View source for STS APS DGRIE/Processes/LNF Polymer

{{Infobox process
|technology = RIE
|material = Polyimide
|mask = Photoresist, SiO<sub>2</sub>, Aluminum
|gases = O<sub>2</sub>, He
|created = October 2020
|modified =  
|authors = Shawn Wright & Kevin Owen
}} [[Category:Processes]] [[Category:RIE]]

[[{{PAGENAME}}|{{SUBPAGENAME}}]] is an O<sub>2</sub> based plasma etch for thin film polymers (e.g. [[polyimide]], [[parylene]]).

==Procedure==
Follow the instructions in the tool [[{{ROOTPAGENAME}}#Standard operating procedure|operating procedure]] and select ''LNF Polymer'' from the supported processes folder.

==Parameters==
{| class="wikitable" border="1" style="text-align: center"
|-
!Parameter
!Main Etch
|-
|Pressure
|5 mTorr
|-
|ICP Power
|2000 W
|-
|Bias Power
|30 W
|-
|O<sub>2</sub> Flow
|90 sccm
|-
|He Flow
|100 sccm
|}

==Characterization==
<!-- Use this section to put any characterization data. Examples in headings below. Can go in separate sections or a bulleted list.-->

===Etch Rate===
*Polyimide: 920 nm/min
*SPR 220: 963 nm/min
*Parylene: 1.3 µm/min (user reported)

===Uniformity===
Not tested.

===Mask selectivity===
*Platinum: ~1.5 nm/min
*SiO<sub>2</sub>: 28 nm/min
*Aluminum: < 2 nm/min (varies with etch time; e.g. 30 sec or less is higher, ~4 nm/min) (user reported)

==Limitations==
Oxygen plasmas are predominantly isotropic; the specific isotropy ratio has not been measured for this process. Standard photoresist masks are not recommended, since they are polymers and will also etch quickly with this process. However, there are limitations to what type of hard mask is acceptable, so please create a helpdesk ticket to discuss your process with a tool engineer.

==Qualification==
None at this time.