I-Semiconductor PCB Materials: Umhlahlandlela Wokukhetha Wobuchwepheshe

Isingeniso

Izinto ze-PCB ze-semiconductor zibhekana nezidingo ezingajwayelekile ekudluliselweni kwe-RF, umzila wesiginali onesivinini esikhulu, ukuphathwa kwamandla, kanye nezimo zokushisa eziphakeme. I-substrate inquma ngokuqondile ubuqotho besignali, ukusebenza okushisayo, nokuthembeka komhlangano.

Lo mhlahlandlela uhlola izinto ze-semiconductor PCB ngamalensi amathathu abalulekile: izigaba zezinto kanye nezakhiwo zazo zomzimba, izinkomba zokusebenza ezibalulekile eziqhuba ukukhethwa kwezinto, kanye nezinhlaka zezinqumo ezisebenzayo zokufanisa izinto nezinhlelo zokusebenza ezithile.

Kungani I-Semiconductor PCB Materials Ibalulekile

Amapharamitha Wokusebenza Kagesi

I-dielectric constant (Dk) kanye ne-dissipation factor (Df) ilawula ngokuyisisekelo ikhwalithi yokudlulisela isignali ezintweni ze-semiconductor PCB. Amanani aphansi ka-Dok anciphisa ukubambezeleka kokusabalalisa isignali futhi anciphise ukuhluka kokuphazamiseka, kuyilapho i-Df ephansi ihlobana ngokuqondile nokulahlekelwa kokufakwa okuncishisiwe kumaza aphezulu. I-Tangent yokulahlekelwa iba bucayi ngaphezu kuka-10 GHz, lapho nokuhluka okuncane kwempahla kubangela amaphutha esigaba esilinganisekayo.

Izidingo Zokulawula Okushisayo

I-Thermal conductivity inquma ukusebenza kahle kokukhipha ukushisa kusuka ezingxenyeni ezisebenzayo kuya kuma-heatsink angaphandle noma emoyeni ozungezile. I-coefficient of thermal expansion (CTE) ukungafani phakathi kwezinto ze-semiconductor PCB kanye ne-silicon iyafa kudala ingcindezi yomshini ngesikhathi sokuhamba ngebhayisikili. Lokhu kucindezeleka kugxila emajoyini e-solder nama-wire bond, okusheshisa ukwehluleka kokukhathala. Izinto ezinamavelu e-CTE eduze ne-silicon (cishe u-2.6 ppm/°C) zibonisa ukwethembeka okuphakeme kwesikhathi eside.

Izidingo ze-Substrate yokupakisha

Ama-substrate okupakisha e-semiconductor abeka izidingo eziqinile kune-PCB ezivamile. Ububanzi bomugqa obungaphansi kwama-micrometer angu-25, ukubekezelelana kokubhaliswa kwesendlalelo kuya kwesendlalelo ngaphansi kwama-micrometer angu-15, kanye nemijikelezo eminingi yokushintshashintsha kwezinga lokushisa ephezulu kudinga izinto ezinokuqina okumangalisayo. Amazinga okushisa okuguquka kwengilazi adlula u-170°C avimbela ukugoba kanye nokwehlukaniswa ngesikhathi sezinqubo zokuhlanganisa ezingenalo i-lead ezifinyelela ku-260°C.

Izinhlobo Zezinto Ze-PCB Semiconductor

I-High-Tg FR-4 kanye ne-Modified Epoxy Laminates

Izinhlobonhlobo ze-High-Tg FR-4 zinikeza amazinga okushisa okushintsha kwengilazi phakathi kuka-170°C no-180°C uma kuqhathaniswa nobubanzi obujwayelekile be-FR-4's 130-140°C. Lezi zinto ze-PCB ze-semiconductor zigcina ukuzinza kwe-dimensional ngokusebenzisa amaphrofayili okugeleza angenawo umthofu. Ama-Dielectric constants ngokuvamile asukela ku-4.2 kuye ku-4.6 ku-1 MHz, anezici zokulahla azungeze u-0.020.

Ibiza kakhulu kumasekhethi edijithali asebenza ngaphansi kuka-1 GHz, i-high-Tg FR-4 ifanela amabhodi okuphakela amandla kanye nezindawo zokusebenzelana ezinesivinini esimaphakathi. Nokho, ukuhluka kukaDkt okunemikhawulo yefrikhwensi kanye nezinga lokushisa ngokunemba kwezinhlelo zokusebenza ze-RF. I-Thermal conductivity ihlala inesizotha ku-0.3-0.4 W/m·K, idinga idizayini yendiza yethusi ngokucophelela yokusabalalisa ukushisa okwanele.

I-Polyimide kanye ne-High-Temperature Laminates

Izinto ze-PCB ze-semiconductor ezisekelwe ku-polyimide zimelana nokusebenza okuqhubekayo ku-200°C kanye namazinga okushisa okuguquka kwengilazi angaphezu kuka-250°C. Lokhu kuzinza kokushisa kwenza imijikelezo eminingi yokugeleza ngaphandle kokuhlukanisa noma ukuphambuka kobukhulu. Amanani e-CTE azungeze i-12-16 ppm/°C ahlinzeka ngokufanelana okungcono namaphakheji e-ceramic kune-epoxy resins ejwayelekile.

Lezi zinto zihamba phambili ku-automotive underhood electronics, izinhlelo zokusebenza ze-aerospace, kanye nokupakishwa kwe-flip-chip okuthuthukisiwe lapho ukuhamba ngebhayisikili okushisayo kudlula imijikelezo engu-1000. Ukuhwebelana kuhilela ukumuncwa komswakamo okuphezulu kunezinto ze-PTFE nezinto zokulahla eziphakeme ngokusesilinganisweni ze-0.008-0.012 ku-10 GHz.

I-PTFE kanye ne-PTFE-Composite Materials

I-PTFE emsulwa inikeza ukusebenza kahle kukagesi okumangalisayo ngamanani e-Dk angu-2.1 kanye nezici zokusaphazeka ezingaphansi kuka-0.0002 kuwo wonke amaza e-microwave. Izinhlanganisela ze-PTFE-ceramic zandisa i-Dk ibe ngu-2.2-10.2 yemiklamo ye-impedance elawulwayo ngenkathi igcina i-Df ingaphansi kuka-0.002. Lezi zinto ze-semiconductor PCB zibonisa ukusabalala okuncane kwe-dielectric kufika ku-77 GHz.

Ukuhlelwa kwe-antenna ye-Millimeter-wave, izikhulisamsindo ezinomsindo ophansi, nezindlela ze-RF ezinembayo ezifaniswa nesigaba kufuna ukuzinza kwe-PTFE. Izinselelo zifaka phakathi ukunamathela kwethusi okubuthakathaka okudinga ukwelashwa okukhethekile kwendawo kanye nokunwetshwa okushisayo okuphezulu (CTE 70-100 ppm/°C ye-PTFE emsulwa). Izinhlanganisela ze-PTFE ezigcwele ubumba zehlisa i-CTE ziye ku-24-30 ppm/°C kuyilapho kuthuthukisa amandla okusebenza.

I-Ceramic Substrates

Izisekelo ze-Alumina (Al₂O₃) zinikeza ukuqhutshwa kokushisa okungu-24-28 W/m·K nge-CTE engu-6.5-7 ppm/°C. I-aluminium nitride (AlN) ifinyelela ukuqhutshwa kokushisa okungaphezu kuka-170 W/m·K ngenkathi igcina ukufudumeza kukagesi okungaphezu kuka-10¹⁴ Ω·cm. Lezi zinto ze-semiconductor PCB zivumela ukunamathiswa okuqondile ngaphandle kwezinto zokusetshenziswa kwe-polymer thermal interface.

Ama-amplifiers e-RF anamandla aphezulu, amamojula e-IGBT, namaphakeji e-LED athuthukisa ukusebenza okushisayo kwe-ceramic. I-Alumina ibiza kancane kodwa idinga ama-substrates aminyene ukuze kusakazeke ukushisa okwanele. I-AlN's conductivity ephakeme ivumela imiklamo emincane enokumelana nokushisa okuphansi. Imishini yokuphuka kwe-brittle idinga ukuphathwa ngokucophelela phakathi nokuhlanganisa.

Akhethekile RF Laminates

uchungechunge lwe-laminate olukhethekile olunezinga eliphansi lokulahlekelwa kanye nezinto ezifanayo ze-hydrocarbon-ceramic zilinganisela ukusebenza kanye nokukhiqizwa. Imininingwane ejwayelekile ifaka phakathi i-Dk engu-3.38-3.48 enezimo zokushisa ezingaphansi kuka-50 ppm/°C, kanye ne-Df engaphansi kuka-0.004 ku-10 GHz. Lezi zinto ze-semiconductor PCB zicubungula zisebenzisa imishini ye-PCB ejwayelekile ngenkathi ziletha ukuzinza kwebanga le-RF.

Amanethiwekhi esihlungi, amasekhethi ahambelana nesikhulisi samandla, namaphethelo e-radar angaphambili azuza ekubekezeleleni okuqinile kuka-D (±0.05) nokumunca umswakama ophansi ngaphansi kuka-0.06%. Ngokungafani ne-PTFE ehlanzekile, lawa ma-laminates avumela ukucwenga kwembobo kanye nokwakhiwa kwezingqimba eziningi nge-prepreg evamile. Izikhundla zezindleko phakathi kwezinhlanganisela ze-high-Tg FR-4 kanye ne-PTFE zizenza zilungele ukukhiqizwa kwevolumu ye-RF.

I-Metal-Core kanye ne-Insulated Metal Substrates

Amapuleti esisekelo se-aluminium noma ethusi ahambisa ukushisa ngokuqondile ukusuka endaweni efakwayo kuya kumaheatsink noma ku-chassis. Izendlalelo ze-Dielectric ezisukela kuma-micrometer angama-50 kuye kwangama-200 zihlukanisa imikhondo yesekethe kusuka kumongo wensimbi. Amanani okumelana nokushisa afinyelela ku-0.5-2 °C·cm²/W kuye ngogqinsi lwe-dielectric kanye ne-thermal conductivity.

Amalungu afanayo e-LED yamandla, amadrayivu ezimoto, namasekhethi aphezulu anohlangothi olulodwa asebenzisa izinto ze-PCB ze-metal-core semiconductor zokuphatha okushisayo. Lawa ma-substrates ngokuvamile asekela kuphela amasekhethi anezinhlangothi ezimbili kuphela, akhawulela ubunkimbinkimbi bemizila uma kuqhathaniswa ne-multilayer ceramic noma i-organic substrates.

Uhlaka Lwesinqumo Sokukhetha Okubalulekile

Ukukhetha Okusekelwe Imvamisa

Imvamisa yokusebenza ibeka imingcele yokuqala yezinto ze-semiconductor PCB:

• Ngaphansi kuka-1 GHz - I-High-Tg FR-4 inikeza ukuzinza okwanele kwe-dielectric kumasekhethi amaningi e-analog edijithali nesivinini esimaphakathi anezinzuzo zezindleko.
• 1-10 GHz ububanzi – Izinto eziphansi ze-Df ezine-laminate yohlobo lwe-laminate olusezingeni eliphansi kanye nama-PTFE composites njengezinto eziyinhloko zokuqina kwesignali.
• Ngaphezulu kwe-20 GHz – Izinto ze-PTFE-based semiconductor PCB zinciphisa ukulahlekelwa kokufaka kanye nokuhlanekezelwa kwesigaba ezinhlelweni ze-millimeter-wave.
• Izinhlelo zokusebenza ze-Broadband - Izinto ezinokuhlakazeka okuncane kuka-Dkt kuyo yonke imvamisa kuvimbela ukuhluka kokulibaziseka kweqembu kumasistimu e-wideband.

Ukucabangela Ukuminyana kwamandla

Izidingo zokuguquguquka kokushisa ziqhuba ukukhethwa kwezinto ezishisayo. Ukulahla ngaphansi kuka-5 W/cm² kuvumela ama-substrates emvelo avamile anama-thermal vias nezindiza zethusi. Ukushisa okusuka ku-5-15 W/cm² kudinga imiklamo yensimbi-core noma ukwakhiwa kwethusi eliwugqinsi ngokushisa okuthuthukisiwe kusetshenziswa amalungu afanayo. Izinhlelo zokusebenza ezingaphezu kuka-15 W/cm² zidinga ama-substrates e-ceramic noma izakhiwo ezihlanganisiwe ezihlanganisa iziqhingi zendawo zobumba nezendlalelo ze-organic umzila.

Izimfuneko Zebanga Lokushisa

Amazinga okushisa emvelo azisa ukufaneleka kwezinto ezibonakalayo ze-semiconductor PCB materials. Izilinganiso zezimboni ezijwayelekile (-40 kuya ku-85°C) zifanelana nezinto ze-epoxy ze-Tg ephezulu. Izinhlelo zokusebenza zezimoto zangaphansi kanye ne-aerospace ezidinga -55 kuya ku-150°C ukuqhubeka nokusebenza zigunyaza amasistimu asekelwe ku-polyimide. Izinga lokushisa eliphakeme lokugeleza kabusha elingaphezu kuka-260°C noma imijikelezo yokushisa eningi ithanda i-polyimide noma amasistimu e-epoxy asebenza kahle kakhulu anokumelana okufakazelwe ukubola.

Ukuhambisana Kwenqubo Yokukhiqiza

Amandla enqubo yokuhlanganisa avala iluphu yokukhetha. Imigqa ejwayelekile ye-SMT icubungula i-FR-4 kanye nama-laminate e-laminate akhethekile aphansi okulahlekelwa ngaphandle kokuguqulwa kwemishini. Izinto ze-PTFE zidinga amapharamitha okubhoboza aguquliwe, ukwelashwa kwe-plasma kokunamathela, kanye nemijikelezo yokucindezela elawulwayo. Izisekelo ze-ceramic zidinga imishini ekhethekile yokwenza insimbi kanye nezinqubo zokushisa okuphezulu noma zokufaka insimbi ezingahambisani nezingxenye eziphilayo.

Ukucatshangelwa Kokukhiqiza Kwezinto Ze-Semiconductor PCB

I-Copper Foil ne-Surface Finish

Ukukhethwa kwefoyili yethusi kunomthelela kukho kokubili ukusebenza kukagesi nokushisa ezintweni ze-semiconductor PCB. Ithusi elijwayelekile elenziwe nge-electrodeposited (0.5-2 oz) lanele umzila wesignali, kuyilapho ithusi elisindayo (3-10 oz) linciphisa ukulahlekelwa okuphikisayo ekusabalaliseni amandla. Amafoil ekhopha anephrofayili ephansi kakhulu anciphisa imiphumela yokuhwaya kwendawo ekulahlekeni kokufakwa ngaphezu kuka-10 GHz, okubalulekile ekugcineni izinzuzo ze-Df eziphansi.

I-Surface finish chemistry ithinta ukuthengiselana nokuthembeka kwesikhathi eside. Igolide le-nickel immersion gold (ENIG) linikeza impilo yeshalofu enhle kakhulu nokuhambisana kwe-wire bonding kodwa yethula ukulahlekelwa kwesignali kumafrikhwensi aphezulu. Isiliva lokucwiliswa noma i-organic solderability preservative coatings inciphisa ukulahlekelwa kokufaka kodwa idinga ukugcinwa okucophelela kanye nokuqinisekiswa kokuhambisana kwe-solder okungenayo umthofu.

Izinselele Zokucubungula Izinto

Izinselele zokubopha i-PTFE zidinga i-plasma noma i-sodium etching ukuze kuthuthukiswe ukunamathela ngaphambi kokucwenga. Ukumba kukhiqiza udoti owuchungechunge odinga ijeometri yamathuluzi akhethekile kanye nesivinini sokuphotha esiphakeme kune-FR-4 evamile. Imishini yobumba isebenzisa i-laser ablation noma i-ultrasonic drilling esikhundleni sezinqubo ezivamile zemishini, ikhawulela ngokusebenzisa ukuguquguquka kokubeka.

Ukuhlola Ukuqinisekiswa Kwedizayini

Umklamo wokubuyekezwa kokwenziwa kufanele kwenzeke kusenesikhathi ekukhethweni kwezinto ze-PCB ze-semiconductor. Ukwakhiwa kweprototype kuqinisekisa ukusebenza kokujikeleza kokushisa, ikhono lokubhalisa kusuka kungqimba kuya kungqimba, nangokuthembeka ngokuhlolwa kokushisa-komswakama-ukubandlulula. Ukulinganiswa kwepharamitha ye-S kuqinisekisa ukusebenza kukagesi kufana namamodeli okulingisa ngokusekelwe kudatha yezinto ezibonakalayo, kwembula noma yikuphi ukungafani phakathi kwamanani acacisiwe nawangempela e-Dk noma e-Df.

Izibonelo Isicelo

I-RF Front-End Module Design

Imojula ye-radar ye-X-band front-end idinga izindlela zesignali ezihambisana nesigaba ngokulahlekelwa kokufakwa okungaphansi kuka-0.5 dB ku-8-12 GHz. Ithimba lobunjiniyela likhethe i-laminate ekhethekile ephansi yokulahlekelwa (Dk 3.48, Df 0.004) yezingxenye ze-RF, isebenzisa imigqa ye-microstrip elawulwayo ene-±5 ohm tolerance. Ukuhlaziywa kokushisa kwembule ukusatshalaliswa okungu-8 W kusuka ku-amplifier yamandla, okuqondiswe ngokusebenzisa ama-vias okushisa angu-0.3 mm axhumanisa nendiza yethusi yangaphakathi.

Ukuphathwa Okushisayo Kwemojula Yamandla

Idizayini yemojula yamandla e-silicon carbide egxile ku-aluminium nitride substrate izuze ukumelana nokushisa kwe-junction-to-case okungu-0.15 °C/W ngenkathi ibamba amandla aphakeme angu-15 kW. I-AlN substrate (ubukhulu obungu-0.63 mm, 170 W/m·K conductivity eshisayo) ifake ukujikeleza kwethusi okuboshiwe okuqondile okusekela u-200 A ukuminyana kwamanje. Ukufaniswa kwe-CTE ne-SiC die (4.5 ppm/°C) kuqede ukukhathala kwentambo yebhondi ebonwe kumiklamo yangaphambilini esekelwe ku-alumina.

Isiphetho

Ukukhetha izinto ze-Semiconductor PCB kubeka phambili impendulo yemvamisa nokuphathwa okushisayo kuyilapho kuhlonipha izithiyo zokwenziwa kanye nezindleko ezihlosiwe. Qondanisa izakhiwo ze-dielectric ukuze ubonise izidingo zobuqotho kuqala, bese uqinisekisa ukufaneleka kwedizayini eshisayo ngokulingisa nokuhlolwa kwe-prototype. Ukucaciswa kwezinto ezibonakalayo kufanele kufake idatha ephelele ka-Dk ne-Df kuwo wonke amaza okusebenza, izilinganiso ze-thermal conductivity, ukucaciswa kwezinhlamvu ze-CTE, kanye nemiphumela yokuhlolwa kokufaneleka.

Highleap Electronics Amakhono Obuchwepheshe

• Ubuchwepheshe bezinto ezibonakalayo - Ukusekelwa kobunjiniyela ekukhetheni izinto ze-PCB ze-semiconductor ngokusekelwe kugesi, izimfuneko ezishisayo, nokuthembeka kuyo yonke i-FR-4, i-polyimide, i-PTFE, i-ceramic, ne-specialty RF laminates.
• Ukwenziwa okuthuthukile kwe-PCB – Ukubhola okunembayo nokucutshungulwa kwe-laser kwe-PTFE nama-ceramic substrates anobubanzi bomugqa ofika kuma-micrometer angu-75 nokunemba kokubhalisa ngaphakathi kwama-micrometer angu-25.
• Ukuphathwa kwe-thermal design - Ugqinsi lwethusi lufika ku-10 oz, olushisayo ngama-arrays, nokuhlanganiswa kwensimbi-core kuma-electronics amandla kanye nezinhlelo zokusebenza ze-LED ezikhanya kakhulu.
• Amandla e-RF - Ukulawulwa kokuphazamiseka komzila okubekezelela okungu-±5 ohm, ukucubungula kwezinto ezilahlekelwe kakhulu, kanye nokuqinisekiswa kwepharamitha ye-S yamafrikhwensi afika ku-40 GHz.
• Izinkonzo zomhlangano - Ukugeleza kabusha okungenayo i-lead kanye nezinga eliphezulu lokushisa, i-wire bonding, i-die attach, kanye nokukhipha okungagcwali phansi kwama-substrates okupakisha athuthukile.

Xhumana nethimba lethu lobunjiniyela ukuze nixoxe ngezincomo zezinto zokwakha kanye nokwenza ngcono umklamo wephrojekthi yakho elandelayo ye-semiconductor PCB. Sinikeza isiqondiso sokukhetha izinto zokwakha, ukubuyekezwa komklamo wokuhlanganisa, kanye nokusekelwa kokuthuthukiswa kwamaphrothokholi ukuze kusheshiswe umjikelezo wakho wokuthuthukiswa komkhiqizo.

imibuzo ejwayelekile ukubuzwa

1. Kunini lapho ama-substrates e-ceramic kufanele athathe indawo yezinto zensimbi-core?

I-Ceramic iba isibopho ngaphezu kuka-15-20 W/cm² ukushisa okuguquguqukayo noma lapho ukufanisa i-CTE nokufa okungenalutho kubalulekile kuma-flip-chip assembles. Izinto ze-Metal-core semiconductor PCB azikwazi ukuzuza ukuqhutshwa kokushisa okudlula u-5 W/m·K ngongqimba lwe-dielectric. Ukwengeza, i-ceramic imelana nezinga lokushisa elingaphezu kuka-200 ° C lapho ama-organic dielectrics ehla.

2. Ngabe ukulahlekelwa kuthinta kanjani ukusebenza kwesistimu?

Ukwenyuka ngakunye okungu-0.001 ku-Df kunikela cishe ukulahlekelwa kokufaka okungu-0.05 dB/intshi ku-10 GHz kwemigqa engu-50-ohm microstrip. Ngomzila we-RF ongu-4-intshi, ukukhetha izinto ze-semiconductor PCB ene-Df engu-0.004 iqhathaniswa no-0.001 kwengeza ukulahlekelwa okungu-1.2 dB, kunciphisa ngokuqondile ukuzwela komamukeli. Amasistimu azwela isigaba afana namalungu afanayo ahlukaniswe ngezigaba athola amaphutha okukhomba umugqa ngokulingana nokuhluka kwe-tangent yokulahlekelwa phakathi kwamashaneli.

3. Ingabe izinto zokwakha zingafinyelela kokubili i-Tg ephezulu ne-Df ephansi?

I-epoxy chemistry ejwayelekile idala ukuhwebelana phakathi kokuzinza kokushisa nokusebenza kukagesi, njengoba izithibi zomlilo ezine-brominated zandisa i-Df. Izinto ze-PCB ze-semiconductor ezithuthukisiwe njenge-polyimide kanye ne-PTFE-ceramic composites zinqoba lo mkhawulo, ziletha i-Tg ngaphezu kuka-250°C nge-Df ngaphansi kuka-0.003. Ama-laminate e-CLTE-XT akhethekile ane-low loss abonisa lokhu kulinganisela ngezinhlelo ze-hydrocarbon resin.

4. Yikuphi ukubekezelelana kukaDkt okudingekayo ku-impedance elawulwayo?

Ukunemba kokuphazamiseka phakathi kuka-±10% kudinga ukubekezelelwa kuka-Dkt kuka-±0.2 kumajiyometri we-strip ajwayelekile kanye ne-microstrip. Izinhlelo zokusebenza zemvamisa ephezulu ngezansi ±5 ohm ukubekezelelana zidinga okokusebenza kwe-semiconductor PCB ecacisa ukubekezelela kuka-Dk ±0.05 noma okuqinile. Imininingwane yedatha yezinto ezibonakalayo kufanele ifake phakathi ukuhluka kuka-Dkt ngamafrikhwensi, izinga lokushisa, kanye nephaneli yonkana ukuze kunikwe amandla ukumodela okunembile kwe-impedance.

5. Kufanele ngibahlaziye kanjani abahlinzeki bezinto ezibonakalayo abangabajwayele?

Cela idatha yokuhlola yenkampani yangaphandle kumalebhu azimele abonisa u-Dk kanye ne-Df elinganiswa ngezindlela ze-split-post dielectric resonator ngayinye ye-IPC-TM-650. Qinisekisa i-CTE ngokuhlaziywa kwe-thermomechanical futhi uqinisekise i-Tg ngokusebenzisa i-calorierimetry yokuskena okuhlukile. Dala amakhuphoni okuhlola afaka i-fine-pitch vias, ama-impedance traces alawulwayo, nezimoto zokuhlola ukuhamba ngamabhayisikili ashisayo ngaphambi kokuzibophezela kokukhiqiza.