayer ceramic metalized substrate, and then on the substrate Make multilayer metal wiring, then electroplating etc.

2. Packaging process

Wafer bump preparation → wafer dicing → chip flip-chip and reflow soldering → underfill → thermal grease and sealing solder distribution → capping → assembly of solder balls →Reflow soldering→Marking→Separation final inspection→Testing→Encapsulation

Flip-chip soldering: overcomes the problem of the limit of the center distance of the wire bond pads, and provides more improvements in the chip power/ground distribution design It is more convenient and provides a more complete signal for high-frequency and high-power devices.

substrate selection: The key factors are the material's coefficient of thermal expansion (CTE), dielectric constant, dielectric loss, resistivity and thermal conductivity.

bump technology: The commonly used bump material is gold bump, 95Pb5Sn, 90Pb10Sn solder balls (reflow temperature is about 350℃). The key to the technology is that when the pitch is reduced, the stability of the bump size must be maintained. The uniformity and coplanarity of solder bumps have a great influence on the pass rate of flip chip soldering.

CBGA packaging process flow

Compared with PBGA and TBGA,CBGA is slightly different, mainly in three aspects:

1. CBGA substrate is a multilayer ceramic wiring substrate, PBGA substrate is a BT multilayer wiring substrate, and TBGA substrate is a polyimide (PI) reinforced ring Multi-layer Cu wiring substrate.

2. The solder balls under the CBGA substrate are 90%Pb-10Sn% or 95%Pb-5Sn% high temperature solder balls, while the solder to the substrate and PWB is 37%Pb-63Sn% eutectic low temperature soldering Ball

3. The cover of CBGA is ceramic, making it a hermetic package; while PBGA and TBGA are plastic packages, not hermetic packages.

3

domestic packaging and testing manufacturers

Packaging and testing are an indispensable part of semiconductor manufacturing. The global packaging and testing market will continue to grow steadily, and the proportion of the professional foundry packaging and testing market will gradually expand.

In recent years, as the semiconductor industry has entered a mature period, the packaging and testing industry has continued to merge, and the trend of Evergrande is becoming more and more obvious. Taiwan, China is the region with the strongest professional packaging and testing capabilities. In recent years, China's packaging and testing companies have achieved rapid growth in operating income through endogenous development and extensional mergers and acquisitions, and have gradually become an important force in the global packaging and testing industry.

1. Jiangsu Changjiang Electronics Technology Co., Ltd.

official website: _strong3_p4strong.com/.com/strong2 Changjiang Electronics Technology was established in 1972 and successfully listed on the main board of the Shanghai Stock Exchange in 2003.After more than 40 years of development, Changjiang Electronics Technology has become a world-renowned integrated circuit packaging and testing company. Changjiang Electronics Technology provides global packaging design, product development and certification, as well as a full set of professional production services from chip testing, packaging to finished product testing and shipping.

Changjiang Electronics Technology is committed to a sustainable development strategy, advocating the harmonious development of employees, enterprises, customers, shareholders and society, and the concept of win-win cooperation. It has been evaluated as a national key high-tech enterprise, one of China's top 100 electronics companies, and integrated circuit packaging. The chairman unit of the strategic alliance of technological innovation, China's export product quality demonstration enterprise, etc., has a domestic high-density integrated circuit national engineering laboratory, a national-level enterprise technology center, and a post-doctoral scientific research workstation.

2. Tianshui Huatian Technology Co., Ltd.

http://.com/.com/ Company introduction: Tianshui Huatian Technology Co., Ltd. was established on December 25, 2003, and was listed on the Shenzhen Stock Exchange on November 20, 2007. Stock abbreviation: Huatian Technology; stock code: 002185. At present, the company has a total share capital of 2,131,112,900 shares and a registered capital of 2,131,112,900 yuan.

The company is mainly engaged in semiconductor integrated circuit packaging and testing business. At present, the company's integrated circuit packaging products mainly include DIP/SDIP, SOT, SOP, SSOP, TSSOP/ETSSOP, QFP/LQFP/TQFP, QFN/DFN, BGA/LGA, FC, MCM (MCP), SiP, WLP, TSV, Bumping , MEMS and other series, products are mainly used in computers, network communications, consumer electronics and smart mobile terminals, Internet of Things, industrial automation control, automotive electronics and other electronic complete machines and intelligent fields.The annual packaging scale and sales revenue of the company's integrated circuits rank second among listed companies in the same industry in my country.

3.Tongfu Microelectronics Co., Ltd.

http://www.strongt4p strong_strongp. Company introduction: Tongfu Microelectronics Co., Ltd. was established in October 1997 and listed on the Shenzhen Stock Exchange in August 2007 (stock abbreviation: Tongfu Microelectronics, stock code: 002156). The company’s total share capital is 1153.7 million shares. The largest shareholder Nantong Huada Microelectronics Group Co., Ltd. (accounting for 28.35% of the shares) and the National Integrated Circuit Industry Investment Fund Co., Ltd. will become the second largest shareholder (accounting for 21.72 shares) after the completion of the equity delivery. %), the company's total assets are more than 12 billion yuan.

Tongfu Microelectronics specializes in integrated circuit packaging and testing. It is a national key high-tech enterprise, a vice chairman unit of the China Semiconductor Industry Association, an executive vice chairman unit of the National Integrated Circuit Packaging and Testing Industry Chain Technology Innovation Alliance, and a top 100 electronic information company in China Enterprise, China's top three integrated circuit packaging and testing companies. Ranked 6th among global packaging and testing companies in 2017.

4. Jiangsu Nantong Huada Microelectronics Group Co., Ltd.

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Company introduction: Nantong Huada Microelectronics Group Co., Ltd. was founded in 1966,After more than 50 years of development, it has become a private enterprise group company with certain strength with semiconductor device packaging and testing as its main business.

The company's business involves the upstream and downstream of the industrial chain, and is at the leading domestic level in the fields of semiconductor device packaging and testing, equipment manufacturing, and molds. The company's total assets are 12.8 billion yuan, and its 2017 sales revenue reached 7.6 billion yuan. The company is one of the first batch of IC-certified enterprises in the country, and has been rated as "China's Top 100 Electronics Companies" and "China's Top Ten Packaging and Testing Companies" for many years.

5. Sichuan Mingtai Electronic Technology Co., Ltd.

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Company introduction: Sichuan Mingtai Electronic Technology Co., Ltd. was established in August 2010 to promote the development of China's integrated circuit packaging and testing industry.

The company has a total investment of 150 million yuan, a workshop area of ​​12,000 square meters, and a packaging and purification area of ​​6,000 square meters; it has brand new fully automatic packaging equipment manufactured by internationally renowned brands DISCO, K&S and ASM, and manufactured by DAGE, Shimadzu, and PVA. Testing equipment such as push-pull force gauge, X-RAY, layered scanner, etc. with international advanced level.

6. Guangdong Huaguan Semiconductor Co., Ltd.

http://www.strongp.com/strong

Introduction: Guangdong Huaguan Semiconductor Co., Ltd. was established in 2011,It is a quasi-high-tech enterprise specializing in R&D, packaging, testing and sales of semiconductor devices. HGSEMI&HGC is the independent brand of Huaguan Company.

The company has the ability to achieve an annual output value of 300 million yuan and an annual shipment of 2 billion integrated circuits. The current products include power management, operational amplifiers, audio amplifiers, interfaces and drivers, logic devices, memory, time bases and clocks, and data acquisition , MOSFT and dedicated circuits are mainly used in automotive electronics, instrumentation, security, network communications, industrial automation, LED lighting, switching power supplies, smart home appliances, gold card engineering, intelligent transportation and other fields.

7. Shenzhen Jingtong Electronics Co., Ltd.

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Company introduction: Shenzhen Jingtong Electronics Co., Ltd. is a professional semiconductor discrete device packaging enterprise. The company was established in 1994 with a registered capital of RMB 40 million. It is a collection of R&D, production, sales, and technical services. The integrated high-tech enterprise is one of the earliest enterprises engaged in the large-scale production of high back pressure, medium and high power diodes and triodes in China, and a member unit of the China Semiconductor Industry Association.

The company has 9,800 square meters of production workshops, including 1,500 square meters of 10,000-class ultra-clean workshops, with a production capacity of 4.5 million pieces per day, and the annual production and sales value has exceeded 200 million yuan for several consecutive years.

8. Peyton Technology (Shenzhen) Co., Ltd.

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Company introduction: Peyton Technology (Shenzhen) Co., Ltd. is a domestic limited liability company invested and constructed by Shenzhen Great Wall Development Technology Co., Ltd.At present, it is mainly engaged in dynamic random storage (DRAM) and flash memory (FLASH) chip packaging and testing business.

Peyton Technology provides high-quality chip packaging and testing services for the world's large DRAM and FLASH manufacturers. The company has a registered capital of 248.3 million yuan and a total investment of 100 million U.S. dollars; since its establishment in July 2004, as of December 2015, it has completed a total of approximately 1 billion yuan in fixed assets investment.

9. Shennan Circuit Co., Ltd.

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. Company introduction: Shennan Circuits Co., Ltd. was established in 1984 with a registered capital of 280 million yuan. Its headquarter is located in Shenzhen, Guangdong Province, China. Its main production bases are located in Shenzhen, Jiangsu, Wuxi and Nantong. It has technical support and support in North America. Sales and service center, with R&D sites in Europe.

The company has three businesses of printed circuit boards, packaging substrates and electronic assembly, forming a unique "3-In-One" business layout in the industry: that is, with interconnection as the core, it is constantly strengthening its leading position in the printed circuit board business At the same time, we will vigorously develop the packaging substrate business with the "same root of technology" and the electronic assembly business with the "same source of customers". The company has the comprehensive manufacturing capabilities of "samples→medium and small batches→large batches", and provides customers with professional and efficient one-stop integrated solutions through the development of full value chain services such as program design, manufacturing, electronic assembly, micro-assembly and testing. .

10. Shenzhen Biwei Storage Technology Co., Ltd.

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Company introduction: Shenzhen Baiwei Storage Technology Co., Ltd. was established in 1995,Focus on miniaturization of storage and electronic products. BIWIN integrates R&D, production, sales and service to provide customers with comprehensive storage solutions and packaging and testing services. Products and services include SSDs, embedded memory chips, SIP modules, and packaging and testing services. As a leading domestic packaging and testing OEM/ODM supplier, we provide customized packaging and testing services for industry partners.

11.Shenzhen Sigrid Semiconductor Technology Co., Ltd.

official website: http://www.strong.strong.com/.com/ html

Company introduction: Shenzhen Sige Semiconductor Technology Co., Ltd., established in 1997, is a modern national high-tech enterprise specializing in integrated circuit chip packaging, R&D and production. Since its establishment, the company has been committed to the development of chip packaging and testing industries such as LED driver integrated circuits, power supplies, communications, storage, and photosensitive integrated circuits.

12. Suzhou Jingfang Semiconductor Technology Co., Ltd.

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Company introduction: Suzhou Jingfang Semiconductor Technology Co., Ltd. (SSE: 603005) was established in Suzhou in June 2005.It is a company dedicated to the development and innovation of new technologies to provide customers with reliable, miniaturized, high-performance and cost-effective semiconductor packaging mass production service providers.

In the past ten years, Jingfang Technology has become a leader in technology development and innovation, and providing high-quality mass production services. As the company continues to grow, it has established a subsidiary Optiz Inc. in the United States.

13. Shanghai Xinzhe Microelectronics Technology Co., Ltd.

http://www.simstrong.com .com: sh.com/

Company introduction: Shanghai Xinzhe Microelectronics Technology Co., Ltd. was established in June 2007. It is a company engaged in integrated circuit research and development, design, processing, manufacturing and for domestic and foreign chip design companies, wafer manufacturing A high-tech enterprise that provides one-stop technical services for packaging and testing.

Its products are mainly used in automotive electronics, medical electronics, smart phones, tablet computers, green energy, LED drivers, silicon microphones and other electronic and electrical equipment. More than 50% of the products produced are exported to overseas electronic markets. It is currently the world's largest optical mouse control chip packaging company.

14. ASE Group

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official website: http://ch/strong_strongp

. ASE Group was established in 1984,The founders are brothers Zhang Qiansheng and Zhang Hongben. It was listed on the Taiwan Stock Exchange in 1989 and listed in the United States in 2000. Its subsidiary, ASE Test Limited, was listed on the US NASDAQ in 1996 and Taiwan in 1998.

ASE Group is one of the world's largest semiconductor manufacturing service companies, providing the best service and the most advanced technology to customers around the world for a long time. Since its establishment in 1984, it has focused on providing complete packaging and testing services for semiconductor customers, including integrated services from chip front-end testing and wafer probe testing to back-end packaging, material and finished product testing.

15. Powertech

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Company introduction: was established in 1997 and is a Taiwan stock listed company (stock code: 6239). It is a professional memory IC packaging and testing company, and it ranks among the global integrated circuit packaging and testing service providers. leadership.

's service scope covers wafer probing, packaging, testing, pre-burning to global shipment of finished products. At present, Powertech Technology has more than 15,000 employees and several world-class factories located in Hsinchu and Zhunan in Taiwan, Suzhou, Xi'an, Singapore and Japan in China, all over the world.

16.King Yuan Electronics Co., Ltd.

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Company introduction: Jingyuan Electronics Co., Ltd. was established in May 1987,At present, it has become the largest professional testing company in the division of labor in the upstream and downstream design, manufacturing, packaging, and testing industries of the global semiconductor industry. The head office is located beside Gongdao Fifth Road, Hsinchu City, and the production base is located in Zhunan Township, Miaoli County.

In the back-end process of semiconductor manufacturing, KYEC's service areas include wafer probing (approximately 45%), IC product testing (approximately 46%), and wafer grinding/cutting/die picking (approximately 9%). %)Wait. The product line covers Memory, Logic&Mixed-Signal, SOC, CIS/CCD, LCD Driver, RF/Wireless, and the total number of test machines exceeds 2000. In terms of the main customer groups, fabless factories accounted for about 73%, foundry factories accounted for about 3% weak, and the remaining IDM factories accounted for about 24%.

17. Nanmao Technology Co., Ltd.

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Company introduction: Nanmao Technology was established in August 1997 and listed on the Taiwan Stock Exchange in April 2014 (stock code: 8150). Its parent company, Bermuda Nanmao Technology, was established in June 2001 Listed on the NASDAQ stock market in the United States (stock code: IMOS), and its clients include semiconductor design companies, integrated component manufacturing companies and semiconductor wafer fabs.

Nanmao Technology's main business is to provide high-density, high-level memory products, packaging, testing, and related post-processing and distribution services for logic products and mixed-signal products. After the overall body circuit packaging and testing provided by Nanmao, the customer's products can be smoothly applied to products in related industries such as information, communications, office automation, and consumer electronics.

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