Nzira yekudzivirira circuit board warping

1, Nei wedunhu bhodhi inofanirwa kuve yakati sandarara

Pane otomatiki yekuisa mutsara, kana iyo yakadhindwa bhodhi isiri yakati sandara, inokonzeresa kusarongeka kumisikidza, zvikamu hazvigone kuiswa mumakomba uye pamusoro pekusimudza mapedhi ebhodhi, uye kunyange kukanganisa iyo otomatiki yekuisa muchina. Bhodhi rakaiswa nezvikamu rakakotama mushure mekushuvira, uye tsoka dzezvinhu dzakaoma kutema zvakapfava uye zvakashambidzika. Iyo bhodhi haigone kuiswa pane chassis kana iyo soketi mumushini, saka zvakare zvinonetsa kwazvo kune iyo fekitori yegungano kusangana neiyo bhodhi inowira. Parizvino, akadhindwa mabhodhi apinda munguva yekumisikidzwa kwepasi uye kuiswa kwechip, uye magungano emisangano anofanira kuve nezvinodiwa zvakanyanya zvebhodhi inokamura.

2, Standard uye bvunzo nzira ye warpage

Sekureva kweAmerican ipc-6012 (1996 edition) <<kuzivikanwa uye Performance Tsananguro yemabhodhi akasimba akadhindwa>>, iyo yepamusoro inobvumidzwa warpage uye kukanganisa kwemahombekombe akadhirowewa pamusoro ndeye 0.75%, uye 1.5% yemamwe mabhodhi. Izvi zvinovandudza zvinodikanwa zvepamusoro zvakasungirirwa mabhodhi akadhindwa achienzaniswa ne ipc-rb-276 (1992 edition). Parizvino, iyo inobvumidzwa warpage yeyese yemagetsi gungano fekitori, ingave mbiri-mativi kana akawanda-masenduru, iri 1.6mm gobvu, kazhinji 0.70 ~ 0.75%. Kune mazhinji SMT neBGA mabhodhi, inofanirwa kuve 0.5%. Mamwe mafekitori emagetsi ari kukurudzira kukwidziridza mwero wewarpage kusvika pa0.3%. Maitiro ekuyedza warpage anoteera gb4677.5-84 kana ipc-tm-650.2.4.22b. Isa bhodhi rakadhindwa papuratifomu yakasimbiswa, isa yero yekuyedza munzvimbo ine warpage yakakura, uye ugovane hupamhi hwesiyero yekuyedza nehurefu hwemucheto wakakombama webhodhi rakadhindwa kuti uverenge warpage yebhodhi rakadhindwa.

3, Anti warping ndiro panguva mukugadzira

1.Uinjiniya dhizaini: matanho muPCB Dhizaini:

A. Kurongeka kwemashizha akapora pakati pezvikamu zvichave zvakaenzana. Semuyenzaniso, pakukora pakati akaturikidzana 1 ~ 2 uye 5 ~ 6 matanhatu akaturikidzana anofanira kunoenderana uwandu Semi akarapwa machira, zvikasadaro zviri nyore kuti mutswe pashure lamination.

B. Zvigadzirwa zvemutengesi mumwechete zvinoshandisirwa multilayer yepakati bhodhi uye semi yakaporeswa jira.

C. Nzvimbo yemutsara patani pamusoro pevhu uye pamusoro peB rekunze kwekumusoro rinofanira kunge riri padhuze sezvinobvira. Kana pamusoro a pane hombe yemhangura pamusoro uye pamusoro peB zvinotora waya shomanana, bhodhi rakadhindwa riri nyore kuruka mushure mekucheka. Kana iwo mutsara wenzvimbo musiyano uripo pakati pemativi maviri wakanyanya kukura, mamwe ma grid akazvimirira anokwanisa kuwedzerwa padivi rekushomeka pachiyero.

2. Kuomesa ndiro usati wavhara:

Chinangwa chekuomesa mhangura yakapfekedzwa laminate usati wavhara (150 ° C, nguva 8 ± 2 maawa) kubvisa hunyoro mundiro, kusimbisa zvakakwana resini mundiro uyezve kubvisa kusara kwekushushikana mundiro, izvo zvinobatsira kudzivirira ndiro warpage. Parizvino, mazhinji-maviri mativi uye multilayer mabhodhi achiri kuomerera padanho rekuomesa pamberi kana mushure mekuvhara. Nekudaro, pane izvo zvinosarudzika mune mamwe mafekitori eplate. Parizvino, iyo yekuomesa nguva mirau yepcb mafekitori zvakare isingaenderane, kubva maawa mana kusvika gumi. Zvinokurudzirwa kusarudza zvinoenderana negiredhi remapuranga akadhindwa akagadzirwa uye zvinodiwa nevatengi zvewarpage. Maitiro ese ari maviri anokwanisika. Inokurudzirwa kuomesa bhodhi mushure mekucheka. Ndiro yemukati ichaomeswawo.

3.Kureba uye latitude yesemi yakaporeswa jira:

Iyo yakarukwa uye weft shrinkage ye semi yakaporeswa jira mushure mekumisikidza zvakasiyana, saka iyo warp uye weft inofanirwa kusiyaniswa panguva yekuvhara uye kumomesa. Zvikasadaro, zviri nyore kukonzera iyo warpage yeiyo yapera ndiro mushure mekumomesa, uye zvinonetsa kugadzirisa kunyangwe iko kumanikidza kunoiswa kuomesa ndiro. Zvikonzero zvakawanda zveiyo warpage yemazhinji multilayer board anokonzereswa nekusanzwisisika kwematanho uye latitude yemasikati akapora machira panguva yekukwirisa.

Nzira yekusiyanisa pakati pehurefu uye nharaunda? Iwo anotenderedza mafambiro eiyo yakakungurutswa semi yakaporeswa pepa ndiyo yekumonera mafambiro, uye hupamhi hwekutungamira ndiyo weft nzira. Nezve mhangura foil, iyo yakareba divi iri mune weft nzira, uye ipfupi divi iri mune yakarukwa nzira. Kana usina chokwadi, unogona kutarisa nemugadziri kana mutengesi.

4. Kushushikana kwekushushikana mushure mekudzora:

Mushure mekupisa kupisa uye kutonhora kudzvanya, tora iyo multilayer bhodhi, cheka kana chigayo ubure burr, uye wozoiisa yakati sandara muchoto pa150 ℃ kwemaawa mana, kuti zvishoma nezvishoma kuburitsa kushushikana mubhodhi uye kurapa zvakakwana iyo resin . Iyi nhanho haigone kusiiwa.

5. Iyo jira rinoda kutwasanudzwa panguva yeelectroplating:

Kana 0.4 ~ 0.6mm Ultra-yakatetepa multilayer bhodhi inoshandiswa kune ndiro pamusoro electroplating uye pateni electroplating, yakakosha pini rollers ichaitwa. Mushure mekukochekera mahwendefa matete pabhawa inobhururuka pane otomatiki electroplating tambo, shandisa tambo yakatenderedza kusunga tambo dzepini pabhawa rese rinobhururuka, kuitira kururamisa mahwendefa ese pane roller, kuitira kuti mahwendefa akafukidzwa asazoremara. Pasina chiyero ichi, ndiro yakatetepa ichakotama mushure mekusanganisa huta hwemhangura hwemakumi maviri kana makumi matatu emamirioni, uye zvinonetsa kugadzirisa.

6.Kutonhora kweplate mushure mekupisa kwemhepo mweya.

Kana iro rakadhindwa bhodhi rikaenzaniswa nemhepo inopisa, inokanganiswa nekupisa kwakanyanya kweiyo solder yekugezera (ingangoita 250 ℃), uyezve inozoiswa pane yakatsetseka marble kana ndiro yesimbi yekutonhora kwechisikigo, uye ndokutumirwa kune post processor yekuchenesa. Izvi zvakanaka kune anti warping yebhodhi. Nekuda kwekusimudzira kupenya kwetiyini tini pamusoro, mamwe mafekitori anoisa mahwendefa mumvura inotonhorera pakarepo mushure mekushisa kwemhepo inopisa, uye oenda nawo kunze kwekurapwa mushure memasekonzi mashoma. Uku kupisa kumwe uye kumwe kutonhora kukanganisa kunogona kuburitsa warpage, delamination kana blistering pane mamwe marudzi emaplate. Mukuwedzera, mubhedha unofamba-famba unogona kuiswa pamidziyo yekutonhora.

7.Kurapa kwepaipi yekumonera:

Mune fekitori inochengetedzwa zvakanaka, 100% flatness kuongorora kunoitwa panguva yekupedzisira kuongorora kwemabhodhi akadhindwa. Mabhodhi ese asina kukwana anozotorwa, oiswa muchoto, akaomeswa pa150 ℃ uye pasi pesimba rinorema kwema3 ~ 6 maawa, uye ndokutonhora zvakasununguka pasi pekuremerwa kwakanyanya. Wobva waburitsa bhodhi mushure mekumanikidzwa kumanikidzwa uye tarisa kumeso. Nenzira iyi, mamwe mabhodhi anogona kuchengetedzwa. Mamwe mabhodhi anoda kuomeswa nekutsimbirirwa kaviri kana katatu kuti aenzaniswe. Iyo pneumatic ndiro inokamhina uye yakatwasuka muchina inomiririrwa neShanghai Huabao yanga ichishandiswa neShanghai Bell kugadzirisa iyo warpage yedunhu bhodhi. Kana matanho ekumusoro ekurwisa kurwisa asingaitwe, mamwe mabhodhi haana basa uye anogona kungobviswa.