Specific Process Knowledge/Lithography/CSAR

Resist	Polarity	Manufacturer	Comments	Technical reports	Spinner	Developer	Rinse	Remover	Process flows (in docx-format)
CSAR	Positive	AllResist	Standard positive resist, very similar to ZEP520.	Allresist_CSAR62_English.pdf‎,, CSAR_62_Abstract_Allresist.pdf‎	Manual Spinner 1 (Laurell), Spin Coater Labspin	X AR 600-54/6, MIBK:IPA	IPA, H2O	1165 Remover	Process_Flow_CSAR.docx‎

Simple e-beam pattern in this resist has been tested, the results showed on this page. If you have questions to the process or wish to use this e-beam resist, please contact Tine Greibe at tigre@danchip.dtu.dk.

Process Flow

Test of Chemically Semi-Amplified Resist (CSAR); a positive e-beam resist from AllResist (AR-P 6200-2).

Equipment	Process Parameters	Comments
Pretreatment
4" Si wafers	No Pretreatment
Spin Coat
Spin Coater Manual, LabSpin, A-5	AR-P 6200/2 AllResist E-beam resist 60 sec at various spin speed. Acceleration 4000 s-2, softbake 1 - 5 min at 150 deg Celcius	Disposal pipette used; clean by N2-gun before use. Use approximately 1.5 ml per 4" wafer, never use a pipette twice. Softbake is not a crucial step, see e-mail correspondence with AllResist here.
Characterization
Ellipsometer VASE B-1	9 points measured on 100 mm wafer	ZEP program used; measured at 70 deg only
E-beam Exposure
JEOL 9500 E-beam writer, E-1	Dosepattern 15nm - 100nm, dose 120-280 muC/cm2	Virtual chip mark height detection (CHIPAL V1) used in corner of every dose array
Development
Fumehood, D-3	60 sec in X AR 600-54/6, 60 sec rinse in IPA, N2 Blow dry	Gentle agitation while developing. After developing, wafer is immersed in beaker with IPA, subsequently blow dried with N2 gun.
Characterization
Zeiss SEM Supra 60VP, D-3	2-3 kV, shortest working distance possible, chip mounted with Al tape	The wafers are diced into smaller pieces and sputter coated with Pt at DTU CEN before SEM inspection; please contact Ramona Valentina Mateiu for further information.

Spin Curves

The thickness is measured on VASE Ellipsometer using a simple Cauchy model for a transparent polymer on Si. The measurements are performed at one incidence angle (70 degrees) only. 9 points on each 4" wafer has been measured; the standard deviation thus representing the homogeinity of the film on the 4" wafers.

Dosepattern has been e-beam exposured and SEM inspected on those wafers marked by silver gray.

AllResist AR-P 6200/2 spinning on Spin Coater: Manual LabSpin A-5, TIGRE, 09-04-2014. Softbake 5 min @ 150 degC.
Spin Speed [rpm]	Acceleration [1/s2]	Thickness [nm]	St Dev
2000	4000	225.98	0.97
3000	4000	194.00	0.6
4000	4000	169.57	0.32
5000	4000	151.47	0.26
6000	4000	142.38	0.41
7000	4000	126.59	0.36

AllResist CSAR on Spin Coater: Manual LabSpin A-5, TIGRE, 16-06-2014. Softbake 2 min @ 150 degC.
Spin Speed [rpm]	Acceleration [1/s2]	Thickness [nm]	St Dev
3000	4000	201.61	1.20
4000	4000	173.89	0.64
5000	4000	155.91	0.65

AllResist CSAR 1:1 in anisole, Spin Coater: Manual LabSpin A-5, TIGRE, 16-06-2014. Softbake 2 min @ 150 degC.
Spin Speed [rpm]	Acceleration [1/s2]	Thickness [nm]	St Dev
2000	4000	83.48	0.49
3000	4000	67.12	0.41
4000	4000	58.64	0.44
5000	4000	53.13	0.39
6000	4000	48.76	0.38

Dosetests

wafer 6.13

Process	Equipment	Parameters	Date and initials
Resist	Fumehood D-3	AR-P 6200/2 AllResist E-beam resist diluted 1:1 in anisole	Bottled opened 16-06-2014 TIGRE
Spin Coat	Spin Coater LabSpin A-5	1 min @ 6000 rpm, 2000 1/s2, softbake 1 min @ 150 degC, thickness ~50nm	27-08-2014 TIGRE
E-beam exposure	JEOL 9500 E-2	0.2 nA, aperture 5, dose 180-420 muC/cm2, Shot pitch 7-27 nm	27-08-2014 TIGRE
Develop	Fumehood D-3	SX-AR 600-54/6 60 sec, 30 sec IPA rinse	28-08-2014 TIGRE
Sputter Coat	Cressington 208HR, DTU CEN	3-5 nm Pt, sputtering	29-08-2014 TIGRE
Characterization	Zeiss SEM Supra 60VP, D-3	3 kV, WD below 4mm, conducting tape close to pattern	29-08-2014 TIGRE

Wafer 6.13, 100 nm exposed pattern, shot pitch 7 nm
300 [muC/cm2]							ACHK NOT READY

Wafer 6.13, 50 nm exposed pattern, shot pitch 7 nm
270 [muC/cm2]						ACHK NOT READY
300 [muC/cm2]						ACHK NOT READY

Wafer 6.13, 30 nm exposed pattern, shot pitch 7 nm
240 [muC/cm2]					ACHK NOT READY
270 [muC/cm2]					ACHK NOT READY
300 [muC/cm2]					ACHK NOT READY

Wafer 6.13, 20 nm exposed pattern, shot pitch 7 nm
270 [muC/cm2]			ACHK NOT READY
300 [muC/cm2]			ACHK NOT READY

wafer 4.09

The e-beam exposures presented here are written with 'SHOT A,10', i.e. a shot pitch of 5nm; this pitch works very well for large structures but not so well for 20nm or below. To illustrate this, ACHK screenshot are presented along with SEM inspection picures.

Process	Equipment	Parameters	Date and initials
Resist	Fumehood D-3	AR-P 6200/2 AllResist E-beam resist diluted 1:1 in anisole	16-06-2014 TIGRE
Spin Coat	Spin Coater LabSpin A-5	1 min @ 5000 rpm, 4000 1/s2, softbake 2 min @ 150 degC, thickness ~53nm	16-06-2014 TIGRE
E-beam exposure	JEOL 9500 E-2	0.2 nA, aperture 5, dose 207-242 muC/cm2, SHOT A,10	02-07-2014 TIGRE
Develop	Fumehood D-3	SX-AR 600-54/6 60 sec, 60 sec IPA rinse	08-07-2014 TIGRE
Sputter Coat	Cressington 208HR, DTU CEN	3-5 nm Pt, sputtering	09-07-2014 TIGRE
Characterization	Zeiss SEM Supra 60VP, D-3	3 kV, WD below 4mm, conducting tape close to pattern	09-07-2014, TIGRE

SEM inspection of wafer 4.09, 50 nm exposed pattern, shot pitch 5 nm
230 [muC/cm2]

SEM inspection of wafer 4.09, 30 nm exposed pattern, shot pitch 5 nm
219 [muC/cm2]
230 [muC/cm2]
242 [muC/cm2]

SEM inspection of wafer 4.09, 20 nm exposed pattern, shot pitch 5 nm
230 [muC/cm2]
242 [muC/cm2]
253 [muC/cm2]

SEM inspection of wafer 4.09, 15 nm exposed pattern, shot pitch 5 nm
253 [muC/cm2]
276 [muC/cm2]

140 nm CSAR

Process	Equipment	Parameters	Date and initials
Resist	Fumehood D-3	AR-P 6200/2 AllResist E-beam resist	2013 (bottle opened)
Spin Coat	Spin Coater LabSpin A-5	1 min @ 6000 rpm, 4000 1/s2, softbake 5 min @ 150 degC, thickness ~143nm	09-04-2014 TIGRE
E-beam exposure	JEOL 9500 E-2	2 nA, aperture 5, dose 207-242 muC/cm2, SHOT A,10	10-04-2014 TIGRE
Develop	Fumehood D-3	SX-AR 600-54/6 60 sec, 60 sec IPA rinse	April/May-2014 TIGRE
Sputter Coat	Cressington 208HR, DTU CEN	2-3 nm Pt, sputtering	22-05-2014 TIGRE
Characterization	Zeiss SEM Supra 60VP, D-3	2 kV, WD below 4mm, conducting tape close to pattern	06-06-2014, TIGRE

50nm

dose [muC/cm2]	207	219	230	242

30nm

dose [muC/cm2]	207	219	230	242

20nm

dose [muC/cm2]	230	242	253