Kev ua tau zoo thiab tus cwj pwm ntawm OSP zaj duab xis hauv cov txheej txheem Lead-dawb ntawm PCB Luam Board

OSP (Organic Solderable Protective Film) raug suav hais tias yog cov txheej txheem kho saum npoo zoo tshaj plaws vim nws cov khoom zoo heev, txheej txheem yooj yim thiab tus nqi qis.

Nyob rau hauv daim ntawv no, thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS), thermogravimetric tsom (TGA) thiab photoelectron spectroscopy (XPS) yog siv los tshuaj xyuas cov yam ntxwv ntawm cov cua sov ntawm ib tiam tshiab ntawm kub resistant OSP films. Gas chromatography kuaj cov me me molecular organic Cheebtsam nyob rau hauv lub siab kub resistant OSP zaj duab xis (HTOSP) uas cuam tshuam rau solderability. Nyob rau tib lub sijhawm, nws qhia tau hais tias alkylbenzimidazole-HT nyob rau hauv lub siab kub resistant OSP zaj duab xis muaj tsawg heev volatility. Cov ntaub ntawv TGA qhia tau hais tias HTOSP zaj duab xis muaj qhov kub thiab txias ntau dua li cov qauv kev lag luam tam sim no OSP zaj duab xis. XPS cov ntaub ntawv qhia tau hais tias tom qab 5 lead-dawb reflows ntawm high-kub OSP, cov pa oxygen tsuas yog nce li ntawm 1%. Cov kev txhim kho saum toj no yog ncaj qha ntsig txog cov kev cai ntawm kev lag luam tsis muaj hlau lead-dawb solderability.

OSP zaj duab xis tau siv nyob rau hauv Circuit Court boards tau ntau xyoo. Nws yog organometallic polymer zaj duab xis tsim los ntawm cov tshuaj tiv thaiv ntawm azole tebchaw nrog kev hloov pauv hlau, xws li tooj liab thiab zinc. Ntau cov kev tshawb fawb [1,2,3] tau qhia txog kev tiv thaiv corrosion ntawm azole tebchaw ntawm cov hlau. GPBrown [3] ntse synthesized benzimidazole, tooj liab (II), zinc (II) thiab lwm yam kev hloov pauv hlau ntawm organometallic polymers, thiab piav qhia txog qhov kub thiab txias tsis kam ntawm poly (benzimidazole-zinc) los ntawm TGA yam ntxwv. GPBrown’s TGA cov ntaub ntawv qhia tau hais tias qhov degradation kub ntawm poly (benzimidazole-zinc) yog siab li 400 ° C nyob rau hauv cov huab cua thiab 500 ° C nyob rau hauv ib tug nitrogen cua, thaum lub degradation kub ntawm poly (benzimidazole-tooj ​​liab) tsuas yog 250 ° C. . Lub HTOSP zaj duab xis tsis ntev los no tau tsim los ntawm cov khoom siv tshuaj lom neeg ntawm poly (benzimidazole-zinc), uas muaj cov cua sov zoo tshaj plaws.

OSP zaj duab xis yog tsim los ntawm organometallic polymers thiab me me organic molecules entrained thaum lub sij hawm deposition txheej txheem, xws li fatty acids thiab azole tebchaw. Organometallic polymers muab qhov tsim nyog corrosion kuj, tooj liab nto adhesion, thiab nto hardness ntawm OSP. Qhov kub degradation ntawm organometallic polymer yuav tsum siab tshaj qhov melting point ntawm cov hlau lead-free solder kom tiv taus cov txheej txheem tsis muaj txhuas. Txwv tsis pub, OSP zaj duab xis yuav degrade tom qab ua tiav los ntawm cov txheej txheem tsis muaj txhuas. Qhov kub degradation ntawm OSP zaj duab xis feem ntau nyob ntawm qhov kub tsis kam ntawm organometallic polymer. Lwm qhov tseem ceeb uas cuam tshuam rau oxidation tsis kam ntawm tooj liab yog qhov tsis muaj zog ntawm azole tebchaw, xws li benzimidazole thiab phenylimidazole. Cov molecules me me ntawm OSP zaj duab xis yuav evaporate thaum lub sij hawm tsis muaj txhuas reflow txheej txheem, uas yuav cuam tshuam rau oxidation tsis kam ntawm tooj liab. Gas chromatography-mass spectrometry (GC-MS), thermogravimetric tsom (TGA) thiab photoelectron spectroscopy (XPS) tuaj yeem siv los piav qhia txog kev kub ntxhov ntawm OSP.

1. Gas chromatography-mass spectrometry tsom xam

Cov phaj tooj liab kuaj tau coated nrog: a) HTOSP zaj duab xis tshiab; b) kev lag luam tus qauv OSP zaj duab xis; thiab c) lwm qhov kev lag luam OSP zaj duab xis. Scrape txog 0.74-0.79 mg ntawm OSP zaj duab xis los ntawm cov phaj tooj liab. Cov coated tooj liab daim hlau no thiab cov qauv scraped tsis tau txais kev kho mob rov qab. Qhov kev sim no siv H / P6890GC / MS ntsuas, thiab siv cov koob txhaj tshuaj tsis muaj koob txhaj tshuaj. syringe-free syringes tuaj yeem ncaj qha desorb cov qauv hauv cov qauv chav. Lub syringe yam tsis muaj syringe tuaj yeem hloov cov qauv hauv lub khob me me rau hauv qhov nkag ntawm cov roj chromatograph. Cov pa roj carbon monoxide tuaj yeem txuas ntxiv nqa cov organic sib txuas mus rau cov roj chromatograph kem rau kev sau thiab sib cais. Muab cov qauv tso ze rau sab saum toj ntawm kem kom thermal desorption tuaj yeem rov ua haujlwm zoo. Tom qab cov qauv txaus tau desorbed, cov roj chromatography pib ua haujlwm. Hauv qhov kev sim no, RestekRT-1 (0.25mmid × 30m, zaj duab xis tuab ntawm 1.0μm) roj chromatography kem tau siv. Qhov kub nce qhov kev pab cuam ntawm cov roj chromatography kem: Tom qab cua sov ntawm 35 ° C rau 2 feeb, qhov kub pib nce mus rau 325 ° C, thiab cua kub yog 15 ° C / min. Cov txheej txheem thermal desorption yog: tom qab cua sov ntawm 250 ° C rau 2 feeb. Qhov loj / nqi piv ntawm cov sib cais volatile organic tebchaw yog kuaj pom los ntawm huab hwm coj spectrometry nyob rau hauv thaj tsam ntawm 10-700daltons. Lub sijhawm khaws cia ntawm tag nrho cov organic molecules me me kuj raug kaw.

2. Thermogravimetric analysis (TGA)

Ib yam li ntawd, HTOSP zaj duab xis tshiab, kev lag luam tus qauv OSP zaj duab xis, thiab lwm yam OSP zaj duab xis tau coated ntawm cov qauv. Kwv yees li ntawm 17.0 mg ntawm OSP zaj duab xis tau muab pov tseg los ntawm cov phaj tooj liab raws li cov khoom siv kuaj. Ua ntej qhov kev xeem TGA, tsis yog cov qauv lossis cov yeeb yaj kiab tuaj yeem raug kev kho mob tsis muaj hlau lead. Siv TA Instruments ‘2950TA los ua TGA xeem nyob rau hauv kev tiv thaiv nitrogen. Kev ua haujlwm kub tau khaws cia hauv chav sov li 15 feeb, thiab tom qab ntawd nce mus rau 700 ° C ntawm tus nqi ntawm 10 ° C / min.

3. Photoelectron spectroscopy (XPS)

Photoelectron Spectroscopy (XPS), tseem hu ua Chemical Analysis Electron Spectroscopy (ESCA), yog ib txoj hauv kev tshuaj xyuas qhov chaw. XPS tuaj yeem ntsuas 10nm tshuaj muaj pes tsawg leeg ntawm txheej txheej. Txheej HTOSP zaj duab xis thiab kev lag luam tus qauv OSP zaj duab xis ntawm lub phaj tooj liab, thiab tom qab ntawd mus dhau 5 cov hlau lead-dawb reflows. XPS tau siv los txheeb xyuas HTOSP zaj duab xis ua ntej thiab tom qab kev kho mob rov qab. Kev lag luam-tus qauv OSP zaj duab xis tom qab 5 cov hlau lead-dawb reflow kuj tau txheeb xyuas los ntawm XPS. Cov cuab yeej siv yog VGESCALABMarkII.

4. Los ntawm qhov kev xeem solderability

Siv solderability test boards (STVs) rau kev xeem dhau-qhov solderability. Muaj tag nrho ntawm 10 lub rooj tsav xwm kev xeem STV arrays (txhua qhov array muaj 4 STVs) coated nrog cov yeeb yaj kiab thickness txog 0.35μm, ntawm 5 STV arrays yog coated nrog HTOSP zaj duab xis, thiab lwm 5 STV arrays yog coated nrog kev lag luam tus qauv. OSP film. Tom qab ntawd, cov coated STVs tau dhau los ua cov kub kub, tsis muaj hlau lead-dawb reflow kev kho mob nyob rau hauv solder paste reflow qhov cub. Txhua qhov kev xeem muaj xws li 0, 1, 3, 5 lossis 7 sib law liag reflows. Muaj 4 STVs rau txhua hom yeeb yaj kiab rau txhua qhov kev xeem rov qab. Tom qab cov txheej txheem reflow, tag nrho cov STVs tau ua tiav rau qhov kub thiab txias thiab tsis muaj hlau lead-dawb yoj soldering. Los ntawm-qhov solderability tuaj yeem txiav txim siab los ntawm kev tshuaj xyuas txhua STV thiab suav cov naj npawb ntawm qhov raug sau los ntawm qhov. Qhov kev lees paub los ntawm lub qhov yog tias cov khoom siv tag nrho yuav tsum tau ntim rau saum lub plated los ntawm lub qhov lossis lub ntug sab saud ntawm lub qhov.