Complete process of Electronic Manufacturing Services (EMS)
If you work in the procurement of electronic products (whether it’s sourcing PCBs/PCBAs or enclosures), you’ve undoubtedly heard of “EMS.” EMS, or Electronic Manufacturing Services, is a potential partner because they handle the production of printed circuit boards used in your devices, as well as the manufacturing and final assembly of related components. Furthermore, this one-stop service can power a wide range of electronic products you plan to sell. To ensure you understand the basic processes of this service and that the electronic products you plan to sell function properly, we’ll explore the fundamental processes of EMS services and other relevant information, allowing you to quickly identify a suitable partner when searching for a suitable electronic manufacturing services provider.
What are electronic manufacturing services and their business models?
Electronic manufacturing services (EMS) refer to services provided to electronic brand owners, encompassing one or more aspects beyond brand sales, including electronic product design, engineering development, raw material procurement and management, manufacturing, testing, and after-sales service. EMS is also known as electronic EMS or electronic contract manufacturing. EMS providers are companies that offer electronic products and services to original equipment manufacturers (OEMs) and end users. Furthermore, the electronic manufacturing services industry can be defined narrowly or broadly. In a narrow sense, it refers to the industry that specifically provides services for electronic products; it can also be described as the industry that outsources the manufacturing process. In a broad sense, electronic manufacturing services include a series of processes such as design, development, manufacturing, procurement, logistics, and after-sales service. Nowadays, many EMS manufacturers not only provide design, development, and material procurement for electronic products, but also offer comprehensive brand services such as raw material management, manufacturing, testing, and after-sales service.
Why is an EMS factory so important to your product?
Before delving into the basic manufacturing process of EMS, let’s understand why EMS factories are a godsend for businesses that need to source electronic products. As mentioned earlier, EMS factories ensure the integrity and functionality of your electronic devices by providing the necessary parts, such as components and printed circuits. However, this advantage is just the tip of the iceberg, as they offer additional benefits to your electronic products. These additional benefits include testing components to detect early defects, logistics and shipping to ensure timely arrival, and finally, the ability to offer returns and repair services if components they manufacture arrive at your factory with unexpected defects.
Furthermore, under the EMS production model, service providers are customer-demand oriented, offering customized electronic product manufacturing services. These services cover all stages of electronic product manufacturing, including early-stage process development, raw material procurement, new product introduction (NPI), PCBA, finished product assembly, warehousing, and logistics. Because the manufacturing of these products relies heavily on high-precision automated production equipment, it is the sub-sector within the manufacturing industry that best embodies the concepts and technologies of intelligent manufacturing. Intelligent manufacturing equipment is the core of the EMS industry’s competitiveness, directly impacting the efficiency and effectiveness of electronic product manufacturing. The upgrading and transformation of EMS manufacturers’ production equipment, especially the research, procurement, debugging, and maintenance of key equipment, represents their hard power, while production organization and management, a stable supply chain, and financial capabilities constitute their soft power.
the electronic manufacturing services process
The electronics manufacturing process consists of many manufacturing steps . Below are 12 basic stages summarized by the Geyuan Electronics team for procurement and engineers around the world to refer to.
Phase 1: PCB File Inspection
PCB document inspection is an essential step in the PCB electronics manufacturing process. It involves verifying that all elements of the PCB have been properly created and placed according to the PCB design to ensure it meets customer requirements. PCB document inspection also ensures that errors or omissions are detected before production begins, thus avoiding costly delays or rework. Therefore, manufacturers can guarantee quality control throughout the entire EMS process through thorough PCB document inspection.
Phase Two: BOM List Review
Bill of Materials (BOM) review is an essential step in the EMS process. It ensures that all components used in the product are present, documented, and suitable for their intended use. BOM review also helps identify discrepancies between the ordered items and those delivered to the production line. By thoroughly reviewing the BOM before assembly begins, manufacturers can ensure their products are made with high-quality components and materials. Without reviewing the BOM, it’s impossible to produce higher-quality finished products with fewer defects or problems.
Phase 3: PCB Manufacturing
PCB manufacturing is the electronic manufacturing process of producing printed circuit boards (PCBs). PCBs can be manufactured using different materials and technologies, depending on their intended use. Manufacturing begins with designing a PCB layout that conforms to the device specifications. Once the design is complete, it must be manufactured to create the actual circuit board. Manufacturing steps include etching copper onto a substrate such as fiberglass or ceramic, drilling holes for components and connectors, and then soldering the components onto the circuit board. After these steps are completed, the PCB must be tested to ensure its functionality before it can be sent for use in the intended device. PCB manufacturing is a complex but essential electronic manufacturing process that must be performed precisely to ensure the PCB functions as intended.
Phase 4: Procurement of Electronic Components
Electronic component procurement refers to the sourcing and supply of electronic components, such as semiconductors, resistors, and capacitors, for use in electronic devices. It involves researching suppliers who offer high-quality products at competitive prices, negotiating pricing and delivery terms, and ensuring components comply with safety regulations. As electronic products become increasingly complex, electronic component procurement has become an integral part of the EMS (Electronic Manufacturing Services) process. By outsourcing this task to experts who understand the complexities of electronic component procurement, businesses can ensure reliable supplies at reasonable costs. Furthermore, electronic component procurement professionals can provide valuable insights into the latest trends in electronic components and help ensure that any new electronic designs comply with relevant safety regulations. Ultimately, electronic component procurement enables businesses to obtain the components they need at prices appropriate to their budget when required.
Phase 5: PCB Assembly ( Three PCB Assembly Methods )
This stage mainly involves assembling electronic components onto the PCB. Different assembly methods are typically used depending on the PCB design. Generally, the following three assembly methods are commonly used.
SMT assembly
SMT assembly, or surface mount technology assembly, is an electronic manufacturing process involving the placement of components onto a printed circuit board (PCB). SMT has become one of the most widely used methods in modern electronics production due to its low cost and high efficiency. SMT assembly requires specialized tooling and processes to mount components on both sides of the PCB in a single pass. Compared to traditional through-hole technology, this method offers superior flexibility in component placement and improves electrical performance. SMT also allows for faster turnaround times compared to other electronic components due to its automation features and advanced automation solutions such as pick-and-place machines. SMT assembly is particularly well-suited for high-volume production, which is why it is highly sought after in large-scale manufacturing .
Through-hole assembly
PTH (Plate Through-Hole) assembly is an electronics manufacturing service process that mounts electronic components onto a printed circuit board. PTH assemblies typically consist of pins inserted into holes in the circuit board and then soldered into place. PTH assemblies provide robust mechanical connections for electrical components, making them ideal for high-reliability applications such as automotive electronics or medical devices. PTH assemblies can also utilize multiple layers of copper wires and pads on both sides of the circuit board to create complex circuits. With proper design and quality assurance procedures, PTH assemblies can provide reliable performance over a long lifespan while saving costs due to their relatively lower material costs compared to other soldering techniques.
Manual assembly
Manual PCB assembly involves placing and soldering components onto a printed circuit board (PCB). This electronics manufacturing service process is typically used for situations requiring small-scale production or prototyping. Manual PCB assembly requires manual checks to ensure all parts are correctly placed and soldered, and testing the board’s functionality after assembly. For manual PCB assembly, experienced technicians using high-quality tools are essential to produce reliable results.
Phase 6: IC Programming
IC programming is a crucial component of the electronics manufacturing process, playing a vital role in the development and production of devices such as smartphones, computers, and other consumer electronics. IC programming involves writing code that tells an integrated circuit (IC) how to function when installed in a device. This code can include instructions on how the IC interacts with other components within the system and the tasks it should perform. IC programming is also used for testing during design verification and debugging, ensuring the IC functions correctly before delivery to the customer. Due to its importance in many industries, IC programming has become a valuable skill for those hoping to enter or develop a career in electronics manufacturing companies.
Phase 7: PCB Testing and Inspection ( AOI/Visual Inspection/Online Inspection )
At this stage, which is essentially a quality inspection phase, regardless of the product type, the process requires the following two inspection methods:
AOI inspection
AOI (Automated Optical Inspection) is an important part of the electronics manufacturing process. AOI inspection is a non-destructive testing method used to detect and identify defects in printed circuit boards (PCBs). It involves using optical technologies such as cameras, lasers, or X-rays to scan each component on the PCB to look for anomalies. Furthermore, AOI systems can be programmed to find specific types of defects, including missing components, incorrect polarity, short circuits between pins, interlayer misalignment, and other issues that could lead to product failure. Undoubtedly, AOI inspection provides manufacturers with an effective way to quickly and accurately identify potential problems before products are shipped for final assembly or packaging.
Appearance inspection
Visual inspection is a crucial electronics manufacturing service process in any manufacturing company because it helps ensure that produced electronic components meet high-quality standards. Visual inspection involves carefully examining electronic components and assemblies to look for any defects or inconsistencies that could affect their performance or reliability. This type of inspection requires careful observation, attention to detail, and an understanding of the technologies involved to quickly identify any anomalies. By using visual inspection methods, manufacturers can detect problems before they become more serious.
Online testing
In-Circuit Testing (ICT) is an electronics manufacturing service process used to check the correct function and physical integrity of electronic components and circuits. It is an important quality assurance tool in the development, production, and repair of electronic products. ICT involves connecting a specialized testing system to the circuit board under test and then running tests to detect errors or defects in the components or their connections on the board. This electronics manufacturing service process helps manufacturers ensure that their products meet design specifications before being placed on the market.
Phase 8: Electromechanical Assembly
Electromechanical assembly is a crucial part of the electronics manufacturing services process because it combines electronic and mechanical components to create more complex systems. By integrating circuits with physical components such as motors, actuators, sensors, and other devices, electromechanical assembly can produce highly efficient products for various industries. However, this electronics manufacturing services process requires a combination of engineering knowledge and skilled processes to ensure the accuracy of each electronic product. With advancements in technology and automation, electromechanical assembly is becoming increasingly popular due to its ability to reduce production time and improve quality control.
Phase 9: Functional Testing
Functional testing is crucial to the EMS process, ensuring that electronic products meet required specifications and function properly. Functional testing involves testing each device component to ensure they work seamlessly together. This includes compatibility, performance, reliability, and safety feature testing. By performing functional testing on electronic products within the EMS process, manufacturers can save time and money by avoiding costly defects or recalls later on.
Phase 10: Aging Test
Aging testing is an EMS process used to test the reliability of electronic components. It involves running equipment or systems under normal operating conditions for a period of time, typically simulating environmental conditions such as temperature and humidity. This allows for the identification and correction of any potential defects or problems that may arise during long-term use before the final product is released. By doing so, aging testing helps ensure that electronic products operate reliably throughout their expected lifespan.
Stage 11: Wire Bonding
Wire bonding is a critical EMS process that ensures secure connections between electronic components. This process involves connecting two parts using gold or aluminum wire. Wire bonding can connect multiple electronic components, ensuring they are securely connected and function properly. The most common type of wire bonding is ball bonding, where the ends of the lead are shaped into small spheres that contact the two electronic components being connected. Other types of bonding, such as wedge bonding or pin bonding, are also available and can be used depending on project requirements. Wire bonding provides a reliable connection between electronic components while ensuring they remain electrically isolated and operate undisturbed.
Stage Twelve: Conformal Coating
Conformal coating is an electronics manufacturing process that protects electronic circuits from extreme environmental conditions. This protective coating helps prevent corrosion and oxidation of electronic components and protects against dust, moisture, fungi, and other contaminants. Conformal coatings can also provide electrical insulation between components on circuit boards or other substrates.
Phase Thirteen: Final Quality Control (FQA)
Final Quality Assurance (FQA) is an essential step in EMS (Engineering, Manufacturing, and Supply) of electronic products. It involves inspecting and testing electronic components, assemblies, and products to ensure they meet predefined quality standards. FQA helps identify potential defects or problems that may affect product performance before the product reaches the end user. By implementing rigorous FQA procedures, electronics manufacturers can maintain a high level of quality assurance throughout the electronics manufacturing process and reduce costly recalls due to part or product failures.
Phase Fourteen: Customized Packaging
Custom packaging is the electronics manufacturing process that designs and manufactures unique packaging to meet the specific needs of electronic products. This packaging is crucial for protecting electronic components from environmental hazards such as dust, moisture, vibration, shock, and extreme temperatures. Custom packaging also helps reduce costs because it provides an efficient way to safely store and transport electronic products. Furthermore, custom packaging can help improve product performance and reliability by reducing the risk of damage during handling or transportation. Undoubtedly, manufacturers can leverage custom design techniques to ensure their electronic products are properly packaged while saving on production costs and time.
Engineering service process during EMS manufacturing
Electronic Manufacturing Services (EMS) covers the entire process from product development to mass production. To ensure that products meet design requirements and production needs, EMS engineering services are used to verify product designs through engineering testing at each stage, ultimately bringing the product to market.
EVT (Engineering Validation Test)
During the EVT phase, the initial goal is usually to create a Bigboard, which is a test board with full functionality. Then, through continuous verification and design, the board is scaled down and gradually made to meet functional and process requirements.
Design Validation Test (DVT)
During the DVT phase, the focus is on confirming whether the product’s appearance, structure, and function meet the design and process requirements, and on starting mold design to ensure that the quality of each part and structure is stable and meets the product’s required specifications and standards.
PVT (Production Validation Test)
During the PVT phase, trial production begins to verify the stability, capacity, and yield of the production process. Simultaneously, the engineering team designs test fixtures to improve testing efficiency and ensure manufacturing quality.
MP Mass Production
Once the PVT trial production is successfully completed, the product officially enters the mass production stage. The EMS manufacturer will continuously monitor the production yield to ensure the consistent quality of each batch of products, thereby ensuring the product’s reliability and competitiveness in the market.
Differences between EMS, ODM and OEM
EMS, ODM, and OEM are often confused, but they are different business models. Their business models are as follows.
EMS (Electronic Manufacturing Services)
EMS (Electronic Manufacturing Services) is a service where companies outsource the manufacturing and design of electronic devices to other companies. The EMS company handles the entire manufacturing process, including product design, prototyping, parts sourcing, circuit board assembly, product assembly, quality testing, and logistics management. This system allows client companies to streamline their manufacturing operations and focus on their core business. EMS is widely used in smartphones, home appliances, and communication equipment.
ODM (Original Design Manufacturer)
ODM (Original Design Manufacturer) is a contracting model that covers everything from product design to manufacturing. The ODM company handles all product design, prototyping, and manufacturing, while the client company sells the finished product under its own brand. ODM is particularly useful for companies looking to reduce product development resources and accelerate time-to-market for new products.
OEM (Original Equipment Manufacturer)
OEM is a business model in which a specialized manufacturing company produces products designed by a client company. The OEM company focuses on manufacturing, while the client company is responsible for design and brand management. The finished products are sold under the client company’s brand name. OEM is widely used when client companies use external manufacturers instead of owning their own production facilities to improve manufacturing efficiency and reduce costs.
Common industries requiring electronic manufacturing services
Electronic manufacturing services (EMS) are a comprehensive service that is needed by any industry that requires the procurement of PCBs, PCBAs, and related custom parts. The following are some of the industries that most frequently require EMS.
1. Medical Industry: PCBs are used in a variety of medical applications, including surveillance imaging, monitoring equipment and implantable medical devices.
2. Industry: Industrial applications range from industrial automation to robot motion control. Industrial engineers strive to maximize the efficiency of industrial processes by increasing throughput while reducing costs, making high-performance PCBs crucial. (Automotive industry, industrial design)
3. Aerospace and Defense: Quality systems take precedence over standard ECM service lists because electronics used in aerospace and military applications require high quality. (Drones, Two-Way Radios)
4. Telecommunications: There is currently a large demand for global telecommunications electronic manufacturing services (EMS). Based on smart technologies and telecommunications equipment, television and the internet connect all of us, machines, and global companies.
5. Consumer electronics: Electronic manufacturing services (EMS) have gained widespread acceptance in consumer electronics due to the increasing interconnectivity between a wide range of products, from audio products to wearable devices, games, and even virtual reality.
6. Lighting Technology: Our inductive ballasts feature current limiting to ensure the proper functioning of fluorescent lamps, LED high-pressure mercury lamps, sodium lamps, and metal halide lamps.
Why choose Geyuan Electronics? Your EMS solution partner
In the electronics manufacturing industry, finding a reliable and fully capable EMS partner is crucial for successful product launches. Geyuan Electronics boasts over 10 years of R&D and manufacturing experience, spanning consumer electronics, medical devices, automotive electronics, and industrial applications. We provide a one-stop service from design verification, pilot production, and small-batch production to mass production and international logistics. Our factory is certified to international standards such as ISO 13485 and IATF 16949, ensuring high-quality manufacturing and meeting the needs of various electronic products. Whether you are a startup or a large enterprise, Geyuan Electronics can be your strongest manufacturing support, enabling faster innovation and more efficient mass production. Want to learn more about our EMS services and success stories? Contact us today to start your smart manufacturing journey!