Технология PCB - Производители PCB, OSP для обработки поверхности без свинца

печатная плата manufacturer, OSP for lead-free soldering surface treatment

In addition to the lead-free solder (Solder) must be completely lead-free, паяльная плита печатная плата surface (including various packages), для сварки кольца и ножек деталей, а также для других поверхностей также требуется отсутствие свинца. First, Я напишу на доске. It is expected that there will be seven or eight kinds of solderable treatments for mass production options. для тех, кто имеет доступ к Интернету для массового производства, it seems that only OSP and I-Sn or There are only two or three types of I-Ag.

обрабатывать свариваемую поверхность для пят или паяльников деталей, in addition to the early various IC metal tripods (LeadFrame, also known as lead frames), which are continuously electroplated with reel-to-reel (ReeltoReel), the rest of the bulk components (Discrets are separated) The formula is a poor translation) Regardless of whether it is passive or active, most of them adopt a large number of "barrelplating" (Barrelplating) processing methods. The current and future mainstream bath solutions will include:
1. Electroplating pure tin (with acidic tin sulfate TinSulfate or tin methane sulfonate as the bath, Он может использоваться для гальванизации станины или бочки. The surface tin plating of this kind of copper material can be divided into bright tin and matte tin. первые легко производят олово, while the latter is more expensive.)
2. Silverplating (mainly alkaline cyanide bath, гальваническое и роликовое покрытие станины.)
3. NickelandTinplating (Plating the surface of copper with a layer of nickel and then plating with pure tin will reduce the problem of tin whiskers.)
4. There are also electroplating of nickel and lithium (Ni/Pd), and electroplating of nickel and gold (Ni/Pd/Au), and even electroplating of various other tin alloys. Однако, due to the lack of two aspects of too expensive or insufficient technological maturity, Нынешние климатические изменения недостаточны для формирования климата и поэтому не могут быть введены в действие.

1. Organic flux OSP:
Simply put, OSP is to grow a layer of organic film on the clean bare copper surface to protect the copper surface in a normal environment from rusting (oxidation or sulfide, сорт.); but in the subsequent welding high temperature, Эта защитная пленка должна быть легко удалена и удалена флюсом, so that the exposed clean copper surface can be immediately combined with the molten solder to form a firm solder joint in a very short время. This can be protected Copper anti-rust organic film is called "OrganicSolderabilityPreservatives" (OrganicSolderabilityPreservatives).
In the early days, some types of coating containing rosins or active resins (Preflux) were formulated as the early products of this type of OSP. Однако, in the field of single-sided panels in the past, it was often called "full-surface treatment" (finishing the copper surface), which was a physical organic protective film coated on the copper surface; ) Chemicals, прямая реакция с медной поверхностью, образование "органического медного комплекса" химической защитной пленки. The principle is not exactly the same, но эффект медной защиты и сварки очень похож, so it is also called at present. OSP.
энтоне uses Azole chemicals (such as Benzo-Triazole) to protect the copper surface, это известный продукт в бизнесе. This is a temporary water-based copper protection agent from CU-56 that IBM first used that year. После многих лет опыта и улучшения, Такие поставщики внешних услуг добились значительного прогресса. It may become the main method of processing the board surface pad and the cheap and flat surface in the lead-free soldering era in the future.

The following will be introduced according to the five generations of the main chemicals used:
(1) Brenzotriazole (BTA), the first generation
This BTA protects the copper surface from corrosion and oxidation. It can be traced back to the temporary coating CU-56 (1% BTA aqueous solution) used by IBM to protect the copper surface in its печатная плата технология изготовления 60 - х годов 20 - го века. Enthone continued to study and improve, and became the well-known Entek processing method (Enthone Technology). даже до сих пор, there are still many industry players who only know the business name of Entek, но не учёба основателей BTA.

The reason why BTA can protect copper against corrosion is that it reacts immediately and directly with the cuprous oxide Cu20 on the surface of the copper material, and then generates a polymer-state organic copper complex salt (Complexor Tailu translated as complexing agent, It seems to be more clever than the one that quotes Japanese complexing agent), the following formula is the schematic structure of the reaction process, То есть, the imaginary diagram of the formation of multiple thin films on the copper surface. The film formed by these BTA and cuprous oxide (Cu20) is a bovine transparent and colorless film (turns brown after aging), в ванне станет толще, depending on temperature, time, pH, сорт. In 1989, тонквист и другие ученые опубликовали статью в журнале электрохимического общества, pointing out that when the BTA molecule first reacts with cuprous oxide, BTA will interact with its special orientation (orientation) of the "triple seat" in the molecule., And make it face outwards to form a long chain of [Cu(I)BTA)n. & другие механизмы адсорбции, a planar molecular film can be formed and attached to the copper surface.
ниже п. информационный журнал по сетевой доске, опубликованный в июне 1996 года. 80 for the textual explanation of the copper protection agent BTA:
The so-called BTA is the abbreviation of Benzotriazole, его официальное название - 1,2,3 - бензотриазол, which means that there are three interconnected azos at the 1, 2, and 3 positions and form a 5-carbon heterocyclic compound. Он называется "азотсодержащий амил" или золобензойное соединение.
BTA is a white, светло - жёлтый, безвкусный кристаллический порошок. Он очень устойчив в кислых и щелочных растворах, and it is not prone to oxidation and reduction reactions, Так что она довольно стабильна. It can form stable chemicals with metals. Этот BTA не растворимый в воде, but it can be dissolved in alcohols or benzene, обычно используется в качестве фотозащитной пленки или поглотителя ультрафиолетового излучения.
More than ten years ago, Enthone, a famous American supplier of circuit board chemicals, продается в растворах метанола и воды, как цветные и антиоксиданты на поверхности меди, and the trade name was ENTEKCU-55 and CU- 56. IBM подтвердил это. последний хорошо известен, and most of the domestic завод платы использовать 0.25% dilute aqueous solution as a copper protection agent. после окончания консистенции меди, плата погружается только в паз 30 - 60, которую можно обработать в течение нескольких секунд, and then dried with hot air to get a good protection effect. It can directly complete the image transfer work without brushing (either dry film or printing). Dilute sulfuric acid activation and cleaning before entering the secondary copper It can be easily removed, Это помогает склеивать и склеивать между медью и парчом.
Its high-concentration (l%) bath immersion treatment has stronger protection for bare copper, Он может заменить SMOBC, чтобы обеспечить долгосрочную медную защиту, и в процессе сборки лучше сварных свойств платы. процесс плавления, spraying, не так много валка олова. Эта статья - исследование IBM. Today, когда концепция "сокращения расточительства" становится все более широкой, стоимость платы Приходится снижать, the full text is hereby translated to read apricots as a reference for process improvement.