Jump to content

Specific Process Knowledge/Etch/Etching of Chromium: Difference between revisions

BGE (talk | contribs)
Jmli (talk | contribs)
 
(30 intermediate revisions by 5 users not shown)
Line 1: Line 1:
=<span style="background:#FF2800">THIS PAGE IS UNDER CONSTRUCTION</span>[[image:Under_construction.png|200px]]=
'''Unless anything else is stated, everything on this page, text and pictures are made by DTU Nanolab.'''


'''All links to Kemibrug (SDS) and Labmanager Including APV and QC requires login.'''
'''Feedback to this page''': '''[mailto:labadviser@nanolab.dtu.dk?Subject=Feed%20back%20from%20page%20http://labadviser.nanolab.dtu.dk/index.php/Specific_Process_Knowledge/Etch/Etching_of_Chromium click here]'''
<!--Page reviewed by jmli 1/8-2016  -->
<!--Page reviewed by jmli 9/8-2022  -->


'''Feedback to this page''': '''[mailto:labadviser@danchip.dtu.dk?Subject=Feed%20back%20from%20page%20http://labadviser.danchip.dtu.dk/index.php/Specific_Process_Knowledge/Etch/Etching_of_Aluminium click here]'''


==Etching of Chromium==
==Etching of Chromium==
Line 8: Line 12:
Etching of chromium can be done either by wet etch, dry etch or by sputtering with ions.
Etching of chromium can be done either by wet etch, dry etch or by sputtering with ions.
*[[Specific Process Knowledge/Etch/Wet Chromium Etch|Etching of Cr by wet etch]]
*[[Specific Process Knowledge/Etch/Wet Chromium Etch|Etching of Cr by wet etch]]
*[[Specific_Process_Knowledge/Etch/ICP_Metal_Etcher/Aluminium|Etching of Al by dry etch]]
*[[Specific Process Knowledge/Etch/ICP Metal Etcher/Chromium|Etching of Cr by ICP metal]]
*[[Specific_Process_Knowledge/Etch/IBE&frasl;IBSD Ionfab 300|Sputtering of Al]]
*[[Specific_Process_Knowledge/Etch/IBE&frasl;IBSD Ionfab 300|Sputtering of Cr]]
<br clear="all" />
<br clear="all" />


==Comparison of Aluminium Etch Metodes==
==Comparison of Chromium Etch Methods==


{|border="1" cellspacing="1" cellpadding="3" style="text-align:left;"  
{|border="1" cellspacing="1" cellpadding="3" style="text-align:left;"  
Line 20: Line 24:
|-style="background:silver; color:black"
|-style="background:silver; color:black"
!
!
![[Specific Process Knowledge/Etch/Wet Aluminium Etch|Al wet etch 1]]
![[Specific Process Knowledge/Etch/Wet Chromium Etch|Cr wet etch]]
![[Specific Process Knowledge/Etch/Wet Aluminium Etch|Al wet etch 2]]
![[Specific_Process_Knowledge/Etch/ICP_Metal_Etcher|ICP metal]]
![[Specific_Process_Knowledge/Etch/ICP_Metal_Etcher|Al etch by ICP metal]]
![[Specific_Process_Knowledge/Etch/IBE&frasl;IBSD Ionfab 300|IBE (Ionfab300+)]]
![[Specific_Process_Knowledge/Etch/IBE&frasl;IBSD Ionfab 300|Al sputtering by IBE (Ionfab300+)]]
![[Specific_Process_Knowledge/Etch/DRIE-Pegasus/Pegasus-2|DRIE-Pegasus 2]]
|-
|-


|-
|-
|-style="background:WhiteSmoke; color:black"
|-style="background:WhiteSmoke; color:black"
!Generel description
!General description
|Wet etch of pure Al
|Wet etch of Cr premixed (Chrome etch 18)
|Wet etch of Al + 1.5% Si
|Dry plasma etch of Cr
|Dry plasma etch of Al
|Sputtering of Cr - pure physical etch
|Sputtering of Al - pure physical etch
|Primarily shallow dry etching of silicon but also thin layers of SiO2, TaO2 and Cr
|-
|-


Line 39: Line 43:
!Etch rate range
!Etch rate range
|
|
*~100nm/min (pure Al)
*~150nm/min at room temperature
|
*~60nm/min (Al+1.5% Si)
|
|
*~350 nm/min (depending on features size and etch load)  
*~14 nm/min (depending on features size and etch load)  
|  
|  
*~30nm/min (not tested yet)  
*~30nm/min (not tested yet)  
|
* very slow
|-
|-


Line 51: Line 55:
|-style="background:WhiteSmoke; color:black"
|-style="background:WhiteSmoke; color:black"
!Etch profile
!Etch profile
|
*Isotropic
|
|
*Isotropic
*Isotropic
Line 59: Line 61:
|
|
*Anisotropic (angles sidewalls, typical around 70 dg)
*Anisotropic (angles sidewalls, typical around 70 dg)
|
*Anisotropic (vertical sidewalls)
|-
|-


|-
|-
Line 66: Line 69:
!Substrate size
!Substrate size
|
|
*<nowiki>#</nowiki>1-25 100 mm wafers
*Any size and number that can go inside the beaker in use
|
|
*<nowiki>#</nowiki>1-25 100 mm wafers
* 150 mm wafers
|
* Smaller wafers or pieces on a 150 mm carrier wafer
*smaller pieces on a carrier wafer
*<nowiki>#</nowiki>1 100mm wafers (when set up to 100mm wafers)
*<nowiki>#</nowiki>1 150mm wafers (when set up to 150mm wafers)
|
|
Smaller pieces glued to carrier wafer
Smaller pieces glued to carrier wafer
*<nowiki>#</nowiki>1 50mm wafer
* 50mm wafer
*<nowiki>#</nowiki>1 100mm wafer
* 100mm wafer
*<nowiki>#</nowiki>1 150mm wafer
* 150mm wafer
*<nowiki>#</nowiki>1 200mm wafer
* 200mm wafer
|
* 150mm wafer
* Smaller wafers or pieces on 150mm carrier
|-
|-


|-
|-
|-style="background:WhiteSmoke; color:black"
|-style="background:WhiteSmoke; color:black"
!'''Allowed materials'''
!Allowed materials
|
|
*Aluminium
No restrictions cross contamination wise as long as you use the right beaker and make sure that they are safe to enter in the chemicals
*Silicon
*Silicon Oxide
*Silicon Nitride
*Silicon Oxynitride
*Photoresist
*E-beam resist
|
*Aluminium
*Silicon
*Silicon Oxide
*Silicon Nitride
*Silicon Oxynitride
*Photoresist
*E-beam resist
|
|
*Silicon
*Silicon
Line 123: Line 112:
*Polymers
*Polymers
*Capton tape
*Capton tape
|-
|}
Ething of Chromium can be done either wet or dry. For wet etching please see below on this page. Dry etching can be done either with [[Specific Process Knowledge/Etch/ICP Metal Etcher|ICP]] using Chlorine chemistry or with [[Specific Process Knowledge/Etch/IBE/IBSD Ionfab 300|IBE]] by sputtering with Ar ions.
==Wet etching of Chromium==
[[Image:fumehoodetch-chrom.jpg|300x300px|thumb|Fume hood: positioned in cleanroom 2. <br />Wet Etch of Chromium can take place in a beaker in this fume hood]]
Wet etching of chromium at Danchip is done making your own set up in a beaker in a fume hood - preferably in cleanroom 2 or 4. We have two solution for this:
# HNO<sub>3</sub>:H<sub>2</sub>O:cerisulphate  - 90ml:1200ml:15g - standard at Danchip
# Commercial chromium etch
Etch rate are depending on the level of oxidation of the metal.
====How to mix the Chromium etch 1:====
#Take a beaker and add 15g of cerisulphate.
#Add a little water while stirring - make sure all lumps are gone.
#Add water until 600 ml - keep stirring (use magnetic stirring)
#Add 90 ml HNO<sub>3</sub>
#When the cerisulphate is completely dissolved (clear liquid) you can add the other 600 ml of wafer.
<br clear="all" />
===Overview of the data for the chromium etches===
{| border="1" cellspacing="0" cellpadding="4"
!
! Chromium etch 1
! Chromium etch 2
|-
| '''General description'''
|
|
Etch of chromium
* Silicon
|
* Silicon oxides
Etch of chromium
* Silicon nitrides
* Thin layers of Cr, TaO2
|-
|-
| '''Chemical solution'''
|HNO<sub>3</sub>:H<sub>2</sub>O:cerisulphate  - 90ml:1200ml:15g
|.
|-
| '''Process temperature'''
|Room temperature


|.
|-
| '''Possible masking materials'''
|
Photoresist (1.5 µm AZ5214E)
|
.
|-
|'''Etch rate'''
|
~40-100 nm/min
|
.
|-
|'''Batch size'''
|
1-25 wafers at a time
|
.
|-
|'''Size of substrate'''
|
4" wafers
|
.
|-
|'''Allowed materials'''
|
No restrictions.
Make a note on the bottle of which materials have been processed.
|
.
|-
|}
|}
== Dry etching of chromium ==
On the [[Specific Process Knowledge/Etch/ICP Metal Etcher|ICP Metal Etch]] tool a recipe for chromium is being developed.