Specific Process Knowledge/Etch/Wet Aluminium Etch: Difference between revisions

@@ Line 1: / Line 1: @@
 ==Wet Aluminium Etch==
 [[Image:Wet_Al_etch.jpg|300x300px|thumb|Wet Aluminium Etch: Positioned in cleanroom 4]]
+Wet etching of aluminium is done with two different solutions:
+# H<math>_2</math>O:H<math>_3</math>PO<math>_4</math>  1:2 at 50 <sup>o</sup>C
+# Pre-mixed etch solution: PES 77-19-04 at 20 <sup>o</sup>C
+===Comparing the two solutions===
+{| border="1" cellspacing="0" cellpadding="4" align="left"
+!
+! Aluminium Etch 1
+! Aluminium Etch 2
+|-
+|General description
+|
+Etch of pure aluminium
+|
+Etch of aluminium + 1.5% Si
+|-
+|Chemical solution
+|H<math>_2</math>O:H<math>_3</math>PO<math>_4</math>  1:2
+|PES 77-19-04
+|-
+|Process temperature
+|50 <sup>o</sup>C
+|20 <sup>o</sup>C
+|-
+|Possible masking materials:
+|
+Photoresist (1.5 µm AZ5214E)
+|
+Photoresist (1.5 µm AZ5214E)
+|-
+|Etch rate
+|
+~100 nm/min (Pure Al)
+|
+~60(??) nm/min
+|-
+|Batch size
+|
+-25 wafers at a time
+|
+-25 wafer at a time
+|-
+|Size of substrate
+|
+" wafers
+|
+" wafers
+|-
+|Allowed materials
+|
+*Aluminium
+*Silicon
+*Silicon Oxide
+*Silicon Nitride
+*Silicon Oxynitride
+*Photoresist
+*E-beam resist
+|
+*Aluminium
+*Silicon
+*Silicon Oxide
+*Silicon Nitride
+*Silicon Oxynitride
+*Photoresist
+*E-beam resist
+|-
+|}