QT-00688Ver1.0 SMT回流和固化制程的控制要求.doc

SUZHOUSMT Reflow/Cure Process ControlSMT回流和固化制程的控制要求信息分类： 三阶文件文件编号: QT-00688版本:1.0页码:13 of 23三阶文件1.Product Revision 产品版本Product Name产品名称Applicable Product BOM Revision适用的产品BOM版本2.Change history更改记录Updated Ver.最新版本Effective date 生效日期Prepared by起草人Brief of Amendments更改内容摘要3.Purpose目的The purpose of this document is to establish the process controls required for the SMT reflow and cure processes. 这份文件的目的是建立SMT回流和固化制程的控制要求.4.Scope范围This document identifies best practices for ENICS on the reflow soldering process. 这份文件确定ENICS在印刷制程上的良好实践.5.Definitions定义IPC-T-50 - Terms and Definitions for Interconnecting and Packaging Electronic Circuits.IPC-T-50 电子装联产品的术语和定义6.Responsibilities职责 SMT operators It is the responsibility of the SMT Operator to ensure the correct profile program is loaded.SMT作业员负责正确加载回流炉程序.SMT TechniciansIt is the responsibility of the technician to ensure that the profiles are available, and any new profiles are not saved as a Datapaq profile until they are within specification, and also be responsible for fabricating testing profile board, testing profile and printing the profile.SMT技术人员负责确保炉温曲线的有效性，保存符合规格要求的炉温曲线，并且负责制作炉温测试板，测试炉温并打印炉温曲线.SMT Line Supervisors It is the responsibility of the SMT Line Supervisors to ensure only trained operators are loading profiles into the machine.SMT线主管负责确保只有培训合格的作业员才能加载回流炉程序.SMT Engineer It is the responsibility of the SMT Engineer to indicate on any ECN, the requirement to re-profile an assembly, where the changes made could affect the thermal properties of that assembly and therefore the solderability of components, also be responsible for setting DataPaq software configuration, temperature parameter and verify the profile testing result. SMT工程师负责指出任何的ECN，重测炉温的要求，哪些更改可能会影响产品的热性能和元件的可焊性，而且负责设置DataPaq软件配置，炉温参数和确认炉温曲线结果.QA technicainsIt is the responsibility of the QA technicians to verify whether on duty SMT technicians test profile, print profile, paste it on the reflows designated area or not. QA检查并确认当班SMT技术人员是否测试、打印、张贴炉温曲线于炉子的指定区域.7.Description描述7.1 Thermocouple Attachment固定热电耦 The thermocouple junction must make direct, reliable thermal contact with the surface being monitored. The accuracy and reaction time of the measurement is very dependent on the quality of the attachment method. Additionally, since a Thermocouples response is dependent on the thermal mass of the thermocouple and attachment material, it is critical to minimize variation and amount of material used to accurately attach the thermocouple to the PCA. 热电耦要直接与被测物连接, 以确保热电耦与被测物体的表面有可靠的热接触，测量的精度和反应时间依赖于固定热电耦的质量.另外热电耦的反应是依赖于聚集在热电耦和被测物上的热量,把热电耦精确地贴在PCA上让其变化降到最小是很关键的. The preferred method of thermocouple attachment is to encapsulate the thermocouple in with a highly conductive aluminum tape with conductivity greater than 0.45 W/m-K or equitant high temperature tape on a reflow soldered Printed Circuit Board (PCB). The method of attachment is: 固定热电藕首选的方法是使用有良好导热功能的铝片和大于0.45 W/m-K或者套折的高温胶带贴在回流焊的PCB上.7.1.1 Select a Type K 0.005” wire diameter thermocouple.Note: The Type K thermocouple has a yellow connector (See Figure 1).选择K型直径是0.005” 的热电耦注: K型直径热电耦有黄色接头(看图 1).Figure 1: K-Type Thermocouple图 1: TK型的热电耦7.1.2 Verify the weld bead of the thermocouple is not cracked or open (See Figure 2).检查热电耦的端头没有裂缝.（看图2）Figure 2: Thermocouple weld bead with insulation properly stripped from the tip图 2: 热电耦端头上的绝缘层被正确剥去7.1.3 Locate the thermocouple weld bead at the joint of the SMT solder joint and cover the joint with an approximate 3mm x 3mm aluminum tape. Finally cover the wire, thermocouple bead and solder joint area with Kapton tape. (See Figure 3-5).将热电耦的焊珠定位于SMT的焊点上,使用一个大约3mm X 3mm 的铝片将焊点覆盖住,最后使用高温胶带纸将线 ,热电耦上的焊珠 , 焊点一起盖住.Figure 3: Method attachment of thermocouples for SMT reflow profiling图3： SMT回流温度曲线热电耦固定方法相关部门审核 Figure 5: Improper size thermal pad and attachment which will absorb additional heat and come free because of the lack of Kapton tape.图5:不适当尺寸热片及配置将由于缺乏高温胶带而吸收额外的热量.Figure 4: Proper size Aluminum pad and attachment technique图4:适当尺寸的铝片及固定技术7.1.4 Route the thermocouple wire out to the center rear edge of the PCB. Do not route over components, securing the wire with Kapton Tape. (See Figure 6)热电耦的金属线从PCB中间走到PCB边沿，不要跨在元件上，使用高温胶带来固定热电耦金属线.（看图6）Figure 6: Thermocouple routing configuration图6：热电耦的走线7.2 Profiling Software温度曲线测量软件7.2.1 Profile Approval温度曲线建立的批准The development of a profile must be done in accordance with Reflow profile testing WI. The completion of Profile Testing Training is the criteria for profile creation and approval. Training records will be maintained on the appropriate site system.建立一条温度曲线必须和回流炉炉温测试指引一致.完成炉温测试培训是温度曲线建立和批准的评判标准. 培训记录将要维护在一个适当的工厂系统.Once approval is received, the resource is able to create profiles based on the solder specification, assembly specification and customer requirements without receiving additional approval. For resources in training of profiling, all profiles are required to be approved by an approved resource.一旦获得批准，就可以根据焊膏规格,装配规格,客户要求建立曲线而不需另外的审核，对于还在接受建立曲线知识培训的人员，所建立的曲线都要经过有资格建立曲线人员的签名确认.7.2.2 Profile testing flow chart:炉温测试流程图SMT engineer is responsible for setting reflow each zones temperature and conveyor speed according to current WI.SMT工程师依据本指引要求进行设定各温区温度及链速.QA is responsible for verifying whether SMT technician test profile, print profile and paste it on the reflows designated area or not. QA检查并确认当班SMT技术人员是否测试、打印、张贴炉温曲线.SMT technician is responsible for printing the profile and paste it on the reflows designated area, its valid with engineers signature, and inform production personnel to produce.SMT技术人员将测试OK的炉温曲线打印并张贴在炉子的指定区域，工程师须签字才有效，通知生产人员可以过炉生产.SMT engineer is responsible for verifying the profile test result, if NG, engineerll adjust reflow parameter till its OK. SMT工程师对测试结果进行判定，如果测试结果不合格，工程师修改炉温参数，技术员再测试，直到结果OK为止.SMT technician is responsible for fabricating profile testing board and testing reflow profile according to WI.SMT技术人员依据QT-00280 DATAPAQ 炉温测试指引进行炉温测试.7.2.3 Load reflow program If the oven profile is available the Operator should load the profile and check that the name of the profile matches the assembly number. Once loaded the operator should check the oven rail width, against the profile set up board. Once this has been validated it is OK to resume running.If the profile does not match board assembly number, the assembly will need to be profiled and verified by a technician before proceeding.If there is a down-level profile available, this should not be used until the technician confirms its suitability and or re-profiles the assembly saving the new profile against the updated assembly number or revision.Decision process to run with valid oven profile recipesOven Profile Exists and Name matches with product change over check listYES NOBoard has had Physical changes.Profile Exists YESNOYESNORunStore Valid ProfileRe-Profile boardRename Profile to current Assembly part and Rev.7.3 Required Fields / Info and Definitions需要区域/信息和定义For a profile to be accurately recorded the following information is required to be part of the profile file.温度曲线要求精确记录以下信息1. Heating Zone top and bottom temperatures by each zone of the oven.炉子每个温区的上下加热器的设定温度.2. Cooling zone settings降温区的设定.3. Conveyor Speed传送带的速度.4. Probe locations on the assembly by reference locations探头的位置在装配板上的位号.5. If a reflow support pallet is required回流托盘治具, 如果有使用.7.4 Naming and file location standard 命名与文件存放标准Enics will adopt a standard profile naming convention by Line to ensure constancy and portability of the profiles from one line to another line. The structure shall include the following information:Enics将要给各个产线采用一条标准的命名规则,以确保温度曲线从一条产线转移到另一条产线时的稳定不变和方便转移.由以下几点信息构成:1. Customer Name 客户名2. Assembly Number装配名3. SMT Side装配面4. Profile Revision温度曲线版本Reflow program naming rules: 回流炉程序名命名规则：Assembly Number-SMT Side Profile Revision如： 70CVB01129-T Ver1.0DataPaq Profile naming rules: DataPaq温度曲线命名规则：Customer NameAssembly NumberSMT SideProfile Revision_Line#如：Vacon70CVB01129TVer1.0_Line1When a revision to a profile or a revision to an assembly occurs, the older profile needs to be saved.当一种曲线的版本或装配的版本发生变化时,旧的曲线需要存储.Enics Suzhou must specify and implement on all new profiles the file storage location and file naming structure. The file storage location must be a network drive with nightly backups. Where no facility exists for networked backups, these backups must be done monthly.The Path for reflow storage is: Cnbe115beijing$22000.EngineeringProcessEnics苏州必须规定和执行所有新的温度曲线文件的储存放置及命名.文件存储位置必须是一个带有夜间备份的局域网络驱动器. 如果没有网络备份，这些备份必须每月备份.温度曲线存放路径：Cnbe115beijing$22000.EngineeringProcess7.5 Profile Measurements测量数据7.5.1 Datum Structure数据构成The datum structure of a reflow profile are points on a temperature profile defining critical measurement parameters. It is critical that a consistent datum structure is applied to insure compliance to component and material specifications. There are 10 critical datum in reflow profiling (See Figure 7).一条回流曲线的数据结构是指温度曲线的关键测量参数，保持稳定的关键参数构成对评估曲线符合元件和材料的规格的一致是很关键的.在回流曲线中有10个关键数据.（看图7）Figure 7: Datum Structure of a reflow profile1. Data Start. 开始值The data start a maximum temperature in which the maximum slope is found. This value for Enics is 25 C.数据开始收集时的温度,最大升温斜率会出现在这段区域里.Enics的开始温度是25C.2. Maximum Positive Ramp Rate最大的正斜率.The maximum positive slope is defined as the thermocouple measurement where the slope of the reading calculated on a 10 second interval is a maximum between the Data Start and the Peak Temperature for ramp to spike profiles and the soak Temperature for ramp / soak profiles for all the thermocouples measurements.最大的正温升斜率定义为: 给成斜坡直接升到峰值的曲线和斜坡/浸润曲线浸润温度的所有热电耦以10秒时间为间隔, 在数据开始和峰值温度之间温度蔓延到曲线最尖的部分时所计算出的最大斜率读数.3. Rise Slope升温斜率The rise slope is calculated from thermocouple measurements at the data start to the liquidus temperature for the ramp to spike profile and to the minimum soak temperature for the ramp soak profile. 升温斜率是从热电耦数据开始测量到液化温度的计算.4. Minimum Soak Temperature最小的浸润温度The minimum soak temperature is where the flux of the solder paste becomes active. This temperature is unique to the materials being used.最小浸润温度是锡膏中助焊剂开始活跃的温度，这个温度因所使用的焊膏的不同而不同.SUZHOUSMT Reflow/Cure Process ControlSMT回流和固化制程的控制要求信息分类： 三阶文件文件编号: 版本:1.0页码:23 of 235. Maximum Soak Temperature最大浸润温度The maximum soak temperature is where the flux of the solder paste begins to reduce its activity. This temperature is unique to the materials being used.最大浸润温度是锡膏中助焊剂活跃性开始降低的温度，这个温度因所使用的焊膏的不同而不同.6. Time to Peak峰值时间The time to peak is a measure of the time from the data start to the peak temperature.峰值时间是一种从数据开始到峰值温度的测量时间.7. Soak Time浸润时间The soak time is measured by each thermocouple and is defined as the difference in time when the measurement matches the maximum soak temperature and the minimum soak temperature.浸润时间由每根热电耦测量，是指每条曲线到达最大浸润温度和最小浸润温度的时间差.8. Delta Temperature (DT) Delta温度The delta Temperature is measured when the first thermocouple reaches liquidus. This measurement then references the temperature of all thermocouples at this time to determine the maximum delta from the liquidus temperature.Delta温度是当第一根热电耦到达液化温度时各条曲线的最大温度差.9. Minimum Peak Temperature最小的峰值温度The minimum peak temperature is the lowest peak temperature reading of the thermocouples used for measurement.最小的峰值温度是热电耦测量时读取的最低峰值温度.10. Maximum Peak Temperature最大的峰值温度The maximum peak temperature is the highest temperature recorded by any thermocouple. 最大的峰值温度是热电耦记录的最大的峰值温度.11. Time Above Liquidus (TAL) 液化线以上时间The time above liquidus is measured in seconds for each thermocouple from when the solder metallurgy first begins to become liquidus according to a phase diagram. The time is terminated when the measured temperature drops below this temperature. Table 1: outlines the liquidus temperatures for various metallurgies.Liquidus TemperaturesSn63Pb37183 CSn60Pb40183 CSn62Pb36 Ag179 CSnAg3.0 Cu0.5217 CTable 1: Liquidus Temperature for various metallurgies液化线以上时间是每条热电耦测量到焊锡合金处于液化温度以上的时间，当测量温度下降到低于液化温度时液化时间结束.表1：不同合金的液化温度.12. Maximum Negative Slope最大的降温斜率The maximum negative slope is defined as the thermocouple measurement from the peak temperature to the where the thermocouple reaches 150C .最大的降温斜率是指电热耦测量从峰值温度下降到150C的最大斜率.7.6 Profile Shapes 曲线的形状Three shapes of thermal profiles are common in the manufacture of PCAs.生产PCAs通常温度曲线有三种形状.1) Top Hat (Cure Only) 平顶形 (只用于固化)2) Ramp to Spike成斜坡直接升到峰值温度形3) Ramp / Soak有斜坡/浸润形The PCB, Components, Process and Assembly Materials effect the selection of the proper profile.根据PCB ，元件，制程和组装材料的影响选择正确的温度曲线.7.6.1 Top Hat Profile: 平顶曲线:The Top Hat is only used for cure of SMT adhesives and is the only profile shape approved for adhesive cure. This profile ramps at a moderate rate to a temperature window. See Table 2 for the cure windows for the materials used at Enics. At this point, the oven zones are used to stabilize the temperature and hold it in the cure window until the adhesive has a sufficient time to cure the adhesive (See Figure 8).平顶曲线只用于SMT胶固化并只有这种形状的曲线可以用于胶固化.曲线斜坡以缓慢速度上升到固化温度，表2是Enics所使用材料的固化温度，炉子的某些温区设定成稳定的温度使曲线保持在最低固化温度和最高固化温度之间让胶有充足的时间固化（图8）.Figure 8: Top Hat Cure Profile平顶固化曲线This stabilization is achieved by adjusting the conveyor speed and temperature zones in the oven. The length of this cure time is dependent on the material. Table 2 outlines the minimum cure times. If the PCB exceeds the maximum of the temperature window, there is some risk in causing a second reflow on the PCB and likewise shifted or missing component defects. Upon completion of the cure, the Top Hat profile uses a moderate negative ramp to room temperature.这种稳定性是通过调整链条速度和炉温温区来完成的.固化时间的长短是依赖材料. 表2描述了最小的固化时间. 假如PCB超过温度窗的最大温度, 那将导致第二次回流时PCB存在危险以及元件的移动或漏件. 在完成固化上, 从平顶温度下降到室温时使用中等的负温升斜率.SpecificationUnitsLoctite 3609Loctite 3616Loctite 3619Loctite 3621Max Positive Ramp RateC/Sec4.04.04.04.0Min. Cure TimeSec.90909090Max. Cure TimeSec.120120120120Min. Cure TemperatureC120140110140Max. Cure TemperatureC150170150150Max Negative Ramp RateC/Sec4.04.04.04.0Table 2: Adhesive Cure Parameters胶固化参数7.6.2 Ramp to Spike Profile: 成斜坡直接升到峰值的曲线:The ramp to spike is the preferred profile for Enics reflow soldering (See Figure 9). It has been well document that the ramp to spike profile applies more universally to fluxes chemistries and solder / PCB alloys. 回流焊接首选成斜坡直接升到峰值的曲线:（图9）这种曲线比较广泛地应用于各种助焊剂和焊锡/PCB合金.Figure 9: Ramp to Spike Profile成斜坡直接升到峰值This profile follows a moderate slope to a peak temperature into liquids (See Table 3 for material limits). Just prior to going into liquidus a slight dwell is targeted which will minimize the DT for the assembly improving soldering and maintaining below the specification for the materials (See Table 3). The slope will increase to a hit a peak temperature and then with an aggressive slope, decreased below liquidus. In some cases, it is necessary to flatten the peak temperature, or hold the temperature to achieve proper time above liquidus for sufficient wetting on larger thermal mass products however, the time above liquidus still needs to be maintained. Lastly, the profile should rapidly decrease within the limits of Table 3 the temperature below liquidus.这种曲线遵循一种均等的斜率到达峰值的 (看表格3的各种材料). 在即将进入液化之前的一个微小浸润, 是用于组装改善焊接和维护以下各种材料的规定为目标(看表格3). 增加斜率将到达一个峰值温度, 然后有一个陡峭的斜率, 减小液相线以下. 在某种情况下, 需要较大加热的批量生产产品中, 峰值温度需要变平整, 或者保持温度以达到在液相线以上有一段适当的时间去达到足够的浸润.最后曲线将迅速地下降在表格3温度极限液相线以下.SpecificationUnitsAlpha OM-5100Inventec SAC387-6DMax Positive Ramp RateC/Sec3.03.0Max. DTC1515Min. Time Above LiquidusSec.6030Max. Time Above LiquidusSec.12090Min. Peak TemperatureC210230Max. Peak Temperature (High Thermal Mass)C230250Max. Peak Temperature (Low Thermal Mass)C240260Min. Negative Ramp RateC/Sec00Max Negative Ramp RateC/Sec4.04.0Min. Rise SlopeC/Sec0.50.5Max Rise SlopeC/Sec22Min. Time To PeakSec.180200Max. Time To PeakSec.320360 Table 3: Ramp to Spike Profile Material Parameters7.6.3 Ramp / Soak Profile: 斜坡/浸润曲线：The ramp to soak profile should only be used with large thermal mass products, products with significant area array devices voiding, or products with significant differences in thermal mass (See Figure 10). This profile is used when the ramp to spike profile cannot achieve the DT specification stated in Table 4. In addition, some solder pastes will breakdown during the soak period causing poor soldering performance. Therefore, the soak time should be kept to a minimum to achieve the required DT should be maintained.Figure 10: Ramp Soak Profile斜坡/浸润曲线斜坡/浸润曲线应该是只使