Difference between revisions of "PCB Etching"

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m (Procedure)
(Procedure (the chemical way))
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* HCl + H2O2 / Acide chlorydrique + Peroxyde d'Hydrogène (eau oxygénée) => [http://hackaday.com/2012/04/30/etching-your-own-boards-really-really-fast/ HCl+H2O2 method on Hackaday]
 
* HCl + H2O2 / Acide chlorydrique + Peroxyde d'Hydrogène (eau oxygénée) => [http://hackaday.com/2012/04/30/etching-your-own-boards-really-really-fast/ HCl+H2O2 method on Hackaday]
  
==Procedure (the chemical way)==
+
==Photoresist PCB Etching==
There are 3 main steps
+
*Printing
+
*Transfer
+
*Exposure/Etching
+
  
===Printing===
+
===Parts===
* Print your layout (reversed!) on a glossy support (i.e. magazine paper) with a laser printer/photocopier. Inkjet printers don't work.
+
*Uv light
 +
*Pre-coated photoresist positive pcb
 +
*Lye (NaOH)
 +
*Ammonium persulfate
  
* Cut the paper to the size of the PCB
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===PCB Layout===
 +
The pcb layout should be the positive (black parts are where copper will stay) and *mirrored* image, full size (1:1) of the layout.
  
 +
This layout is printed on standard paper with a laser printer (or copier) and set the toner density to the maximum value. This will make the black part really dark so the light can not pass trough.
  
===Transfer===
+
The paper is then drenched in a 'drying' oil (like sunflower seed oil). This will make the white parts of the paper transparent.  Remove the extra oil carefully.
* First of all, use a fine steel wool to clean your PCB material before transfer. Do not touch the surface with your fingers, as they are acid (somewhere between 4.5 and 6 pH)
+
  
* Put the printed layout on the copper board
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===Exposition===
  
* Set your iron to the max. temperature and apply a lot of pressure without moving (for 2-3 minutes ?)
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Remove the plastic protection on the PCB. Place the printed side of the layout against the copper side of the PCB. Remove the air bubbles captured under the greased paper
  
* Motion the iron around for 5 minutes on the board
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Place the PCB & Layout inside the exposure box. Then let the UV light do the work for 3-4 minutes ''This is a '''completely arbitrary''' timing, we should test different values''
  
(to be continued)
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Remove the PCB & Layout from the exposure box
  
===Etching===
+
===Development===
(to be continued)
+
  
 +
(to be completed)
  
Most of this procedure is highly inspired by the [[http://hubcitylabs.org/diy-pcb-etching-at-hubcitylabs/ Hubcitylab Hackerspace Post CC - BY - 3.0]]
+
===Etching===
 +
 
 +
(to be completed)
  
 
== Safety ==
 
== Safety ==

Revision as of 21:09, 7 December 2012

Description

A logical extension to the Kicad workshop (electronics design) is to realize the designed PCB. There are 3 ways to produce PCBs at FIXME (with the required components):

  • PCB Milling with a CNC Router
  • PCB Etching using toner transfer method
  • PCB Etching using the photosensitive positive method

Goal

  • Make custom PCBs for FIXME members and projects.

Obstacles

PCB Milling with a CNC Router:

  • Cost
  • Make a lot of dust

PCB Etching using toner transfer method:

  • Use chemicals requiring precautions for use

PCB Etching using the photosensitive positive method:

  • Use chemicals requiring precautions for use
  • Need an insolation box
  • Number of step for the process


Components

  • Iron(III) chloride / Perchlorure de fer Corrosive!

or

Photoresist PCB Etching

Parts

  • Uv light
  • Pre-coated photoresist positive pcb
  • Lye (NaOH)
  • Ammonium persulfate

PCB Layout

The pcb layout should be the positive (black parts are where copper will stay) and *mirrored* image, full size (1:1) of the layout.

This layout is printed on standard paper with a laser printer (or copier) and set the toner density to the maximum value. This will make the black part really dark so the light can not pass trough.

The paper is then drenched in a 'drying' oil (like sunflower seed oil). This will make the white parts of the paper transparent. Remove the extra oil carefully.

Exposition

Remove the plastic protection on the PCB. Place the printed side of the layout against the copper side of the PCB. Remove the air bubbles captured under the greased paper

Place the PCB & Layout inside the exposure box. Then let the UV light do the work for 3-4 minutes This is a completely arbitrary timing, we should test different values

Remove the PCB & Layout from the exposure box

Development

(to be completed)

Etching

(to be completed)

Safety

Equipment:

  • Gloves
  • Goggles
  • Lab coat

Docs:

Schedule

Participant