J-STD-020D
Moisture/Reflow Sensitivity Classification for Nonhermetic Solid State Surface Mount Devices
非密封固态表面贴装元件湿度/回流焊敏感度分级
1 PURPOSE(目的）
The purpose of this standard is to identify the classification level of nonhermetic solid state surface mount devices (SMDs) that are sensitive to moisture-induced stress so that they can be properly packaged, stored, and handled to avoid damage during assembly solder reflow attachment and/or repair operations.
本标准旨在识别非密封固态表面贴装元件的湿度敏感等级以便其能合适的封装，储存，作业以避免在回流和维修作业中被损伤. This standard may be used to determine what classification/preconditioning level should be used for SMD package qualification. Passing the criteria in this test method is not sufficient by itself to provide assurance of long-term reliability
本标准用于判定合格的SMT封装应使用何种等级/预处理水平.依据本测试方法且通过对应判定标准的元件并不能保证其长期可靠性
1.1 Scope（范围）
This classification procedure applies to all nonhermetic solid state Surface Mount Devices (SMDs) in packages, which, because of absorbed moisture, could be sensitive to damage during solder reflow. The term SMD as used in this document means plastic encapsulated surface mount packages and other packages made with moisture-permeable materials. The categories are intended to be used by SMD producers to inform users (board assembly operations) of the level of moisture sensitivity of their product devices, and by board assembly operations to ensure that proper handling precautions are applied to moisture/reflow sensitive devices. If no major changes have been made to a previously qualified SMD package, this method may be used for reclassification according to 4.2.
此分类程序适用于所有非密封固体表面贴装元件，此部分元件由于吸收湿气而在回流焊接中容易损伤. 本文件所提及的术语“SMD”指的是塑封或本体为吸湿材料的元件.分类的目的是为了让元件制造商能告知元件使用者（PCBA组装）其产品的湿敏等级，确保元件使用者能恰当作业，如果对之前认证过的SMD封装没有重大更改，依据4.2此方法亦可用于元件的再次分类.
This standard cannot address all of the possible component, board assembly and product design combinations. However, the standard does provide a test method and criteria for commonly used tech
nologies. Where uncommon or specialized components or technologies are necessary, the development should include customer/manufacturer involvement and the criteria should include an agreed definition of product acceptance.
此标准不能涵盖所有与设计，组装相关联的元件.但是，此标准为通用技术提供了一个测试方法和标准. 如果使用特殊技术或特殊元件，则需客户以及相关的制造方定义一个双方同意的产品接受标准.
SMD packages classified to a given moisture sensitivity level by using Procedures or Criteria defined within any previous version of
J-STD-020, JESD22-A112 (rescinded), or IPC-SM-786 (rescinded) do not need to be revision unless a change in classification level or a higher peak classification temperature is desired. Annex B provides an overview of major changes from Revision C to Revision D of this document.
在使用之前版本J-STD-020，JESD22-A112（已作废），IPC-SM-786（已作废）标准中已分级的湿敏元件除非敏感等级变更或耐温峰值提高，否则无须重新分级.附件B提供了版本C升级到版本D的主要变更.include中文
Note: If the procedures in this document are used on packaged devices that are not included in this sp
ecification’s scope, the fail ure criteria for such packages must be agreed upon by the device supplier and their end user
备注：当封装元件未在本标准规格范围内，如需使用此文件中的流程判定，则不良标准需元件供应商和其客户同意.
1.2 Background（背景）
The vapor pressure of moisture inside a nonhermetic package increases greatly when the package is exposed to the high temperature of solder reflow. Under certain conditions, this pressure can cause internal delamination of the packaging materials from the die and/or leadframe/substrate, internal cracks that do not extend to the outside of the package, bond damage, wire necking, bond lifting, die lifting, thin film cracking, or cratering beneath the bonds. In the most severe case, the stress can result in external package cracks. This is
commonly referred to as the ‘‘popcorn’’ phenomenon because the internal stress causes the package to bulge and then crack wit h an audible ‘‘pop.’’ SMDs are more susceptible to this problem than through-hole parts because they are exposed to higher temperatures during reflow soldering. The reason for this is that the soldering operation must occur on the same side of the board as the SMD de
vice. For wave-soldered through-hole devices, the soldering operation occurs under the board that shields the devices from the hot solder through-hole devices, the soldering operation occurs under the board that shields the devices from the hot solder Throughhole devices that are soldered using intrusive soldering or ‘‘pin in paste’’ processes may experience the same type of moisture-induced failures as SMT devices.
非密封元件封装在回流高温条件下，其内部水蒸气压力猛增.在某一件下，压力将导致封装从内部分层或者内裂，邦定受损。更为严重的情况下，压力将导致外部封装开裂.此称之为“爆米花”现象，即由于内部压力引起封装膨胀并且伴随“砰，砰”声而裂开. 相对于通孔元件，由于SMD元件需更高的温度回流，因此此种情况尤为敏感.其原因为，SMT元件在PCB同一面回流因而受热更多。而对于通孔元件，其通常在在PCB之上，因而避免直接高温。如使用印刷回流制程的通孔元件则可能与出现SMD元件一样失效.
1.3 Terms and Definitions(术语与定义）
accelerated equivalent soak –A soak at a higher temperature for a shorter time (compared to the standard soak), to provide roughly the same amount of moisture absorption. See also soak
快速浸泡：相对标准浸泡而言，使用更高温度在更短时间内浸泡
acoustic microscope –Equipment that creates an image using ultrasound to view a specimen’s surface or subsurface features, including defects and damage. See J-STD-035 for more information.
声学显微镜：使用超声波对元件表面和内部特征（包括不良和损伤）进行查看并产生图像的设备
area array package –A package that has terminations arranged in a grid on the bottom of the package and contained within the package outline.
classification temperature (Tc) –The maximum body temperature at which the component manufacturer guarantees the component MSL as noted on the caution and/or bar code label per J-STD-033
依据J-STD-033元件制造商在警告标签物料标签上所标示的元件本体最高耐温.
crack –A separation within a bulk material. See also Delamination
开裂：元件内部分离
damage response –All irreversible changes caused by exposure to a reflow soldering profile.
损伤反应：由回流引起的所有不可逆的的改变.
dead-bug (orientation) –The orientation of the package with the terminals facing up.元件封装术语：元件引脚朝上的封装（如下图1）
. delamination –An interfacial separation between two materials intended to be bonded. See also crack
分层：两种物料结合部位的分离，参考裂开
downbond area –An area for a wire bond on the die paddle, whose dimensions equal those of a single bond pad on the die.
floor life –The allowable time period after removal from a moisture barrier bag, dry storage or dry bake and before the solder reflow process.
车间寿命：元件从从防潮袋，干燥箱，或烘烤后取出到回流之间允许的时间
full body hot air rework –The process of heating a package by directing heated gas at the package body in order to melt only that package’s solder connections.
本体热风返工：使用热风直接给整个元件本体加热而使元件焊点融化的过程
live-bug (orientation) –The orientation of the package when resting on its terminals
封装术语：元件引脚朝下的的封装
manufacturer’s exposure time (MET) –The maximum cumulative time after bake that components may be exposed to ambient conditions prior to shipment to the end user.
制造商暴露时间：元件烘烤后，在运送给终端使用者之前，元件暴露在周边环境中最大允许时间.
moisture/reflow sensitivity classification –The characterization of a component’s susceptibility to damage due to absorbed moisture when subjected to reflow soldering.
湿度/回流敏感分类：元件由于吸收湿气在回流条件下受损的敏感特性
moisture sensitivity level (MSL) –A rating indicating a component’s susceptibility to damage due to absorbed moisture when subjected to reflow soldering
湿敏等级：对于元件吸湿在回流条件下受损敏感性的分级
package thickness –The component thickness excluding external terminals (balls, bumps, lands, leads) and/or nonintegral heat sinks
封装厚度：元件除去外部插座，引脚，焊盘，散热片等的厚度
peak package body temperature (Tp) –The highest temperature that an individual package body reaches during MSL classification.
元件本体最高温度：在MSL分类中所规定的元件本体最高能承受的温度.
reclassification –The process of assigning a new moisture sensitivity level to a previously classified device.
重新分类：对之前已分类的元件重新指定新的湿敏等级
soak –The exposure of a component for a specified time at a specified temperature and humidity. See also accelerated equivalent soak.
浸泡：在特定的温度和湿度下，元件在特定的时间内暴露.
3 APPARATUS(设备）3.1 Temperature Humidity Chambers Moisture chamber(s), capable of operating at 85 °C/85% RH, 85 °C/60% RH, 60 °C/60% RH, and 30 °C/60% RH. Within the chamber working area, temperature tolerance must be ± 2 °C and the RH tolerance must be ± 3% RH.
恒温恒湿箱：需满足85 °C/85% RH, 85 °C/60% RH, 60 °C/60% RH, and 30 °C/60% RH操作要求，且在箱内工作区域温度误差必须± 2 °C，湿度误差3% RH.
3.2.1 Full Convection (Preferred) Full convection reflow system capable of maintaining the reflow profiles required by this standard
全对流
3.2.2 Infrared Infrared (IR)/convection solder reflow equipment capable of maintaining the reflow profiles required by this standard. It is required that this equipment use IR to heat only the air and not directly impinge upon the SMD Packages/ devices under test.
红外回流
3.3 Ovens Bake oven capable of operating at 125 +5/-0 °C.烤箱（能满足125 +5/-0 °C）
3.4 Microscopes（显微镜）
3.4.1 Optical Microscope Optical Microscope (40X for external and 100X for cross-section exam, higher magnification might be required for verification).
光学显微镜：（40倍用于外部检查，100倍用于切片检查）验证中可能要求更高倍数显微镜.
3.4.2 Acoustic Microscope Typically a scanning acoustic microscope with C-Mode and Through Transmission capability. It should be capable of measuring a minimum delamination of 5% of the area being evaluated
声波扫描显微镜：具备C-Modec穿透功能，且能量测评估区域最小5%的分层的能力.
3.5 Cross-Sectioning Microsectioning equipment as recommended per IPC-TM-650, Methods 2.1.1 and 2.1.1.2, or other applicable document
切片：建议采用IPC-TM-650, Methods 2.1.1 and 2.1.1.2, 或其它推荐适用的设备
3.6 Electrical Test Electrical test equipment with capabilities to perform appropriate testing on devices.
电气测试：能合适的测试元件
3.7 Weighing Apparatus (Optional) Apparatus capable of weighing the package to a resolution of 1 microgram. This apparatus must be maintained in a draft-free environment, such as a cabinet. It is used to obtain absorption and desorption data on the devices under test (see Clause 8).
称重仪（可选）：此设备须精度1微克，且放置在无温漂环境下。此设备用于获取元件吸收和解析数据.
3.8 Beaded Thermocouple Temperature Measurement Refer to JEP140 for guidance on procedures to accurately and consistently measure the temperature of components during exposure to thermal excursions. JEP140 guideline applications can include, but is not limited to, temperature profile measurement in reliability test chambers and solder reflow operations that are associated with component assembly to printed wiring boards (PWBs).
4 CLASSIFICATION/RECLASSIFICATION(分类/重新分类）
Refer to 4.2 for guidance on reclassification of previously qualified/classified SMDs
对于之前已认证分类的SMD元件请参考4.2重新分级
Engineering studies have shown that thin, small volume SMD packages reach higher body temperatures during reflow soldering to boards that have been profiled for larger packages. Therefore,
technical and/or business issues normally require thin, small volume SMD packages (reference Tables 4-1 and 4-2) to be classified at higher reflow temperatures. To accurately measure actual peak package body temperatures refer to JEP140 for recommended thermocouple use.
研究表明相对于大封装元件，薄的，小体积的封装在同样的温度曲线下元件本体温度更高.因此，细小封装的元件划分到回流温度较高的一类（参考如下4-1,4-2列表）.为精确的测出元件本体实际最高峰温度，请参考JEP140推荐的电热偶
Note 1: Previously classified SMDs should only be reclassified by the manufacturer. Users should refer to the ‘‘Moisture Sensitivity’’ label on the bag to determine at which reflow temperature the SMD packages were classified.
备注1：之前已分级的SMD元件只能由元件制造商重新分级.元件使用者应该参考包装袋上的“湿敏”标签确定回流温度
Note 2: Unless labeled otherwise, level 1 SMD packages are considered to be classified at 220 °C.
除非标签已注明，否则Level1的SMD元件默认为220度
Note 3: If supplier and user agree, components can be classified at temperatures other than those in T
ables 4-1 and 4-2.
如供方与使用方已达成一致，则元件温度分级可以不采用4-1和4-2的温度
Table 4-1 SnPb Eutectic Process - Classification Temperatures (Tc)（有铅制程-温度分级）
Table 4-2 Pb-Free Process - Classification Temperatures (Tc)（无铅制程-温度分级）
Note 1: At the discretion of the device manufacturer, but not the board assembler/user, the maximum peak package body temperature (Tp) can exceed the values specified in Tables 4-1 or 4-2. The use of a higher Tp does not change the classification temperature (Tc).
Note 2: Package volume excludes external terminals (e.g., balls, bumps, lands, leads) and/or nonintegral heat sinks
元件体积不包括外部引脚以及非组合的散热片等
Note 3: The maximum component temperature reached during reflow depends on package thickness and volume. The use of convection
reflow processes reduces the thermal gradients between packages. However, thermal gradients due to differences in thermal mass of SMD packages may still exist.
回流过程中元件最高本体温度取决于其厚度和体积.虽然采用热风对流回焊可以减少这种由于封装不同而导致的温度差异. 但是这种差异依然存在.
Note 4: Moisture sensitivity levels of components intended for use in a Pb-free assembly process shall be evaluated using the Pb-free classification temperatures and profiles defined in Tables 4.2 and 5-2, whether or not Pb-free.
用于无铅制程的元件，无论其本身是有铅还是无铅，应使用列表4.2和5-2中所定义的无铅温度和曲线进行评估
Note 5: SMD packages classified to a given moisture sensitivity level by using Procedures or Criteria defined within any previous version of J-STD-020, JESD22-A112 (rescinded), IPC-SM-786 (rescinded)
do not need to be reclassified to the current revision unless a change in classification level or a higher peak classification temperature is desired.
除非等级更改或者提高峰值问题，否则依据之前J-STD-020, JESD22-A112 (rescinded), IPC-SM-786已分级的元件无须依据本版本重新分级
4.1 Compatibility with Pb-Free Assembly Rework Pb-free area array components (classified per Table 4.2) should be capable of assembly rework at 260 °C within 8 hours of removal from dry storage or bake, per J-STD-033. Components that do not meet this assembly rework requirement or that the supplier does not support 260 °C rework t shall be so specified by the component manufacturer. To verify this capability for components classified at a temperature below 260 °C , a sample of the size per
5.1.2 shall be soaked per level 6 conditions (see Table 5-1) using a time on label (TOL) of 8 hours, and subjected to a single reflow cycle with Tp of not less than 260 °C. All devices in the sample shall pass electrical test and have a damage response (per
6.1 and 6.2) not greater than that observed for the same package at its rated MSL level. Rework compatibility verification is not required for area array components rated at 260 °C or peripheral leaded
metal lead frame packages that do not require full body hot air rework.
无铅返工兼容：依据J-STD-033，列表4.2中元件从干燥或烘烤取出后应能在260度，8小时之内完成重工。如果元件无法满足此返工要求或者无法使用260度重工，则此元件应由制造商特殊标明.
4.2 Reclassification SMD packages previously classified to a moisture sensitivity level and classification temperature (Tc) may be reclassified if the damage response (e.g., delamination/cracking) at the more severe condition for items listed in 6.1v and 6.2 is less than, or equal to, the damage response at the original classification condition. If no major changes have been made to a previously qualified SMD package, this method may be used for reclassification to an improved level (i.e., longer floor life) at the same reflow temperature. The reclassification level cannot be improved by more than 1 level without additional reliability testing. Reclassification to level 1 requires additional reliability testing. If no major changes have been made to a previously qualified SMD package, this method may be used for reclassification at a higher reflow temperature providing the moisture level remains the same or degrades to a more sensitive level. No SMD packages classified as moisture sensitive by any previous version of J-STD-020, JESD22-A112 (rescinded), or
IPC-SM-786 (rescinded) may be reclassified as nonmoisture sensitive (level 1) without additional reliability stress testing
(e.g., JESD22-A113 and JESD-47 or the semiconductor manufacturer’s in-house procedures).
To minimize testing, the results from a given SMD package may be generically accepted to cover all other devices which
are manufactured in the same package, using the same packaging materials (e.g., die attach, mold compound and/or die
coating, etc.), with the die using the same wafer fabrication technology, and with die pad dimensions not greater than those
qualified.
The following attributes could affect the moisture sensitivity of a device and may require reclassification:
• Die attach material/process.
• Number of pins.
• Encapsulation (mold compound or glob top) material/process.
• Die pad area and shape.
• Body size.