PCBA board production process

Abstract

The application discloses a PCBA board production process, comprising the following steps: step 1, material IQC and MES mistake-proof feeding: the IQC prints a unique UPN code on the incoming material to ensure the uniqueness of the material roll; the MES system performs first-in first-out and preferentially feeds tailing material, controls the usage according to the work order, realizes mistake-proof feeding, key material fool-proof and usage early warning; step 2, double-sided SMT high-precision processing: first, SMT on the BOT surface of the circuit board, and then SMT on the TOP surface of the circuit board, wherein the SMT on the BOT surface of the circuit board comprises laser engraving, board loading, printing, 3D SPI detection, patching, pre-furnace AOI, nitrogen reflow soldering, post-furnace AOI and X-Ray non-destructive detection of solder joints; the SMT on the TOP surface of the circuit board comprises board loading, printing, 3D SPI detection, patching, pre-furnace AOI, nitrogen reflow soldering, post-furnace AOI and X-Ray non-destructive detection of solder joints; step 3, test-assembly-packaging integrated delivery; the application solves the common problems in the industry, such as wrong material in the traditional process, insufficient precision, missing detection, difficult traceability and low efficiency.

Description

Technical Field

[0001] This invention relates to the field of printed circuit board (PCB) surface mount technology, and in particular to a PCBA board manufacturing process. Background Technology

[0002] As electronic devices evolve towards miniaturization, high density, and high reliability, PCBA manufacturing demands continuously increasing precision, yield, traceability, and delivery efficiency. Traditional PCBA production commonly suffers from the following technical deficiencies: 1. The lack of unique identification and error prevention mechanisms for materials leads to frequent occurrences of incorrect materials, mixed materials, and waste of surplus materials, making precise control impossible; 2. Insufficient printing and placement precision makes it difficult to stably process high-precision products such as 01005 devices, 0.3mm pitch devices, POP and sandwich structures; 3. Low detection coverage, relying solely on AOI, unable to detect hidden solder joints at the bottom, resulting in a high rate of missed detection for defects such as cold solder joints, empty solder joints, and air bubbles; 4. The production process lacks a complete traceability chain, making it impossible to quickly pinpoint the root cause of defective products; 5. Low level of automation, slow staff turnover, and long expansion cycle make it difficult to meet the demand for large-scale and rapid delivery.

[0003] Existing technologies are mostly improvements to single equipment or single processes, and have not formed a complete intelligent control and high-precision closed-loop process, which cannot meet the needs of high-end electronic products for high-quality, high-consistency, and high-efficiency PCBA manufacturing. Summary of the Invention

[0004] In view of this, the present invention addresses the shortcomings of the existing technology, and its main purpose is to provide a PCBA board manufacturing process that solves common industry problems such as incorrect materials, insufficient precision, lack of inspection, difficulty in traceability, and low efficiency in traditional processes.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A PCBA board manufacturing process includes the following steps: Step 1: Material IQC and MES error-proofing loading: IQC prints a unique UPN code on incoming materials to ensure the uniqueness of material rolls; the MES system implements first-in-first-out and prioritizes the issuance of leftover materials, controls usage according to work orders, and achieves error prevention in material loading, error prevention for critical materials, and usage warning. Step 2, Double-sided SMT high-precision processing: First, perform SMT on the BOT side of the circuit board, then perform SMT on the TOP side of the circuit board. The SMT steps for the BOT side of a circuit board include: laser engraving → board mounting → printing → 3D SPI inspection → surface mount → pre-reflow AOI → nitrogen reflow soldering → post-reflow AOI → X-Ray non-destructive testing of solder joints. The SMT steps for the top side of a circuit board include: board mounting → printing → 3D SPI inspection → component placement → pre-reflow AOI → nitrogen reflow soldering → post-reflow AOI → X-Ray non-destructive testing of solder joints. Furthermore, IPQC inspection is implemented throughout the entire process, forming a closed-loop process. Step 3, Integrated Delivery of Testing-Assembly-Packaging: Products completed with SMT will sequentially undergo testing, assembly, and packaging processes. Among them: the entire process adopts the MES system to achieve full-process traceability and error prevention, including the MES system to record and trace the entire process of warehousing, material issuance, production, testing, assembly and packaging; the MES system to realize test retest rate statistics, machine traceability, IMEI and software version anti-duplicate and error prevention; the MES system to automatically generate box number and pallet number and prevent duplication; and the MES system to realize real-time production data dashboard and report output. Furthermore, Six Sigma management is adopted to control the entire process in order to achieve control over quality and efficiency.

[0006] In one embodiment, the SMT process on the BOT side of the circuit board specifically includes the following steps: Laser engraving: A laser engraving machine is used to mark the preset positions on the BOT side of the circuit board to facilitate identification and positioning in subsequent processes; Board loading: Place multiple circuit boards to be processed into the placement area of ​​the board loading machine. The board loading machine feeds multiple circuit boards sequentially, with the BOT side of the circuit boards facing upwards. Printing: If there is no board at the exit of the printing machine, a board request signal is sent to the upper-level equipment, the board is fed in, and the printing machine prints solder paste on the designated position of the BOT side of the circuit board. 3D SPI Inspection: After the solder paste is printed on the BOT side of the circuit board, it enters the SPI inspection equipment to perform three-dimensional inspection on the solder paste; unqualified solder paste is alarmed and removed, while qualified solder paste enters the next process; Component Placement: Components that pass the solder paste inspection enter the placement machine, which places SMT components on the BOT side of the circuit board where solder paste has been applied. AOI before reflow: The board after surface mount technology (SMT) enters the first optical appearance inspection machine, which inspects the shape of the surface mount electronic components; SMT defective products are alarmed and removed, while qualified products proceed to the next process; Nitrogen reflow soldering: Qualified SMT components enter the reflow oven, where the solder paste on the circuit board is reflowed and heated to melt it. After cooling, the solder paste forms solder joints between the SMT components and the circuit board, achieving bonding. Post-reflow AOI: The circuit board after reflow soldering enters the second optical appearance inspection machine, which inspects the shape of the electronic components after reflow soldering; products that fail the reflow soldering inspection are alarmed and removed, while products that pass the reflow soldering inspection proceed to the next process; X-Ray Non-destructive Testing of Solder Joints: AOI qualified products after reflow enter the X-Ray inspection equipment, which performs three-dimensional tomographic scanning inspection on the bottom solder joints and hidden solder joints of BGA, QFN, and POP on the BOT side of the circuit board to identify defects such as cold solder joints, empty solder joints, bubbles, and bridging. Defective products are automatically isolated and uploaded to the MES system for tracking, while qualified products flow into the next process.

[0007] In one embodiment, the SMT step on the top side of the circuit board specifically includes the following steps: Board loading: Place multiple circuit boards with the BOT side SMT completed into the placement area of ​​the board loading machine. The board loading machine sequentially loads multiple circuit boards with the BOT side SMT completed, with the TOP side of the circuit boards facing upwards. Printing: If there is no board at the exit of the printing machine, a board request signal is sent to the upper-level equipment, the board is fed in, and the printing machine prints solder paste on the designated position of the TOP side of the circuit board. 3D SPI Inspection: After the solder paste is printed on the top side of the circuit board, it enters the SPI inspection equipment to perform three-dimensional inspection of the solder paste; unqualified solder paste is alarmed and removed, while qualified solder paste enters the next process; Component Placement: Components that pass the solder paste inspection enter the placement machine, which places SMT components on the solder paste application points on the top side of the circuit board. AOI before reflow: The board after surface mount technology (SMT) enters the first optical appearance inspection machine, which inspects the shape of the surface mount electronic components; SMT defective products are alarmed and removed, while qualified products proceed to the next process; Nitrogen reflow soldering: Qualified SMT components enter the reflow oven, where the solder paste on the circuit board is reflowed and heated to melt it. After cooling, the solder paste forms solder joints between the SMT components and the circuit board, achieving bonding. Post-reflow AOI: The circuit board after reflow soldering enters the second optical appearance inspection machine, which inspects the shape of the electronic components after reflow soldering; products that fail the reflow soldering inspection are alarmed and removed, while products that pass the reflow soldering inspection proceed to the next process; X-Ray Non-destructive Testing of Solder Joints: AOI qualified products after reflow enter the X-Ray inspection equipment, which performs three-dimensional tomographic scanning inspection on the bottom solder joints and hidden solder joints of BGA, QFN, and POP on the TOP side of the circuit board to identify defects such as cold solder joints, empty solder joints, bubbles, and bridging. Defective products are automatically isolated and uploaded to the MES system for tracking, while qualified products flow into the next process.

[0008] In one embodiment, step 2 employs full-node high-precision detection control, including: During the printing process, the printing accuracy is ±20μm, CMK>2.0, Cpk≥2.0, and it has automatic soldering and stencil accuracy detection functions; In the 3D SPI inspection process, the 3D SPI inspection measurement accuracy is as follows: thickness resolution is 1μm, Cpk≥2, repeatability GR&R≤10%, and 100% detection of insufficient tin, excessive tin, offset, and short circuit. In the surface mount process, surface mount technology supports 01005 devices, 0.3mm pitch, POP, and sandwich process production, with a mounting Cpk ≥ 1.67; In the nitrogen reflow soldering process, a 12-zone dual-rail nitrogen furnace is used for reflow soldering, with an oxygen content of ≤500ppm and a temperature control accuracy of ±1℃. In the pre-furnace AOI and post-furnace AOI steps, the pre-furnace / post-furnace 3D AOI resolution is 12μm, the minimum detection size is 01005 devices, and the detection rate is ≥98%. In the X-Ray solder joint non-destructive testing step, the X-Ray equipment resolution is ≤5μm, the number of tomographic scan layers is ≥8, the BGA / POP bubble rate detection accuracy is ≤1%, the empty solder / cold solder detection rate is ≥99.5%, and the test data is synchronized with the MES system in real time.

[0009] In one embodiment, in step 3, the capacity configuration includes: 30 SMT lines, 44 testing lines, 30 assembly lines, and 28 packaging lines, with a monthly capacity of 1500K and a delivery cycle of <5 days.

[0010] In one embodiment, the error prevention logic of the MES system is as follows: taking the work order as the core of management and control, binding the material UPN code, equipment parameters, and production process, and implementing the first-in-first-out + last-remaining material priority issuance rule. When loading materials, the UPN code is scanned to verify whether the material model, specifications, and batch match the work order. If they do not match, the equipment is locked to prevent production, thus achieving error prevention in material loading. A mandatory verification mechanism is set for key materials to prevent misuse and mixing. At the same time, the material usage is monitored in real time, and a usage warning is automatically issued when the usage is below the threshold to avoid material shortages, line stoppages, and excessive consumption. Furthermore, the MES system and X-Ray inspection equipment are interconnected, automatically associating the laser engraving code of the board with the solder joint inspection image to achieve full lifecycle traceability of hidden solder joints.

[0011] In one embodiment, the laser engraving step involves engraving the board serial number and batch code at a preset position on the BOT side of the circuit board for processing positioning, board identification, and full-process traceability, preventing board confusion.

[0012] In one embodiment, the entire process adopts joint management of TPM, 6Sigma, and OEE, with OEE > 45% and 6Sigma management achieving zero customer complaints, zero batch defects, and FFR ≤ 1%.

[0013] Compared with the prior art, the present invention has obvious advantages and beneficial effects. Specifically, as can be seen from the above technical solution: This invention uses IQC to print a unique UPN identifier, combined with the MES system to achieve first-in-first-out (FIFO) material handling, error prevention in material loading, error prevention for critical materials, full-process traceability of production, and automatic anti-duplicate measures for box / pallet numbers, thus eliminating the use of incorrect materials from the source and achieving 100% traceability of the entire production chain. This invention employs high-precision BOT / TOP double-sided SMT processing, achieving a closed-loop inspection system covering all nodes from printing to 3D SPI inspection, component placement, pre-reflow AOI, nitrogen reflow soldering, and post-reflow AOI. This enables high-precision, high-yield production of 01005 components, 0.3mm pitch, POP, and sandwich processes. The accuracy indicators of printing, component placement, reflow, and inspection equipment are linked and controlled, complemented by automatic soldering, stencil inspection, real-time reflow temperature monitoring, and a defect locking mechanism, ensuring stable and controlled operation throughout the entire process. Furthermore, it embeds double-sided X-ray solder joint non-destructive testing into the SMT process, specifically covering bottom and hidden solder joints of BGA, QFN, and POP components that cannot be inspected by AOI, forming a 3D... The four-layer full-dimensional inspection closed loop of SPI + pre-furnace AOI + post-furnace AOI + X-Ray covers both surface and hidden solder joints, with inspection coverage from surface to all solder joints, significantly improving yield and reliability, solving the problem of missed detection in high-density packaging. In addition, the MES system and X-Ray data are interconnected, automatically associating laser engraving codes with solder joint inspection images, realizing full lifecycle traceability of hidden solder joints, strengthening the uniqueness and integrity of full-process traceability, and realizing integrated linkage of equipment-data-traceability. This invention employs 6Sigma management to control the entire process, achieving FFR ≤ 1%, with zero batch defects and zero customer complaints. This invention enables efficient and rapid delivery, rapid capacity expansion, a monthly capacity of 1500K, intelligent production with fewer personnel, automation replacing 15% of manpower, reducing non-value-adding processes by 30%, and significantly improving production efficiency. This invention organically combines UPN unique coding, MES error prevention, 3D SPI, 3D AOI, nitrogen reflow, and 6Sigma quality control to form a collaborative solution design. It solves long-standing technical problems in the industry such as incorrect materials, missing materials, printing misalignment, poor soldering, poor welding, untraceable processes, and low efficiency, and achieves stable mass production of high-precision PCBA.

[0014] To more clearly illustrate the structural features, technical means, and specific objectives and functions achieved by the present invention, the present invention will be further described in detail below with reference to specific embodiments. Detailed Implementation

[0015] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit this application.

[0016] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0017] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0018] This application provides a PCBA board manufacturing process, including the following steps: Step 1: Material IQC and MES error-proofing loading: IQC prints a unique UPN code on incoming materials to ensure the uniqueness of each roll (i.e., IQC prints a unique material code on the incoming materials to ensure that each roll has a unique identification); the MES system implements first-in-first-out and prioritizes the issuance of leftover materials, controls the usage according to work orders, and realizes error prevention in material loading, error prevention for critical materials, and usage warning.

[0019] The MES system uses work orders as its core to implement first-in-first-out (FIFO) and prioritize the issuance of leftover materials. It verifies the matching between materials and work orders by scanning UPN codes, and locks the equipment if they do not match, thus achieving error prevention in material feeding, prevention of mistaken material handling, and usage warning.

[0020] In this application, the UPN code, or Unique Part Number, is a unique identification code printed by IQC for each incoming material roll, ensuring that the roll is uniquely identifiable throughout the entire process. Laser engraving is a marking used for board identification, processing positioning, and batch traceability. MES error prevention is an intelligent management logic based on work orders, combined with UPN codes, to achieve material verification, error-proofing during loading, and usage warnings.

[0021] In this application, the error prevention logic of the MES system is as follows: taking the work order as the core of control, binding the material UPN code, equipment parameters, and production process, and implementing the first-in-first-out + priority issuance rule for leftover materials; when loading materials, the UPN code is scanned to verify whether the material model, specifications, and batch match the work order. If they do not match, the equipment is locked to prevent production, thus achieving error prevention in material loading; a mandatory verification mechanism is set for key materials to prevent misuse and mixing, while the material usage is monitored in real time. If the usage is lower than the threshold, an automatic usage warning is issued to avoid material shortages, line stoppages, and excessive consumption; and the MES system and X-Ray inspection equipment are interconnected, automatically associating the laser engraving code of the board with the solder joint inspection image to achieve full lifecycle traceability of hidden solder joints.

[0022] Step 2, Double-sided SMT high-precision processing: First, perform SMT on the BOT side of the circuit board, then perform SMT on the TOP side of the circuit board. The SMT steps for the BOT side of a circuit board include: laser engraving → board mounting → printing → 3D SPI inspection → surface mount → pre-reflow AOI → nitrogen reflow soldering → post-reflow AOI → X-Ray non-destructive testing of solder joints. The SMT steps for the top side of a circuit board include: board mounting → printing → 3D SPI inspection → component placement → pre-reflow AOI → nitrogen reflow soldering → post-reflow AOI → X-Ray non-destructive testing of solder joints. Furthermore, IPQC inspection is implemented throughout the entire process, forming a closed-loop process; and, in this step, high-precision detection and control are adopted at all nodes, including: During the printing process, the printing accuracy is ±20μm, CMK>2.0, Cpk≥2.0, and it has automatic soldering and stencil accuracy detection functions; In the 3D SPI inspection process, the 3D SPI inspection measurement accuracy is as follows: thickness resolution is 1μm, Cpk≥2, repeatability GR&R≤10%, and 100% detection of insufficient tin, excessive tin, offset, and short circuit. In the surface mount process, surface mount technology supports 01005 devices, 0.3mm pitch, POP, and sandwich process production, with a mounting Cpk ≥ 1.67; In the nitrogen reflow soldering process, a 12-zone dual-rail nitrogen furnace is used for reflow soldering, with an oxygen content of ≤500ppm and a temperature control accuracy of ±1℃. In the pre-furnace AOI and post-furnace AOI steps, the pre-furnace / post-furnace 3D AOI resolution is 12μm, the minimum detection size is 01005 devices, and the detection rate is ≥98%. In the X-Ray solder joint non-destructive testing step, the X-Ray equipment resolution is ≤5μm, the number of tomographic scan layers is ≥8, the BGA / POP bubble rate detection accuracy is ≤1%, the empty solder / cold solder detection rate is ≥99.5%, and the test data is synchronized with the MES system in real time to form quantifiable technical parameters.

[0023] Step 3, Integrated Delivery of Testing-Assembly-Packaging: After SMT is completed, the products will sequentially enter the testing, assembly and packaging processes; and the capacity configuration includes: 30 SMT lines, 44 testing lines, 30 assembly lines and 28 packaging lines, with a monthly capacity of 1500K and a delivery cycle of <5 days.

[0024] Specifically, the entire production process utilizes the MES system for full-process traceability and error prevention. This includes the MES system recording and tracing the entire process from warehousing, material issuance, production, testing, assembly, and packaging; the MES system performing test retest rate statistics, machine traceability, and IMEI and software version error prevention; the MES system automatically generating box numbers and pallet numbers and preventing duplicates; and the MES system enabling real-time production data visualization and report output. In short, the entire production process uses the MES system for production management, error prevention, and traceability.

[0025] Furthermore, 6Sigma management is adopted to control the entire process, thereby achieving control over quality and efficiency. Specifically, lean 6Sigma quality and efficiency control is implemented, with TPM, 6Sigma, and OEE jointly managed throughout the entire process. OEE > 45%, 6Sigma management achieves zero customer complaints, zero batch defects, and FFR ≤ 1%. By integrating lean production, 6Sigma management, and intelligent automation, 30% of value-free processes are reduced, 15% of manpower is replaced, UPPH is increased by 30%, OEE > 45%, and efficient delivery with fewer people is achieved.

[0026] The SMT process on the BOT side of the circuit board specifically includes the following steps: Laser engraving: A laser engraving machine is used to mark preset positions on the BOT side of the circuit board to facilitate identification and positioning in subsequent processes. The engraving content includes the board serial number, batch code, etc. This laser engraving step engraves the board serial number and batch code at preset positions on the BOT side of the circuit board for processing positioning, board identification, and full-process traceability, preventing board confusion. Specifically, laser engraving is used to engrave permanent marks such as material batch, production serial number, and board identification code at preset positions on the BOT side of the circuit board. This is used for subsequent processes to quickly identify the board's identity, locate the processing area, and distinguish production batches. At the same time, it facilitates full-process traceability and rapid location of defective products, avoids board confusion, and improves processing positioning accuracy and traceability efficiency. Board loading: Place multiple circuit boards to be processed into the placement area of ​​the board loading machine. The board loading machine feeds multiple circuit boards sequentially, with the BOT side of the circuit boards facing upwards. Printing: If there is no board at the exit of the printing machine, a board request signal is sent to the upper-level equipment, the board is fed in, and the printing machine prints solder paste on the designated position of the BOT side of the circuit board. 3D SPI Inspection: After the solder paste is printed on the BOT side of the circuit board, it enters the SPI inspection equipment to perform three-dimensional inspection on the solder paste; unqualified solder paste is alarmed and removed, while qualified solder paste enters the next process; Component Placement: Components that pass the solder paste inspection enter the placement machine, which places SMT components on the BOT side of the circuit board where solder paste has been applied. AOI before reflow: The board after surface mount technology (SMT) enters the first optical appearance inspection machine, which inspects the shape of the surface mount electronic components; SMT defective products are alarmed and removed, while qualified products proceed to the next process; Nitrogen reflow soldering: Qualified SMT components enter the reflow oven, where the solder paste on the circuit board is reflowed and heated to melt it. After cooling, the solder paste forms solder joints between the SMT components and the circuit board, achieving bonding. Post-reflow AOI: The circuit board after reflow soldering enters the second optical appearance inspection machine, which inspects the shape of the electronic components after reflow soldering; products that fail the reflow soldering inspection are alarmed and removed, while products that pass the reflow soldering inspection proceed to the next process; X-Ray Non-destructive Testing of Solder Joints: AOI qualified products after reflow enter the X-Ray inspection equipment, which performs three-dimensional tomographic scanning inspection on the bottom solder joints and hidden solder joints of BGA, QFN, and POP on the BOT side of the circuit board to identify defects such as cold solder joints, empty solder joints, bubbles, and bridging. Defective products are automatically isolated and uploaded to the MES system for tracking, while qualified products flow into the next process.

[0027] The SMT process on the top side of the circuit board specifically includes the following steps: Board loading: Place multiple circuit boards with the BOT side SMT completed into the placement area of ​​the board loading machine. The board loading machine sequentially loads multiple circuit boards with the BOT side SMT completed, with the TOP side of the circuit boards facing upwards. Printing: If there is no board at the exit of the printing machine, a board request signal is sent to the upper-level equipment, the board is fed in, and the printing machine prints solder paste on the designated position of the TOP side of the circuit board. 3D SPI Inspection: After the solder paste is printed on the top side of the circuit board, it enters the SPI inspection equipment to perform three-dimensional inspection of the solder paste; unqualified solder paste is alarmed and removed, while qualified solder paste enters the next process; Component Placement: Components that pass the solder paste inspection enter the placement machine, which places SMT components on the solder paste application points on the top side of the circuit board. AOI before reflow: The board after surface mount technology (SMT) enters the first optical appearance inspection machine, which inspects the shape of the surface mount electronic components; SMT defective products are alarmed and removed, while qualified products proceed to the next process; Nitrogen reflow soldering: Qualified SMT components enter the reflow oven, where the solder paste on the circuit board is reflowed and heated to melt it. After cooling, the solder paste forms solder joints between the SMT components and the circuit board, achieving bonding. Post-reflow AOI: The circuit board after reflow soldering enters the second optical appearance inspection machine, which inspects the shape of the electronic components after reflow soldering; products that fail the reflow soldering inspection are alarmed and removed, while products that pass the reflow soldering inspection proceed to the next process; X-Ray Non-destructive Testing of Solder Joints: AOI qualified products after reflow enter the X-Ray inspection equipment, which performs three-dimensional tomographic scanning inspection on the bottom solder joints and hidden solder joints of BGA, QFN, and POP on the TOP side of the circuit board to identify defects such as cold solder joints, empty solder joints, bubbles, and bridging. Defective products are automatically isolated and uploaded to the MES system for tracking, while qualified products flow into the next process.

[0028] In summary, this invention uses IQC to print a unique UPN identifier, combined with the MES system, to achieve first-in-first-out (FIFO) material handling, error prevention in material loading, error prevention for critical materials, full-process traceability of production, and automatic anti-duplicate measures for box / pallet numbers. This eliminates the use of incorrect materials from the source and achieves 100% traceability of the entire production chain.

[0029] This invention employs high-precision BOT / TOP double-sided SMT processing, achieving a closed-loop inspection system covering all nodes from printing to 3D SPI inspection, component placement, pre-reflow AOI, nitrogen reflow soldering, and post-reflow AOI. This enables high-precision, high-yield production of 01005 components, 0.3mm pitch, POP, and sandwich processes. The accuracy indicators of printing, component placement, reflow, and inspection equipment are linked and controlled, complemented by automatic soldering, stencil inspection, real-time reflow temperature monitoring, and a defect locking mechanism, ensuring stable and controlled operation throughout the entire process. Furthermore, it embeds double-sided X-ray solder joint non-destructive testing into the SMT process, specifically covering bottom and hidden solder joints of BGA, QFN, and POP components that cannot be inspected by AOI, forming a 3D... The four-layer, all-dimensional inspection closed loop of SPI + pre-furnace AOI + post-furnace AOI + X-Ray covers both surface and hidden solder joints, significantly improving yield and reliability by extending inspection coverage from the surface to all solder joints. This solves the problem of missed detection in high-density packaging. Furthermore, the MES system and X-Ray data are interconnected, automatically linking laser-engraved codes with solder joint inspection images to achieve full lifecycle traceability of hidden solder joints. This strengthens the uniqueness and integrity of the entire process traceability and realizes integrated linkage between equipment, data, and traceability.

[0030] This invention employs 6Sigma management to control the entire process, achieving an FFR of ≤1% and zero batch defects and customer complaints. This invention enables efficient and rapid delivery, rapid capacity expansion, a monthly capacity of 1500K, intelligent production with reduced manpower, automation replacing 15% of manpower, reducing non-value-adding processes by 30%, and significantly improving production efficiency.

[0031] This invention organically combines UPN unique coding, MES error prevention, 3D SPI, 3D AOI, nitrogen reflow, and 6Sigma quality control to form a collaborative solution design. It solves long-standing technical problems in the industry such as incorrect materials, missing materials, printing misalignment, poor soldering, poor welding, untraceable processes, and low efficiency, and achieves stable mass production of high-precision PCBA.

[0032] The above description is merely a preferred embodiment of the present invention and does not constitute any limitation on the technical scope of the present invention. Therefore, any minor modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A PCBA board manufacturing process, characterized in that: Includes the following steps: Step 1: Material IQC and MES error-proofing loading: IQC prints a unique UPN code on incoming materials to ensure the uniqueness of each roll. The MES system implements first-in-first-out and prioritizes the issuance of leftover materials, controls usage according to work orders, and achieves error prevention in material loading, foolproofing of critical materials, and usage warning. Step 2, Double-sided SMT high-precision processing: First, perform SMT on the BOT side of the circuit board, then perform SMT on the TOP side of the circuit board. The SMT steps for the BOT side of a circuit board include: laser engraving → board mounting → printing → 3D SPI inspection → surface mount → pre-reflow AOI → nitrogen reflow soldering → post-reflow AOI → X-Ray non-destructive testing of solder joints. The SMT steps for the top side of a circuit board include: board mounting → printing → 3D SPI inspection → component placement → pre-reflow AOI → nitrogen reflow soldering → post-reflow AOI → X-Ray non-destructive testing of solder joints. Furthermore, IPQC inspection is implemented throughout the entire process, forming a closed-loop process. Step 3, Integrated Delivery of Testing-Assembly-Packaging: Products completed with SMT will sequentially undergo testing, assembly, and packaging processes. Among them: the entire process adopts the MES system to achieve full-process traceability and error prevention, including the MES system to record and trace the entire process of warehousing, material issuance, production, testing, assembly and packaging; the MES system to realize test retest rate statistics, machine traceability, IMEI and software version anti-duplicate and error prevention; the MES system to automatically generate box number and pallet number and prevent duplication; and the MES system to realize real-time production data dashboard and report output. Furthermore, Six Sigma management is adopted to control the entire process in order to achieve control over quality and efficiency.

2. The PCBA board manufacturing process according to claim 1, characterized in that: The SMT process on the BOT side of the circuit board specifically includes the following steps: Laser engraving: A laser engraving machine is used to mark the preset positions on the BOT side of the circuit board to facilitate identification and positioning in subsequent processes; Board loading: Place multiple circuit boards to be processed into the placement area of ​​the board loading machine. The board loading machine feeds multiple circuit boards sequentially, with the BOT side of the circuit boards facing upwards. Printing: If there is no board at the exit of the printing machine, a board request signal is sent to the upper-level equipment, the board is fed in, and the printing machine prints solder paste on the designated position of the BOT side of the circuit board. 3D SPI Inspection: After the solder paste is printed on the BOT side of the circuit board, it enters the SPI inspection equipment to perform three-dimensional inspection on the solder paste; unqualified solder paste is alarmed and removed, while qualified solder paste enters the next process; Component Placement: Components that pass the solder paste inspection enter the placement machine, which places SMT components on the BOT side of the circuit board where solder paste has been applied. AOI before reflow: The board after surface mount technology (SMT) enters the first optical appearance inspection machine, which inspects the shape of the surface mount electronic components; SMT defective products are alarmed and removed, while qualified products proceed to the next process; Nitrogen reflow soldering: Qualified SMT components enter the reflow oven, where the solder paste on the circuit board is reflowed and heated to melt it. After cooling, the solder paste forms solder joints between the SMT components and the circuit board, achieving bonding. Post-reflow AOI: The circuit board after reflow soldering enters the second optical appearance inspection machine, which inspects the shape of the electronic components after reflow soldering; products that fail the reflow soldering inspection are alarmed and removed, while products that pass the reflow soldering inspection proceed to the next process; X-Ray Non-destructive Testing of Solder Joints: AOI qualified products after reflow enter the X-Ray inspection equipment, which performs three-dimensional tomographic scanning inspection on the bottom solder joints and hidden solder joints of BGA, QFN, and POP on the BOT side of the circuit board to identify defects such as cold solder joints, empty solder joints, bubbles, and bridging. Defective products are automatically isolated and uploaded to the MES system for tracking, while qualified products flow into the next process.

3. The PCBA board manufacturing process according to claim 1, characterized in that: The SMT process on the top side of the circuit board specifically includes the following steps: Board loading: Place multiple circuit boards with the BOT side SMT completed into the placement area of ​​the board loading machine. The board loading machine sequentially loads multiple circuit boards with the BOT side SMT completed, with the TOP side of the circuit boards facing upwards. Printing: If there is no board at the exit of the printing machine, a board request signal is sent to the upper-level equipment, the board is fed in, and the printing machine prints solder paste on the designated position of the TOP side of the circuit board. 3D SPI Inspection: After the solder paste is printed on the top side of the circuit board, it enters the SPI inspection equipment to perform three-dimensional inspection of the solder paste; unqualified solder paste is alarmed and removed, while qualified solder paste enters the next process; Component Placement: Components that pass the solder paste inspection enter the placement machine, which places SMT components on the solder paste application points on the top side of the circuit board. AOI before reflow: The board after surface mount technology (SMT) enters the first optical appearance inspection machine, which inspects the shape of the surface mount electronic components; SMT defective products are alarmed and removed, while qualified products proceed to the next process; Nitrogen reflow soldering: Qualified SMT components enter the reflow oven, where the solder paste on the circuit board is reflowed and heated to melt it. After cooling, the solder paste forms solder joints between the SMT components and the circuit board, achieving bonding. Post-reflow AOI: The circuit board after reflow soldering enters the second optical appearance inspection machine, which inspects the shape of the electronic components after reflow soldering; products that fail the reflow soldering inspection are alarmed and removed, while products that pass the reflow soldering inspection proceed to the next process; X-Ray Non-destructive Testing of Solder Joints: AOI qualified products after reflow enter the X-Ray inspection equipment, which performs three-dimensional tomographic scanning inspection on the bottom solder joints and hidden solder joints of BGA, QFN, and POP on the TOP side of the circuit board to identify defects such as cold solder joints, empty solder joints, bubbles, and bridging. Defective products are automatically isolated and uploaded to the MES system for tracking, while qualified products flow into the next process.

4. The PCBA board manufacturing process according to claim 1, characterized in that: In step 2, high-precision detection and control across all nodes is employed, including: During the printing process, the printing accuracy is ±20μm, CMK>2.0, Cpk≥2.0, and it has automatic soldering and stencil accuracy detection functions; In the 3D SPI inspection process, the 3D SPI inspection measurement accuracy is as follows: thickness resolution is 1μm, Cpk≥2, repeatability GR&R≤10%, and 100% detection of insufficient tin, excessive tin, offset, and short circuit. In the surface mount process, surface mount technology supports 01005 devices, 0.3mm pitch, POP, and sandwich process production, with a mounting Cpk ≥ 1.67; In the nitrogen reflow soldering process, a 12-zone dual-rail nitrogen furnace is used for reflow soldering, with an oxygen content of ≤500ppm and a temperature control accuracy of ±1℃. In the pre-furnace AOI and post-furnace AOI steps, the pre-furnace / post-furnace 3D AOI resolution is 12μm, the minimum detection size is 01005 devices, and the detection rate is ≥98%. In the X-Ray solder joint non-destructive testing step, the X-Ray equipment resolution is ≤5μm, the number of tomographic scan layers is ≥8, the BGA / POP bubble rate detection accuracy is ≤1%, the empty solder / cold solder detection rate is ≥99.5%, and the test data is synchronized with the MES system in real time.

5. The PCBA board manufacturing process according to claim 1, characterized in that: In step 3, the capacity configuration includes: 30 SMT lines, 44 testing lines, 30 assembly lines, and 28 packaging lines, with a monthly capacity of 1500K and a delivery cycle of less than 5 days.

6. The PCBA board manufacturing process according to claim 1, characterized in that: The error prevention logic of the MES system is as follows: taking the work order as the core of management and control, binding the material UPN code, equipment parameters, and production process, and implementing the first-in-first-out (FIFO) + priority issuance of leftover materials rule. When loading materials, the UPN code is scanned to verify whether the material model, specifications, and batch match the work order. If they do not match, the equipment is locked to prevent production, thus achieving error prevention in material loading. A mandatory verification mechanism is set for key materials to prevent misuse and mixing. At the same time, the material usage is monitored in real time, and a usage warning is automatically issued when the usage is below the threshold to avoid material shortages, line stoppages, and excessive consumption. In addition, the MES system and X-Ray inspection equipment are interconnected, automatically associating the laser engraving code of the board with the solder joint inspection image to achieve full life cycle traceability of hidden solder joints.

7. The PCBA board manufacturing process according to claim 1, characterized in that: The laser engraving step involves engraving the board serial number and batch code at a preset position on the BOT side of the circuit board. This is used for processing positioning, board identification, and full-process traceability to prevent board confusion.

8. The PCBA board manufacturing process according to claim 1, characterized in that: The entire process adopts TPM, 6Sigma, and OEE joint management, with OEE > 45% and 6Sigma management achieving zero customer complaints, zero batch defects, and FFR ≤ 1%.