Difference between revisions of "Chemical Etchants"

From OpenCircuits
Jump to navigation Jump to search
m (Protected "Chemical Etchants": spam magnet [edit=sysop:move=sysop] (expires 02:48, 16 October 2007 (UTC)))
Line 1: Line 1:
−
{{stub}}
+
[http://pumamiharayasuhiro.beawy.cn/ puma miharayasuhiro 40] [http://sonymdr-ds3000.cubik.cn/ sony mdr-ds3000] [http://braunflexxpii5715.tropa.cn/ braun flex xp ii 5715] [http://leers.cn/index1_250.html site] [http://onstagejbl.surer.cn/ on stage jbl] [http://nadasintieros.tropa.cn/ nada sin ti eros] [http://spidergiococarta.prisce.cn/ spider gioco carta] [http://tubidiprolunga.huerly.cn/ tubi di prolunga] [http://audiocar.routs.cn/ audio car] [http://freecumshot.huerly.cn/ Free cum shot] [http://accessorisamsung.ruffs.cn/ accessori samsung cavo usb] [http://prisce.cn/index2_666.html link] [http://wwwpoliziadi.bearr.cn/ w w w polizia di stato it] [http://nauticausatotrentino.beawy.cn/ Nautica usato trentino] [http://tamautomazione.ruffs.cn/ tam automazione srl] [http://thegentlemanbandit.exacli.cn/ the gentleman bandit] [http://palmaretyphoon.cubik.cn/ palmare typhoon] [http://lampadaemergenza.vilver.cn/ lampada emergenza] [http://nontipassapiu.beawy.cn/ non ti passa piu mp3] [http://julianasilveira.routs.cn/ juliana silveira] [http://thrustmaster.exacli.cn/ thrustmaster beretta 92fs] [http://vessillorosso.vilver.cn/ vessillo rosso] [http://insegneluminose.tropa.cn/ insegne luminose modena] [http://tizianotelecom.vilver.cn/ tiziano telecom fax] [http://fumarecarrlibri.cubik.cn/ fumare carr libri] [http://perunpugnodidollari.prisce.cn/ per un pugno di dollari mp3] [http://neo2k8n.vilver.cn/ neo2 k8n] [http://eurovision2004.tropa.cn/ eurovision 2004 song] [http://corinapoletani.beawy.cn/ cori napoletani] [http://hpipaqhw6510mobile.surer.cn/ hp ipaq hw6510 mobile messenger] [http://leftousidealone.leers.cn/ left ouside alone] [http://lavatricirex.huerly.cn/ lavatrici rex avant] [http://keyssky.ruffs.cn/ keys sky] [http://remizero.cubik.cn/ remi zero] [http://dovrefjell.huerly.cn/ dovrefjell] [http://pentium4775.exacli.cn/ pentium4 775] [http://usb5gb.tropa.cn/ usb 5 gb] [http://boubleboll.leers.cn/ bouble boll] [http://glares.cn/ glares.cn] [http://hongnhunggallery.beawy.cn/ hong nhung gallery] [http://cunadovolveras.exacli.cn/ cunado volveras] [http://flyngdoughman.bearr.cn/ flyng doughman] [http://assestiroaspirante.tropa.cn/ asse stiro aspirante] [http://cabron.beawy.cn/ cabron] [http://cuccarini.bearr.cn/ cuccarini] [http://lg-l1715s.exacli.cn/ lg - l1715s] [http://cubik.cn/index0_1000.html homepage] [http://panasonicsc-pm91.prisce.cn/ panasonic sc-pm91] [http://californiadi.leers.cn/ california di the o c] [http://sanantoniocile.ruffs.cn/ san antonio cile] [http://scannerperradiografie.vilver.cn/ scanner per radiografie] [http://flamenko.cubik.cn/ flamenko] [http://rexfi260sa.bearr.cn/ rex fi 260 sa] [http://ringii-ilcrepuscolo.glares.cn/ ring ii - il crepuscolo degli dei] [http://figamatura.brouj.cn/ figa matura] [http://xd-picturecard.tropa.cn/ xd-picture card] [http://lillo.beawy.cn/ lillo] [http://camereamodena.surer.cn/ camere a modena] [http://tonerq2612a.cubik.cn/ toner q2612a] [http://portatileecs.bearr.cn/ portatile ecs] [http://toshibamk8026gax.routs.cn/ toshiba mk8026gax] [http://prisce.cn/ prisce.cn] [http://diyet.leers.cn/ diyet] [http://mmcnokia6680.routs.cn/ mmc nokia 6680] [http://mailfinmatica.leers.cn/ mail finmatica net] [http://losannacosefare.vilver.cn/ losanna cose fare] [http://chatamico.surer.cn/ chat amico] [http://leers.cn/ leers.cn] [http://zuban.tropa.cn/ zuban] [http://laurapausini.vilver.cn/ laura pausini resta in ascolto] [http://codicirsi.prisce.cn/ codici rsi] [http://esperanza.brouj.cn/ esperanza] [http://pianetalottoit.surer.cn/ pianetalotto it] [http://notthatkindanastacia.leers.cn/ not that kind anastacia] [http://mialmacanta.cubik.cn/ mi alma canta] [http://usbsdcardreader.prisce.cn/ usb sd card reader] [http://cdpausini.bearr.cn/ cd pausini] [http://casedicampagna.bearr.cn/ case di campagna] [http://terrateccinergy.ruffs.cn/ terratec cinergy dvb-t] [http://portatiliintel.vilver.cn/ portatili intel centrino da 15] [http://tundertigher.bearr.cn/ tunder tigher] [http://redhotchili.glares.cn/ red hot chili peppers live] [http://estrattoconto.brouj.cn/ estratto conto contributi inps] [http://mp3linein.bearr.cn/ mp3 line in] [http://tunisair.ruffs.cn/ tunisair] [http://responsabileufficio.leers.cn/ responsabile ufficio tecnico regione emilia romagna - rimini provincia] [http://vilver.cn/index0_666.html site] [http://unacoltinpugno.ruffs.cn/ una colt in pugno al diavolo] [http://ufficiodelregistro.brouj.cn/ ufficio del registro] [http://dressed.huerly.cn/ dressed] [http://lcdphilips170.ruffs.cn/ lcd philips 170] [http://brouj.cn/index5_666.html page] [http://computacion.prisce.cn/ computacion] [http://bushnellpowerview.exacli.cn/ bushnell powerview 16x32] [http://ilmurojuventus.exacli.cn/ il muro juventus] [http://berserkdisc01.beawy.cn/ berserk disc 01] [http://titta.exacli.cn/ titta] [http://toschibasatellite.leers.cn/ toschiba satellite pro] [http://tropa.cn/ tropa.cn] [http://kdellosreyes.exacli.cn/ k del los reyes] [http://www.psyhautopsy.as.ro/web/universita-modena/ universita modena] [http://xobitips.5gbfree.com/new/sposalizio/ sposalizio] [http://jcarino.netfirms.com/usb-18.htm usb 250 gb] [http://slaider2005.idilis.ro/content/fungo-gorizia/ fungo gorizia] [http://feelosof.netfirms.com/fotoerotiche/ fotoerotiche] [http://videlais.netfirms.com/new/video-decapitazione14.htm video decapitazione berg] [http://xobitips.5gbfree.com/new/cristian-castro/ cristian castro] [http://www.psyhautopsy.as.ro/web/testo-canzone146/ testo canzone superstar] [http://vla5.netfirms.com/web/educacion-fisica.htm educacion fisica] [http://reptilian-lace.netfirms.com/content/fotocamere-olympus/ fotocamere olympus] [http://jelively.at.tut.by/new/elezioni-lecce.htm elezioni lecce 2004] [http://xobitips.5gbfree.com/new/d-canon/ d30 canon] [http://vla5.netfirms.com/web/calciofemminile-veneto.htm calciofemminile veneto] [http://cry-tomorrow.netfirms.com/topic/incintri-supereva.html incintri supereva it] [http://cry-tomorrow.netfirms.com/topic/learning-to.html learning to fly] [http://jcarino.netfirms.com/anna-e1.htm anna e i lupi] [http://jziloh.12gbfree.com/reale-mutua/ reale mutua assicurazione] [http://jziloh.12gbfree.com/diamants/ diamants] [http://xobitips.5gbfree.com/new/gigaset-siemens/ gigaset siemens cordless] [http://www.ahrorchik55.as.ro/description/amstrad-cd.htm amstrad cd] [http://xobitips.5gbfree.com/new/nancy-dell/ nancy dell olio] [http://listmonstrik20.idilis.ro/ixus2.htm ixus400] [http://lonely-doll.idilis.ro/web/panasonic-aspirapolvere/ panasonic aspirapolvere] [http://iamskinhead.idilis.ro/resources/turtles-ninjas.html turtles ninjas] [http://lonely-doll.idilis.ro/web/legnano-ciclismo/ legnano ciclismo] [http://reptilian-lace.netfirms.com/content/buble-bum/ buble bum] [http://jziloh.12gbfree.com/custodia-treo/ custodia treo] [http://xobitips.5gbfree.com/new/sdram-/ sdram 256 pc100 144pin] [http://feelosof.netfirms.com/you-ve/ you ve got friend] [http://jziloh.12gbfree.com/capitalone/ capitalone] [http://reptilian-lace.netfirms.com/content/laetitia-casta3/ laetitia casta] [http://reptilian-lace.netfirms.com/content/brain-injury1/ brain injury lawyer] [http://xobitips.5gbfree.com/new/braun-softperfection/ braun softperfection body e face] [http://reptilian-lace.netfirms.com/content/hauppauge-nova3/ hauppauge nova] [http://iamskinhead.idilis.ro/resources/micro-atx.html micro atx 754] [http://jelively.at.tut.by/new/code-tps13.htm code tps 09 2004] [http://jziloh.12gbfree.com/appunti-diritto/ appunti diritto tributario] [http://www.karvero206.as.ro/description/fossil-salerno.htm fossil salerno] [http://reptilian-lace.netfirms.com/content/v-bifuel/ v70 bifuel] [http://lynnemicur.idilis.ro/blog/toner-infoprint/ toner infoprint 1120] [http://viaggiatore87.idilis.ro/description/dieci-cento1/ dieci cento mille lyrics] [http://jziloh.12gbfree.com/ww-carabinieri/ ww carabinieri it] [http://jziloh.12gbfree.com/vigliaccheria/ vigliaccheria] [http://xobitips.5gbfree.com/new/laserjet-aio/ laserjet 2840aio] [http://thjulia.at.tut.by/resources/filati-a.htm filati a stock] [http://jziloh.12gbfree.com/stampante-stylus/ stampante stylus photo r1800] [http://listkolobok11.idilis.ro/costumi-winx.html costumi winx per carnevale] [http://jziloh.12gbfree.com/fobia/ fobia] [http://www.karvero206.as.ro/description/ati-radeon54.htm ati radeon x800 xt pcie] [http://willowing.idilis.ro/new/guadagna-con1.html guadagna con sondaggio] [http://jziloh.12gbfree.com/www-dps/ www dps state la us lsp] [http://jziloh.12gbfree.com/prova-di/ prova di matematica pni] [http://jziloh.12gbfree.com/di-sole/ di sole ed azzurro] [http://vla5.netfirms.com/web/la-planta1.htm la planta del albania] [http://willowing.idilis.ro/new/volanis-sotis.html volanis sotis] [http://xobitips.5gbfree.com/new/indocina-film/ indocina film] [http://xobitips.5gbfree.com/new/omicidio-a/ omicidio a pagamento] [http://viaggiatore87.idilis.ro/description/cerco-uomo/ cerco uomo] [http://vla5.netfirms.com/web/cherubini-musical.htm cherubini musical roma] [http://jziloh.12gbfree.com/birdhunter/ birdhunter] [http://www.ahrorchik55.as.ro/description/techno-house.htm techno house] [http://jziloh.12gbfree.com/lebt-denn/ lebt denn der alte holz michel noch] [http://listmonstrik20.idilis.ro/thupac.htm thupac] [http://xobitips.5gbfree.com/new/marillion-marbles/ marillion marbles on the road] [http://xobitips.5gbfree.com/new/occhiali-oakley/ occhiali oakley half jacket] [http://videlais.netfirms.com/new/liquori.htm liquori] [http://jcarino.netfirms.com/tour-settembre.htm tour settembre 2004 giorgia] [http://www.psyhautopsy.as.ro/web/malabo/ malabo] [http://jziloh.12gbfree.com/fuck-u/ fuck u too] [http://jziloh.12gbfree.com/marmi-e/ marmi e pietre] [http://jziloh.12gbfree.com/film-vi/ film vi presento joe black con brad pitt] [http://lynnemicur.idilis.ro/blog/sovrintendenza-per/ sovrintendenza per i beni archeologici] [http://feelosof.netfirms.com/odessa-in/ odessa in fiamme] [http://videlais.netfirms.com/new/jane-seggiolini.htm jane seggiolini auto] [http://thjulia.at.tut.by/resources/logitech-webcam10.htm logitech webcam quickcam messenger] [http://www.ahrorchik55.as.ro/description/cinema-a2.htm cinema a venezia (mestre)] [http://lynnemicur.idilis.ro/blog/salvini/ salvini] [http://www.ahrorchik55.as.ro/description/il-progetto.htm il progetto della bellezza il design fra] [http://iamskinhead.idilis.ro/resources/zofilia.html zofilia] [http://vla5.netfirms.com/web/billy-bud.htm billy bud] [http://thjulia.at.tut.by/resources/acer-62.htm acer 17 tft al1711] [http://xobitips.5gbfree.com/new/sap-chimica/ sap (chimica)] [http://jziloh.12gbfree.com/gabry-ponte/ gabry ponte streghe] [http://reptilian-lace.netfirms.com/content/air-plus/ air plus nike calzature] [http://xobitips.5gbfree.com/new/trans-abruzzo/ trans abruzzo] [http://jziloh.12gbfree.com/www-promessi/ www promessi sposi it] [http://xobitips.5gbfree.com/new/foto-baby/ foto baby h] [http://vla5.netfirms.com/web/www-libero7.htm www libero porno it] [http://xobitips.5gbfree.com/new/identidad/ identidad] [http://videlais.netfirms.com/new/escuchar-la1.htm escuchar la cancion de axel amo] [http://jcarino.netfirms.com/cartoline-della.htm cartoline della vergine] [http://jziloh.12gbfree.com/frigocongelatore-da/ frigocongelatore da incasso ariston] [http://jziloh.12gbfree.com/newport-news/ newport news va] [http://xobitips.5gbfree.com/new/decoder-chiaro/ decoder chiaro] [http://feelosof.netfirms.com/dieci-immagini1/ dieci immagini per industry giant 2] [http://jziloh.12gbfree.com/gdje-je/ gdje je sad] [http://jziloh.12gbfree.com/monitor-samsung/ monitor samsung] [http://feelosof.netfirms.com/www-mature1/ www mature it] [http://reptilian-lace.netfirms.com/content/rocky-mountains/ rocky mountains] [http://iamskinhead.idilis.ro/resources/messina-coppie.html messina coppie] {{stub}}
  
 
After masking off the parts of the copper-clad board you want to keep, you need to remove the parts you don't want to keep. This is usually done by chemically etching away the copper. There are a lot of different chemical techniques for doing this, each with its own advantages and drawbacks.
 
After masking off the parts of the copper-clad board you want to keep, you need to remove the parts you don't want to keep. This is usually done by chemically etching away the copper. There are a lot of different chemical techniques for doing this, each with its own advantages and drawbacks.
Line 8: Line 8:
 
This is the most common hobbyist etchant. Ferric chloride, FeCl<sub>3</sub>, is a brownish substance. It's usually sold in a bottle (dissolved in water, perhaps with a little acid or peroxide) or as a powder (which you have to dissolve in water).
 
This is the most common hobbyist etchant. Ferric chloride, FeCl<sub>3</sub>, is a brownish substance. It's usually sold in a bottle (dissolved in water, perhaps with a little acid or peroxide) or as a powder (which you have to dissolve in water).
  
−
When in solution, ferric chloride is a ferric ion (Fe<sup>3+</sup>) and a chloride ion (Cl<sup>-</sup>). The ferric ion reacts with the metallic copper on the circuit board in a redox reaction, producing a ferrous ion (Fe<sup>2+</sup>) and cuprous or cupric (Cu<sup>1+</sup> or Cu<sup>2+</sup>) copper. The chlorine is just along for the ride. The copper ion, unlike the metallic copper, is soluble, so it leaves the circuit board and goes into solution. The reaction products form a black sludge which settles to the bottom of the etching tank. After etching enough copper, all your Fe<sup>3+</sup> is used up and your solution is full of Cu<sup>1+</sup>, and you need to get more etchant.
+
When in solution, ferric chloride is a ferric ion (Fe<sup>3 </sup>) and a chloride ion (Cl<sup>-</sup>). The ferric ion reacts with the metallic copper on the circuit board in a redox reaction, producing a ferrous ion (Fe<sup>2 </sup>) and cuprous or cupric (Cu<sup>1 </sup> or Cu<sup>2 </sup>) copper. The chlorine is just along for the ride. The copper ion, unlike the metallic copper, is soluble, so it leaves the circuit board and goes into solution. The reaction products form a black sludge which settles to the bottom of the etching tank. After etching enough copper, all your Fe<sup>3 </sup> is used up and your solution is full of Cu<sup>1 </sup>, and you need to get more etchant.
  
 
== Ammonium Persulfate ==
 
== Ammonium Persulfate ==
−
Expensive & hard to control and optimize the process parameters (such as specific gravity & pH value).
+
Expensive
−
 
 
−
== HydroChloric Acid / Hydrogen Peroxide ==
 
−
 
 
−
Mixing about 1 part HCl (Which can be found at most hardware stores, also known as Muriatic Acid. Ask for concrete cleaner.) into 2 parts Hydrogen peroxide (normally used for cleaning cuts) you can make a fairly powerful etchant. Use gloves and don't breathe the fumes though. This will etch a 3"x5" board in less than 10 minutes. No need to heat it up. I usually like to drill a small hole through the board on a corner and thread a wire or nylon string through to help agitate / remove the board.
 
−
 
 
−
When the board is done etching, the etchant will probably look like green kool-aid, from the copper content in it. This stuff is highly corrosive and will burn skin, which is why you should wear gloves. But it is easy to handle, and fairly easy to dispose of. the etchant is easily deactivated with baking soda. Pour enough baking soda into it slowly (to keep it from boiling and overflowing... remember what happens with baking soda/vinegar? ya...) until it is a solid mass, then leave it in the sun to dry. You should contact your local authorities to find out what you should do with it next. Whatever you do, DO NOT dump the stuff down the drain, it will eat through your pipes just like any of the other etchants.
 
−
 
 
−
== Sodium Persulfate ==
 
−
More environmentally friendly than ferric chloride.  Can monitor the etching as initially clear new etchant solution turns blue from the copper ions.
 
−
 
 
−
== Acid Cupric Chloride ==
 
−
Dead simple etchant made from ordinary, store-bought chemicals (hydrochloric acid and hydrogen peroxide). Has the advantage that it can be regenerated by bubbling oxygen/air through it, or by adding more H<sub>2</sub>O<sub>2</sub>. In addition, it doesn't get used up: the etchant bath simply grows with use (kind of like sourdough starter…)
 
−
The used etchant also makes a great algecide/pH reducer for your pool (and a whole lot cheaper than that stuff they sell at the pool store).
 
−
 
 
−
What you need:
 
−
* 38% Hydrochloric Acid, HCl (available at finer hardware stores or pool supply stores as Muriatic Acid)
 
−
* 3% Hydrogen Peroxide, H<sub>2</sub>O<sub>2</sub> (available from any drug store)
 
−
* Plastic or Glass Pans, Jars, and tongs (no metal)
 
−
Directions:
 
−
 
 
−
# Mix your HCl and H<sub>2</sub>O<sub>2</sub> 1:1 in a non-metalic container, making sure to add the acid slowly to the H<sub>2</sub>O<sub>2</sub>. DO NOT ADD THE H<sub>2</sub>O<sub>2</sub> TO THE ACID!!!
 
−
# After you've masked your board, dip it in the solution and constantly agitate. You should notice a dark green cloud start to come from the board almost immedately which quickly dissapears or turns lighter as it gets further from the surface of the board.
 
−
# Etching should take about 10min depending on the temperature and how well you agitated the etchant. When all of the copper is gone, dip in water to wash off any stray etchant and stop the reaction.
 
−
# When done etching, save used etchant in a non-metalic container and mark clearly its contents.
 
−
# If your etchant has become a dark, murky green color, add a little bit of H<sub>2</sub>O<sub>2</sub> or bubble air/O<sub>2</sub> through the solution to regenerate it back to a light, transparent green color.
 
−
See links at bottom for more information on the chemistry and some pictures of the process.
 
−
 
 
−
== Disposal procedures ==
 
−
Flushing used etchant down the drain is a bad idea (and usually illegal) because copper ion is toxic. The usual recommended way to dispose of hobbyist amounts of etchant is to convert it to a solid somehow and dispose of the solid in the trash.
 
−
* [http://www.kepro.com/fmc4.htm Kepro Circuit Systems] Removal of Copper and Persulfate from Spent Sodium Persulfate Etchant by Precipitation
 
−
 
 
−
== External Links ==
 
−
* [http://www.k9spud.com/wiki/PCB:Etchants Ferric Chloride vs. Ammonium Persulfate] and other etching chemicals.
 
−
* [http://members.optusnet.com.au/~eseychell/PCB/etching_CuCl/index.html Etching with Air Regenerated Acid Cupric Chloride] — an excellent in-depth page on acid cupric chloride etching by Adam Seychell.
 
−
* [http://esmonde-white.com/etching_pcb.html Etching a Copper PCB with HCl and H2O2]
 
−
 
 
−
[[Category:Techniques]]
 

Revision as of 04:43, 20 October 2007

puma miharayasuhiro 40 sony mdr-ds3000 braun flex xp ii 5715 site on stage jbl nada sin ti eros spider gioco carta tubi di prolunga audio car Free cum shot accessori samsung cavo usb link w w w polizia di stato it Nautica usato trentino tam automazione srl the gentleman bandit palmare typhoon lampada emergenza non ti passa piu mp3 juliana silveira thrustmaster beretta 92fs vessillo rosso insegne luminose modena tiziano telecom fax fumare carr libri per un pugno di dollari mp3 neo2 k8n eurovision 2004 song cori napoletani hp ipaq hw6510 mobile messenger left ouside alone lavatrici rex avant keys sky remi zero dovrefjell pentium4 775 usb 5 gb bouble boll glares.cn hong nhung gallery cunado volveras flyng doughman asse stiro aspirante cabron cuccarini lg - l1715s homepage panasonic sc-pm91 california di the o c san antonio cile scanner per radiografie flamenko rex fi 260 sa ring ii - il crepuscolo degli dei figa matura xd-picture card lillo camere a modena toner q2612a portatile ecs toshiba mk8026gax prisce.cn diyet mmc nokia 6680 mail finmatica net losanna cose fare chat amico leers.cn zuban laura pausini resta in ascolto codici rsi esperanza pianetalotto it not that kind anastacia mi alma canta usb sd card reader cd pausini case di campagna terratec cinergy dvb-t portatili intel centrino da 15 tunder tigher red hot chili peppers live estratto conto contributi inps mp3 line in tunisair responsabile ufficio tecnico regione emilia romagna - rimini provincia site una colt in pugno al diavolo ufficio del registro dressed lcd philips 170 page computacion bushnell powerview 16x32 il muro juventus berserk disc 01 titta toschiba satellite pro tropa.cn k del los reyes universita modena sposalizio usb 250 gb fungo gorizia fotoerotiche video decapitazione berg cristian castro testo canzone superstar educacion fisica fotocamere olympus elezioni lecce 2004 d30 canon calciofemminile veneto incintri supereva it learning to fly anna e i lupi reale mutua assicurazione diamants gigaset siemens cordless amstrad cd nancy dell olio ixus400 panasonic aspirapolvere turtles ninjas legnano ciclismo buble bum custodia treo sdram 256 pc100 144pin you ve got friend capitalone laetitia casta brain injury lawyer braun softperfection body e face hauppauge nova micro atx 754 code tps 09 2004 appunti diritto tributario fossil salerno v70 bifuel toner infoprint 1120 dieci cento mille lyrics ww carabinieri it vigliaccheria laserjet 2840aio filati a stock stampante stylus photo r1800 costumi winx per carnevale fobia ati radeon x800 xt pcie guadagna con sondaggio www dps state la us lsp prova di matematica pni di sole ed azzurro la planta del albania volanis sotis indocina film omicidio a pagamento cerco uomo cherubini musical roma birdhunter techno house lebt denn der alte holz michel noch thupac marillion marbles on the road occhiali oakley half jacket liquori tour settembre 2004 giorgia malabo fuck u too marmi e pietre film vi presento joe black con brad pitt sovrintendenza per i beni archeologici odessa in fiamme jane seggiolini auto logitech webcam quickcam messenger cinema a venezia (mestre) salvini il progetto della bellezza il design fra zofilia billy bud acer 17 tft al1711 sap (chimica) gabry ponte streghe air plus nike calzature trans abruzzo www promessi sposi it foto baby h www libero porno it identidad escuchar la cancion de axel amo cartoline della vergine frigocongelatore da incasso ariston newport news va decoder chiaro dieci immagini per industry giant 2 gdje je sad monitor samsung www mature it rocky mountains messina coppie

Dang symbol.pngThis article is a stub. You can help Open Circuits by expanding it.

After masking off the parts of the copper-clad board you want to keep, you need to remove the parts you don't want to keep. This is usually done by chemically etching away the copper. There are a lot of different chemical techniques for doing this, each with its own advantages and drawbacks.

None of these chemicals is incredibly dangerous, but they can all be toxic or caustic, and should be treated with care. Eye protection and gloves are a very good idea. Before you start, make sure you know how dangerous each chemical is, and figure out what you will need to do if you spill it or get it on yourself. Washing with plenty of water is usually a good start. For some chemicals you may want to keep a neutralizing agent handy. An MSDS (Materials Safety Data Sheet) for the chemical will give you some basic information.

Ferric Chloride

This is the most common hobbyist etchant. Ferric chloride, FeCl3, is a brownish substance. It's usually sold in a bottle (dissolved in water, perhaps with a little acid or peroxide) or as a powder (which you have to dissolve in water).

When in solution, ferric chloride is a ferric ion (Fe3 ) and a chloride ion (Cl-). The ferric ion reacts with the metallic copper on the circuit board in a redox reaction, producing a ferrous ion (Fe2 ) and cuprous or cupric (Cu1 or Cu2 ) copper. The chlorine is just along for the ride. The copper ion, unlike the metallic copper, is soluble, so it leaves the circuit board and goes into solution. The reaction products form a black sludge which settles to the bottom of the etching tank. After etching enough copper, all your Fe3 is used up and your solution is full of Cu1 , and you need to get more etchant.

Ammonium Persulfate

Expensive

Retrieved from "http://www.opencircuits.com/index.php?title=Chemical_Etchants&oldid=9889"