Specific Process Knowledge/Etch/DRIE-Pegasus/nanoetch/nano10

The nano1.0 recipe

Recipe nano1.0

Recipe	Gas	C4F8 38 sccm, SF6 52 sccm
	Pressure	4 mTorr, Strike 3 secs @ 15 mTorr
	Power	800 W CP, 50 W PP
	Temperature	10 degs
	Hardware	100 mm Spacers
	Time	120 secs
Conditions	Run ID	1801
	Conditioning	Sequence: Oxygen clean, MU tests, processes, no oxygen between runs
	Mask	1dfhj10 nm zep etched down to 6dgh4 nm

• The results of the nano1.0 recipe
• 
  The 30 nm trenches
• 
  The 60 nm trenches
• 
  The 90 nm trenches
• 
  The 120 nm trenches
• 
  The 150 nm trenches
• File:C4F8 52 sccm, SF6 38 sccm, 4 mTorr, Strike 3 secs @ 15 mTorr, 800 W CP, 50 W PP, 10 degs, 120 secs

Comments

The process looks to be too etch aggressive, not enough passivation. I would consider any or all of the following:

• Decreasing the wafer temperature (make more passivant)
• Increasing C4F8 flow (make more passivant)
• Increasing platen power (make more directional)
• Decreasing coil power (make less etch-aggressive and more directional.

Also, if the tool has Short Funnel and 5mm spacers fitted, it may be too close to the plasma - previous good nano-scale etch result was achieved with Long Funnel and 100mm spacers.

The conditions are similar to the nano-etch conditions for acceptance process C:

	Etch
Gas Flow (sccm)	SF6 38 + C4F8 70
Pressure (mT)	4
APC angle (%)	33.2
Coil power (W)	450
Matching (Forward/ Load)	L/ 33 & T/ 43
HF Platen power (W)	100
Matching (Forward/ Load)	L/ 49 & T/ 53
Time	01:30