Specific Process Knowledge/Etch/ICP Metal Etcher: Difference between revisions

Revision as of 15:10, 23 February 2011

Etching of nanostructures in silicon using the ICP Metal Etcher

**The starting point**
Break	Gas	Cl₂ 20 sccm
	Pressure	2 mTorr, Strike 3 secs @ 5 mTorr
	Power	600 W CP, 200 W PP
	Temperature	20 degs
	Hardware	100 mm Spacers
	Time	15 secs
Main	Gas	HBr 20 sccm
	Pressure	2 mTorr, Strike 3 secs @ 5 mTorr
	Power	900 W CP, 50 W PP
	Temperature	20 degs
	Hardware	100 mm Spacers
	Time	? secs

ER 200 nm/min, 3:1 over resist. Vertical profile. To improve selectivity to oxide under-layers you can add a small amount of O2 ( e.g 2 sccm if the MFC is small enough). This should not give an undercut.

Standardization images of the shallolr recipe
The profile of a 2 $\mu$ m trench
The profile of a 50 $\mu$ m trench

@@ Line 2: / Line 2: @@
-=== s ===
-Two recipes have been optimized for the ASE. Their specification is on a 10 % etch load wafer with trenches.
-* '''Shallolr''': The shallow etch process will etch a 2 <math>\mu</math>m opening down to make a 20 <math>\mu</math>m trench.
-* '''Deepetch''': The deep etch process will etch a 50 <math>\mu</math>m opening down to make a 300 <math>\mu</math>m trench.
-The standardization procedure on the ASE covers these two etches.
-== Recipes on the ASE ==
-=== Shallolr ===
-The shallolr recipe is designed to etch features (with sizes above 1 <math>\mu</math>m) in silicon down to a depth that ranges from a few microns to some 50 microns. (If you need to etch deeper use Deepetch or more shallow, see Nanoetches.) It is specified to etch a 2 <math>\mu</math>m wide trench down to a depth of 20 <math>\mu</math>m on a wafer that has a global/local etch opening density of 10%.
-The recipe is given below.
 {| border="2" cellpadding="2" cellspacing="1"
@@ Line 41: / Line 27: @@
 ! rowspan="6" align="center"| Main
 | Gas
-| Cl<sub>2</sub> 20 sccm
+| HBr 20 sccm
 |-
 | Pressure
@@ Line 47: / Line 33: @@
 |-
 | Power
-| 600 W CP, 200 W PP
+| 900 W CP, 50 W PP
 |-
 | Temperature
@@ Line 56: / Line 42: @@
 |-
 | Time
-| 15 secs
+| ? secs
 |-
 |}
+ER 200 nm/min,  3:1 over resist.  Vertical profile.   To improve selectivity to oxide under-layers you can add a small amount of O2   ( e.g 2 sccm  if the MFC is small enough).    This should not give an undercut.
-The process runs for 31 cycles (5:56 mins). The fact that it's Bosch process is clear from the scallops on the sidewalls - one should be able to count 31 of them.
 <gallery caption="Standardization images of the shallolr recipe" widths="300px" heights="300px" perrow="2">