ASE Standard Process Test

hrm std tstASEHRM Standard Process Test
CUSTOMER: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SERIAL NO: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PROCESS TYPE: . . . …. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . WAFER CLAMP TYPE: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . WAFER/ CARRIER SIZE: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ASE OPTIONS: LOW FREQUENCY
FIELD TESTS (see note 2 below)
Note 1: This Test phase should not be started until Test Specification C4 document has been completed.
Note 2: For Field tests, please perform sections 1 till 5, 9a & 9b only.
Signed
Date
Checked (Process Test Technician)
Base pressure = …………..T
Pass criteria: <5 x 10-6 Torr Chamber leak-up rate = ………..mT/min (heaters off)
Pass criteria: <0.2 mTorr/min (ideal), <0.5 mTorr/min (target), <1.0 mTorr/min (maximum limit)
Chamber leak-up rate = ………..mT/min (heaters on) Pass criteria: <0.5 mTorr/min (ideal), <0.6 mTorr/min (target), <1.5 mTorr/min (maximum limit)
He leak-up rate = ………..mT/min Pass criteria: <15 mT/min ESC, <15 mT/min WTC, <20 mT/min 200 mm WTC (maximum limit) <10 mT/min ESC, <5 mT/min WTC, <15 mT/min 200 mm WTC (ideal) 95 mm ASE spacers fitted? 20T He backcooling baratron fitted? Foreline heater temperature setpoint = 65°C Chamber block wall heater temperature (HCU3) setpoint = 120°C Confinement chamber heater temperature (HCU7) setpoint = 130°C Gas diffuser heater temperature (HCU7) setpoint = 150°C Self tune on all HCU7 controllers turned off. ALM1 function on all HCU7 controllers = ± 20°C Run O2 clean process on a blank Si wafer for 30 minutes: (40 sccm O2, 40 mT, MSource 800W, Platen 0W, 10°C platen, 10T He backcooling) Signature: . . . . . . . . . . . . . . . . Dat e: . . . . . . . .
ASEHRM Standard Process Test 1. Plasma stability Test
Objective: To demonstrate stable transition between etch and deposition phases without plasma blinks: 1.1 Load blank silicon wafer into the chamber. 1.2 Save the following process as “stab” and run for 14 minutes 59 seconds (62 cycles) , using the following
tables to record process conditions and whether plasma was stable.
Stab Process 1 Etch Step Expected Value Pass. Step Expected Value
Flow: SF6=260sccm , O2=26scc m (9.5s on time + 0s over-run time)
260, 26 sccm 0 sccm
Flow: C4F8= 80sccm (5s on time + 0s over-run time)
0 sccm 80 sccm
Pressure Ranges 3 ~32mT ~13mT
MSource Power = 2.0KW (etch)/300W (deposition) 4 (forward/reflected) ~2000 - 0W ~300 -0W
Load Position / Tune Position - -
30 W
5 W
He flow = . . . . . . sccm , He pressure (set 9.9T) = . . . . T, He LUR = ……………..….mT/min, Wall temperature = 120/130/150ºC (set); Start value:……………………………. End value:…………………….., Platen temperature = 10ºC, Datalog Number: …………………
1 Select passivation step first in recipe 2 Fix APC angle at value which gives ~ 32 mT at end of etch cycle on blank Si wafer 3 Record pressure swings during etch and dep steps i.e. max and min pressures. 4 Record forward and reflected power from screen i.e. if fwd power = 1995W and reflected is 12W then write “1995-12” 5 NOTE. Systems with electrostatic clamping should not display a Vdc reading. Check that the limit in the software is set to 200W.
ASEHRM Standard Process Test 1.3 Plasma stability Record: Was plasma stable or flashing on and off in following steps?
Step Plasma Behaviour 6
Pass/ etch transition
Checks to be performed at generator display/output, not at VDU. For AE 3 KW generators, checks may be performed at the operator station VDU. Note down the minimum value of the reflected power. Examine the datalog files for any discrepancies.
Etch Step Target Pass Step Target Plasma blink time at start of step (<1 s) (<1 s) Number of blinks ( ≤1) ( ≤1) Minimum reflected MSource Power (<20 W) (<40 W)
If the system fails to meet the pass criteria and you change settings and/or perform hardware modifications, return and repeat all previous plasma stability checks (standard tests section C4), to ensure they still meet the targets. Signature: . . . . . . . . . . . . . . . . Dat e: . . . . . . . .
6 E.g. Record stable if plasma shows no evidence of flickering or flashing on/off during each etch or passivation cycle, record blinks if plasma goes off completely and record slight flicker if the plasma flickers during steps or during transitions between steps.
ASEHRM Standard Process Test 2. Wafer Temperature Test
(Only complete if not already carried out in Test Procedure C. If not performed, please copy results from part C into table 2.3.2)
Objective: Ensure correct operation of substrate temperature control system and wafer temperature ≤77°C. 2.1 Standard wafer temperature test. You will need 1 blank Si wafer and temperature dots, ranges 1 till 4. 2.2 Mount temperature dots in the range 40ºC to 110ºC (ranges 1 till 4) at 5 positions on the wafers. The 5 positions are the centre and 4 edges - major flat, opposite major flat, left and right sides. The dots at the edges should be 7 mm from the edge of the wafer. Cover the dots with polyimide tape. The polyimide tape should cover 6 ±±±± 1 mm around the edges of each label. Then pierce the tape with a scalpel/blade to allow trapped air to escape. 2.3.1 Run the following process called ‘temp’ for 15 minutes 8 seconds (79 cycles) and use the following table to
record process conditions:
Temp Process 7 Etch Step Expected Value Pass. Step Expected Value
Flow: SF6=450sccm , O2=45sccm (8.5s on time + 0s over-run time)
450, 45 sccm 0 sccm
Flow: C4F8=200sccm (3s on time + 0s over-run time)
0 sccm 200 sccm
Pressure Ranges 9 ~32-28mT ~14-13mT
MSource Power = 2.2KW (etch)/1.5KW (deposition) 10 (forward/reflected) ~2200 - 0W ~1500 -0W
40 W
20 W
2.5s/2A/………V 0
2.3.2 Record the dots, which have turned black (corresponding to the temperature reached), in the table below: Centre Left Right Major Flat Opposite
Major Flat
ASEHRM Standard Process Test Blank Si wafer
Final temperature
For pass criteria, please see ASE-HRM specification quality document. 2.3.3 Plasma stability Record: Checks to be performed at generator display/output, not at VDU. For AE 3 KW generators, checks may be performed at the operator station VDU. Note down the minimum value of the reflected power. Examine the datalog files for any discrepancies.
If the system fails to meet the pass criteria and you change settings and/or perform hardware modifications, return and repeat all previous plasma stability checks (standard tests section C4), to ensure they still meet the targets.
ASEHRM Standard Process Test 3. Low Temperature Chiller Test
(Only complete if not already carried out in Test P rocedure C)
Objective: Check performance of systems running at sub-zero platen temperatures and to confirm that low temperature operation does not affect He seal. 3.1 To test He leak-up rate (LUR) without RF. Load a blank silicon wafer into the chamber and set He pressure to
9.9 Torr. Record the leak-up rate (LUR) values at the various temperatures shown below. 3.2 Note that chamber LUR tests to be done without a wafer in the chamber and He LUR tests with a wafer in the
chamber. 3.3 When reducing temperature, use a temperature ramp rate of -1°C/min on Huber chillers. On other chillers
change the setpoint as required. After changing chiller temperature, leave time for system to stabilise. On Huber chillers, to reduce temperature press “RAMP” and then “TEMP”. Enter the required temperature and press “ENTER.” Then set the ramping rate by pressing “TIME” and entering the time, which the chiller should take to get to this temperature, followed again, by “ENTER.”
3.4 Please record data in the table below:
Temperature °C He LUR (mT/min) Chamber LUR (mT/min) 20 0
-10 -20
Pass criteria:
Chamber LUR: ≤≤≤≤ 1.5 mT/min (maximum limit - hot) HeLUR: <15 mT/min ESC, <15 mT/min WTC, <20 mT/min 200 mm WTC (maximum limit) <10 mT/min ESC, <5 mT/min WTC, <15 mT/min 200 mm WTC (ideal)
Signature: . . . . . . . . . . . . . . . . Dat e: . . . . . . . .
Objective: To achieve uniform polymer deposition at the expected deposition rate.
4.1 Save the following process as “dep”, and determine fixed APC position by loading blank silicon wafer into
chamber and adjusting APC to get desired pressure with RF on. APC Angle: ……….. °°°°
4.2 With these process parameters run one blank silicon wafer for 3 minutes, using the following tables to record
process conditions. 4.3 As an alternative to scratching the polymer off to measure the step height (as in section 4.5), please place
squares of polyimide tape (1cm square) at 5 positions on the wafer (centre and 4 edges- major flat, opposite major flat, left and right sides).
Note: Major wafer flat must be towards load lock.
Dep Process Recorded process parameters
Flow: C4F8=130sccm (unswitched)
MSource Power = 300W (Auto match): (forward/reflected)
Load
Tune
Load
Tune
Vpp
Vdc
He LUR
Datalog number
4.4 Please record below whether the deposited polymer looks uniform:
ASEHRM Standard Process Test 4.5 Plasma stability Pass Criteria: Checks to be performed at generator display/output, not at VDU. For AE 3 KW generators, checks may be performed at the operator station VDU. Note down the minimum value of the reflected power. Examine the datalog files for any discrepancies.
Value Target Minimum reflected MSource Power (<20 W )
If the system fails to meet the pass criteria and you change settings and/or perform hardware modifications, return and repeat all previous plasma stability checks (standard tests section C4), to ensure they still meet the targets. 4.6 Measure the wafer and record in the table below. Write on the back, the process name, platen power and
system serial number and store in a disposable wafer box. 4.6.1 Note: (a) Edge measurements should be made 5 mm in from the wafer edge. (i.e. 5 mm edge exclusion).
(b) Scratch surface with tweezers and remove debris, to provide step for measurement. Or remove the squares of polyimide tape.
(c) If possible use Tencor P2 profilometer program recipe “Leedep” or P10 profilometer. 4.6.2 Results:
Position Polymer thickness (Å)
For pass criteria, please see ASE-HRM specification quality document.
Note: Uniformity (±…%) = ± {(max – min)/(2 × average)} × 100 Signature: . . . . . . . . . . . . . . . . Dat e: . . . . . . . .
5. Standard SF 6 Etch Rate Tests Objective: To attain Si etch rate of the expected value. 5.1 Using a resist pen or poly tape pattern three new blank silicon wafers as shown below. Note: (a) ~1cm x 1cm squares with edge exclusion of 5 mm LR
ASEHRM Standard Process Test (b) Leave to dry for 10 minutes 5.2 Save the following process as “etch1”, and carry out a 3 minute conditioning run prior to the main test on a
blank silicon wafer. Determine fixed APC position by adjusting APC to get desired pressure with RF on. APC Angle: ……….°°°°
Recipe etch 1; EM1 = 0A Recipe etch 2; EM1 = 2.5A Recipe etch 3; EM1 = 3.4A
ASEHRM Standard Process Test 5.3 With the same process parameters then run the new patterned silicon wafers for 3 minutes each. Use the
following table to record process conditions:
etch1 Process 12 EM1=0A EM1=2.5A EM1=3.4A
Flow: SF6=260sccm (unswitched)
MSource Power = 2000W (Auto match): (forward/reflected)
Load
Tune
Load
Tune
Vpp
Vdc
Platen 10°C
He LUR
Datalog number
5.4 Plasma Stability Record: Checks to be performed at generator display/output, not at VDU. For AE 3 KW generators, checks may be performed at the operator station VDU. Note down the minimum value of the reflected power. Examine the datalog files for any discrepancies.
Value Target Minimum reflected MSource Power (EM1=0A) (<20 W ) Minimum reflected MSource Power (EM1=2.5A) (<20 W ) Minimum reflected MSource Power (EM1=3.4A) (<20 W )
If the system fails to meet the pass criteria and you change settings and/or perform hardware modifications, return and repeat all previous plasma stability checks (standard tests section C4), to ensure they still meet the targets. 5.5 Measure the wafer and record in the table below. Mark on the back, the process name, platen power and
system serial number and store in a disposable wafer box. 5.5.1 Note: (a) Remove resist using acetone soaked wipe.
ASEHRM Standard Process Test (b) Tencor P2 profilometer. Recipe “LeeEtch” or P10 profilometer. (c) Measure etch step 5 mm from wafer edge (i.e. 5 mm edge exclusion).
5.5.2 Record Etch Step in µm:
Position EM1=0A EM1=2.5A EM1=3.4A
Centre
Left
Right
Uniformity (±…%)
Note: Uniformity (±…%) = ± {(max – min)/(2 × average)} × 100 5.5.3 Pass criteria 1: SF6 etch rate at with current on (2.5 A and 3.4 A) should be less than etch rate with no current (0A) i.e. [etch rate (2.5A and 3.4 A) < etch rate (0A)].
Yes No Pass criteria 2: Etch rate difference (2.5 A and 0A) should fall within this margin:
0.2 µm/min ≤ [etch rate (0A)-etch rate (2.5A)] ≤ 0.8 µm/min Does etch rate difference fall within this margin? Yes No For further pass criteria, please see ASE-HRM speci fication quality document. Signature: . . . . . . . . . . . . . . . . Dat e: . . . . . . . .
ASEHRM Standard Process Test 6. Standard Silicon Trench Profile Tests
Objective: To confirm basic switched ASE process meets expected performance level in ‘cold’ or ‘hot’ state. Note: These tests are only carried out on systems before shipment from STS. You will need:
100 mm platen: 2 whole 100 mm STS patterned test wafers 150 mm platen: 2 whole 150 mm STS patterned test wafers + 1x ¼ piece of a 100 mm STS patterned test
wafer (see appendix A) 125 mm and 200 mm platens: 2 whole 100 mm STS patterned test wafers respectively
cool-grease mounted onto photoresist coated silicon wafers.
Note: Use whole STS patterned test wafers with ~4 µµµµm thick mask.
ASEHRM Standard Process Test 6(a): Switched COLD TEST
Ensure chamber is in a cold” state 13 Please tick box if using a quarter piece (e.g. for fault investigation)
6a.1 Measure the resist thickness on the Nanospec before etching, recording the results in the table overleaf. 6a.2 Run the following switch process for 15 minutes 8 seconds (79 cycles) and record the process parameters
in following table:
Switch Process 14 Etch Step Expected Value Pass. Step Expected Value
450, 45 sccm 0 sccm
0 sccm 200 sccm
40 W
20 W
2.5s/2A/……….V 0
13 No RF. should have been run on the system in the previous 2 hours.
ASEHRM Standard Process Test 6a.3 Plasma Stability Record: Checks to be performed at generator display/output, not at VDU. For AE 3 KW generators, checks may be performed at the operator station VDU. Note down the minimum value of the reflected power. Examine the datalog files for any discrepancies.
If the system fails to meet the pass criteria and you change settings and/or perform hardware modifications, return and repeat all previous plasma stability checks (standard tests section C4), to ensure they still meet the targets. Resist Measurements. 6a.4 Re-measure resist thickness after etching and calculate selectivity from the measured depth (below).
Position Pre-etch thickness
C L R MF OMF
6a.5 Cleave wafer through centre and major flat and measure, on a SEM, the dimensions of the cross-section of
two different sized trenches. Please record the results below: Results - switch process on STS test wafer
Feature Size
Depth (µm)
Profile Angle (°)
Undercut (Å/edge)
Scallops (Å)
Centre 40 µm 5 µm Major 40 µm flat 5 µm
Profile angle = 90 – tan-1{(top width – bottom width)/(2 × depth)} RIE lag = (5 µm feature depth)/(40 µm feature depth) 40 µm: Average etch rate =……………µm/min ±……….% 5 µm: Average etch rate =……………µm/min ±……….% RIE lag (5/40) = ………………… For pass criteria, please see ASE-HRM specification quality document. Attach SEMs here. Signature: . . . . . . . . . . . . . . . . Dat e: . . . . . . . .
ASEHRM Standard Process Test 6(b): Switched HOT TEST
Ensure chamber is in a “hot” state 6b.1 Measure the resist thickness on the Nanospec before etching, recording the results in the table overleaf.
Please tick box if using a quarter piece (e.g. for fault investigation) 6b.2 Heating the chamber: Run the following process with 600W power during th e etch and deposition
steps, for 90 minutes on a 2 separate blank Si wafe rs (45 minutes each). 6b.3 Immediately run the following switch process for 15 minutes 8 seconds (79 cycles) and record the process
parameters in following table:
450, 45 sccm 0 sccm
0 sccm 200 sccm
40 W
20 W
2.5s/2A/……….V 0
6b.4 Plasma Stability Record: Checks to be performed at generator display/output, not at VDU. For AE 3 KW generators, checks may be performed at the operator station VDU. Note down the minimum value of the reflected power. Examine the datalog files for any discrepancies.
Etch Step Target Pass Step Target
ASEHRM Standard Process Test Plasma blink time at start of step (<1 s) (<1 s) Number of blinks ( ≤1) ( ≤1) Minimum reflected MSource Power (<20 W) (<40 W)
If the system fails to meet the pass criteria and you change settings and/or perform hardware modifications, return and repeat all previous plasma stability checks (standard tests section C4), to ensure they still meet the targets. Resist Measurements. 6b.5 Re-measure resist thickness after etching and calculate selectivity from the measured depth (below).
C L R MF OMF
6b.6 Cleave wafer through centre and major flat and measure, on a SEM, the dimensions of the cross-section of
Feature Size
Depth (µm)
Profile Angle (°)
Undercut (Å/edge)
Scallops (Å)
Profile angle = 90 – tan-1{(top width – bottom width)/(2 × depth)} RIE lag = (5 µm feature depth)/(40 µm feature depth) 40 µm: Average etch rate =……………µm/min ±……….% 5 µm: Average etch rate =……………µm/min ±……….% RIE lag (5/40) = ………………… Hot-cold wafer-wafer uniformity: 40 µm = ±……….%
5 µm = ±…….….% For pass criteria, please see ASE-HRM specification quality document. Attach SEMs here. Signature: . . . . . . . . . . . . . . . . Dat e: . . . . . . . .
ASEHRM Standard Process Test 7. Deep Silicon Trench Profile Tests
Objective: To confirm that deep switched ASE process meets expected performance level.
Note: Use whole STS patterned test wafers with ~8 µµµµm thick mask. Please tick box if using a quarter piece (e.g. for fault investigation)
7.1 Measure the resist thickness on the Nanospec before etching, recording the results in the table overleaf. 7.2 Run the following deep process for 45 minutes 2 seconds (235 cycles) and record the process parameters
in following table:
Deep Process 24 Etch Step Expected Value Pass. Step Expected Value
Flow: SF6=450sccm, O 2=45sccm (8.5s on time + 0s over-run time)
450, 45 sccm 0 sccm
0 sccm 200 sccm
MSource Power = 2.2KW (etch)/1 .5KW (deposition) 27 (forward/reflected) ~2200 - 0W ~1500 -0W
40 W
20 W
2.5s/2A/……….V 0
ASEHRM Standard Process Test 7.3 Plasma Stability Record: Checks to be performed at generator display/output, not at VDU. For AE 3 KW generators, checks may be performed at the operator station VDU. Note down the minimum value of the reflected power. Examine the datalog files for any discrepancies.
If the system fails to meet the pass criteria and you change settings and/or perform hardware modifications, return and repeat all previous plasma stability checks (standard tests section C4), to ensure they still meet the targets. Resist Measurements. 7.4 Re-measure resist thickness after etching and calculate selectivity from the measured depth (below).
C L R MF OMF
7.5 Cleave wafer through centre and major flat and measure, on a SEM, the dimensions of the cross-section of
two different sized trenches. Please record the results below: Results -Deep process on STS test wafer
Feature Size
Depth (µm)
5 µm Major flat
80 µm 50 µm
5 µm Profile angle = 90 – tan-1{(top width – bottom width)/(2 × depth)} RIE lag = (5 um feature depth)/(80 um feature depth) 80 µm: Average etch rate =……………µm/min ±……….% 50 µm: Average etch rate =……………µm/min ±……….% 5 µm: Average etch rate =……………µm/min ±……….% RIE lag (5/80) = ………………… For pass criteria, please see ASE-HRM specification quality document. If there is grass at the bottom or notching at the top of any trenches, then please perform the altern ative deep etch test in appendix B. Otherwise proceed to sect ion 8. Attach SEMs here. Signature: . . . . . . . . . . . . . . . . Dat e: . . . . . . . .
ASEHRM Standard Process Test 8. Smooth etch process test
Objective: To confirm that smooth switched ASE process meets expected performance level.
Note: Use whole STS patterned test wafers with ~4 µµµµm thick mask. Please tick box if using a quarter piece (e.g. for fault investigation)
8.1 Measure the resist thickness on the Nanospec before etching, recording the results in the table overleaf. 8.2 Run the following smooth process for 5 minutes 15 seconds (63 cycles) and record the process parameters
in following table:
smooth Process 29 Etch Step Expected Value Pass. Step Expected Value
Flow: SF6=450sccm , O2=45sccm (3s on time + 0s over-run time)
450, 45 sccm 0 sccm
0 sccm 200 sccm
45 W
0 W
0s/1A/……….V 0
8.3 Plasma Stability Record: Checks to be performed at generator display/output, not at VDU. For AE 3 KW generators, checks may be performed at the operator station VDU. Note down the minimum value of the reflected power. Examine the datalog files for any discrepancies.
Etch Step Target Pass Step Target
ASEHRM Standard Process Test Plasma blink time at start of step (<1 s) (<1 s) Number of blinks ( ≤1) ( ≤1) Minimum reflected MSource Power (<20 W) (<40 W)
If the system fails to meet the pass criteria and you change settings and/or perform hardware modifications, return and repeat all previous plasma stability checks (standard tests section C4), to ensure they still meet the targets. Resist Measurements. 8.4 Re-measure resist thickness after etching and calculate selectivity from the measured depth (below).
C L R MF OMF
8.5 Cleave wafer through centre and major flat and measure, on a SEM, the dimensions of the cross-section of
two different sized trenches. Please record the results below: Results - smooth process on 'Cronos' wafer
Feature Size
Depth (µm)
Grass? (any trench)
Profile angle = 90 – tan-1{(top width – bottom width)/(2 × depth)} RIE lag = (2 um feature depth)/(5 um feature depth) 5 µm: Average etch rate =……………µm/min ±……….% 2 µm: Average etch rate =……………µm/min ±……….% RIE lag (2/5) = ………………… For pass criteria, please see ASE-HRM specification quality document. Attach SEMs here. Signature: . . . . . . . . . . . . . . . . Dat e: . . . . . . . .
ASEHRM Standard Process Test 9 (a). Pulsing compensation
Objective: To set up pulse generator to achieve required pulse duty cycle. N/A 9a.1 Connect a RF sniffer in series with the RF output (J1) of the LF5 generator and view the signal on an oscilloscope. 9a.2 Run a LF process such as lfhrm (see section 9c) and freeze the signal during the etch cycle. 9a.3 Note down the delay times for various duty cycles and increase the pulse width using the pulse generator as necessary in order to achieve the correct duty cycle. Fill out the table below. Then use these compensated values, if necessary, for all LF pulsed standard tests. Consult a process engineer for clarification if required.
Duty cycle required Compensated on-time required (ms)
Compensated off-time required (ms)
15% (5 ms on, 25 ms off) 20% (5 ms on, 20 ms off) 25% (5 ms on, 15 ms off) 33% (5 ms on, 10 ms off) 50% (5 ms on, 5 ms off)
9 (b) For systems with capability to run platen at low frequency 9b.1 Using lfhrm conditions (see section 9c). Please select low 380KHz option in recipe editor and ensure remote switching enabled on hardware. 9b.2 Unpulsed
Run for 30 minutes and obtain datalog file. Pass criteria: Load and Tune positions are stable and within 20% and 80% limits. OK?
Plasma stability Record: Checks to be performed at generator display/output, not at VDU. For AE 3 KW generators, checks may be performed at the operator station VDU. Etch Step Target Pass Step Target Plasma blink time at start of step (<1 s) (<1 s) Number of blinks (≤ 1) ( ≤ 1) Minimum reflected MSource Power (<5 W) (<15 W)
Datalog file details: 9b.3 Pulsed at 5ms pulse width and 33% duty-cycle Run for 30 minutes and obtain datalog file. Use compensated pulse set-up if necessary, according to section
3(a). Pass criteria: Load and Tune positions are stable and within 20% and 80% limits. OK?
Plasma stability Record: Checks to be performed at generator display/output, not at VDU. For AE 3 KW generators, checks may be performed at the operator station VDU. Etch Step Target Pass Step Target Plasma blink time at start of step (<1 s) (<1 s) Number of blinks (≤ 1) ( ≤ 1) Minimum reflected MSource Power (<20 W) (<40 W)
Datalog file details: Signature: . . . . . . . . . . . . . . . . Dat e: . . . . . . . .
ASEHRM Standard Process Test 9 (c). SOI test
Objective: To confirm that SOI feature controls notching at Si/oxide interface. N/A Note: Use 1/8 piece of SOI wafer (20 µm thick SOI, 150 mm diameter test wafers) mounted onto a resist coated oxide carrier with cool-grease.
Please tick box if using a 1/16 piece (e.g. for fau lt investigation)
9c.1 Measure the resist thickness on the Nanospec before etching, recording the results in the table overleaf. 9c.2 Run the following lfhrm process for 5 minutes 40 seconds = 68 cycles (estimated ~20% overetch) and
record the process parameters in following table:
lfhrm Process 34 Etch Step Expected Value Pass. Step Expected Value
Flow: SF6=450sccm , O2=45sccm (3s on time + 0s over-run time)
450, 45 sccm 0 sccm
0 sccm 100 sccm
MSource Power = 3.0KW (etch)/1.0W (deposition) 37 (forward/reflected) ~3000 - 0W ~1000 -0W
(LF 5 ms 20% duty cycle)
45 W
0 W
1A 0
He flow = . . . . . . sccm , He pressure (set 9.9T) = . . . . T, He LUR = ……………..….mT/min, Wall temperature = 120/130/150ºC(set); Start value:……………………………. End value:…………………….., Platen temperature = 10ºC, Datalog Number: …………………
9c.3 Plasma Stability Record: Checks to be performed at generator display/output, not at VDU. For AE 3 KW generators, checks may be performed at the operator station VDU. Note down the minimum value of the reflected power. Examine the datalog files for any discrepancies.
ASEHRM Standard Process Test Etch Step Target Pass Step Target Plasma blink time at start of step (<1 s) (<1 s) Number of blinks ( ≤1) ( ≤1) Minimum reflected MSource Power (<20 W) (<40 W)
If the system fails to meet the pass criteria and you change settings and/or perform hardware modifications, return and repeat all previous plasma stability checks (standard tests section C4), to ensure they still meet the targets. Resist Measurements. 9c.4 Re-measure resist thickness after etching and calculate selectivity from the measured depth (below).
Centre Edge
9c.5 Cleave wafer through centre and major flat and measure, on a SEM, the dimensions of the cross-section of
the 3 µm sized trenches. Please record the results below: Results -lfhrm process
Feature Size
Depth (µm)
3 µm
Profile angle = 90 – tan-1{(top width – bottom width)/(2 × depth)} Average etch rate (including overetch) =……………µm/min For pass criteria, please see ASE-HRM specification quality document. Notch width/edge should be ≤≤≤≤0.35 µµµµm. If notch width/edge > 0.35 µm, is depth <20 µm?
Yes then proceed to section 10.
No then perform test in appendix C before proceeding to section 10.
Attach SEMs here. Signature: . . . . . . . . . . . . . . . . Dat e: . . . . . . . .
ASEHRM Standard Process Test 10. Final Checks
10.1 Final Chamber Vacuum Check: 10.2 Chamber base pressure (<5 x 10-6 Torr) . . . . . . . . . . Torr 10.3 Chamber leak-up rate (<1.0 mTorr/min) . . . . . . . . . mTorr/ min (with heaters on) [from base pressure averaged over a minimum of 3 minutes] Signature: . . . . . . . . . . . . . . . . Dat e: . . . . . . . . 10.4 Is ECN Activity Sheet up to date (i.e. all ECNs affecting machine listed & signed off if completed on machine). YES 10.5 List all outstanding ECNs that have yet to be actioned: . . . . . . . . . . . . . . . . . . . . . . . . . . . . Signature: . . . . . . . . . . . . . . . . Dat e: . . . . . . . .
10.6 Please record all faults on the process fault sheet or in a notepad document and attach a hard-copy to this document on handover. 10.7 Please summarise the results in the table provided in the ASE-HRM summary quality document QD000118.
Specifications for 100mm and 150 mm systems can be found in the ASE-HRM specification quality document TS000012.
10.8 Provided all sections of this document & the Safety Certificate have been completed the machine may be handed over to the Process Department. Signature: . . . . . . . . . . . . . . . . Dat e: . . . . . . . .
ASEHRM Standard Process Test APPENDIX A: Switched COLD TEST
This test is only to be performed on 150 mm systems . Please use a ¼ piece of a 100 mm STS patterned test wafer mounted on a 150 mm resist coated carrier. Ensure chamber is in a cold” state 39.
A.1 Measure the resist thickness on the Nanospec before etching, recording the results in the table overleaf. A.2 Run the following switch process for 15 minutes 8 seconds (79 cycles) and record the process parameters
in following table:
450, 45 sccm 0 sccm
0 sccm 200 sccm
40 W
20 W
2.5s/2A/……….V 0
39 No RF. should have been run on the system in the previous 2 hours.
ASEHRM Standard Process Test A.3 Plasma Stability Record: Checks to be performed at generator display/output, not at VDU. For AE 3 KW generators, checks may be performed at the operator station VDU. Note down the minimum value of the reflected power. Examine the datalog files for any discrepancies.
If the system fails to meet the pass criteria and you change settings and/or perform hardware modifications, return and repeat all previous plasma stability checks (standard tests section C4), to ensure they still meet the targets. Resist Measurements. A.4 Re-measure resist thickness after etching and calculate selectivity from the measured depth (below).
C L R MF OMF
A.5 Cleave wafer through centre and major flat and measure, on a SEM, the dimensions of the cross-section of
Feature Size
Depth (µm)
Profile Angle (°)
Undercut (Å/edge)
Scallops (Å)
Profile angle = 90 – tan-1{(top width – bottom width)/(2 × depth)} RIE lag = (5 µm feature depth)/(40 µm feature depth) 40 µm: Average etch rate =……………µm/min ±……….% 5 µm: Average etch rate =……………µm/min ±……….% RIE lag (5/40) = ………………… For pass criteria, please see ASE-HRM specification quality document. Attach SEMs here.
ASEHRM Standard Process Test Signature: . . . . . . . . . . . . . . . . Dat e: . . . . . . . .
APPENDIX B - ALTERNATIVE DEEP ETCH TEST This test is only to be run if deep etch test 7a fa ils. N/A
B.1 Run the following deep process for 45 minutes 2 seconds (235 cycles) and record the process parameters
in following table:
Deep Process 45 Etch Step Expected Value Pass. Step Expected Value
Flow: SF6=450sccm (8.5s on time + 0s over-run time)
450 sccm 0 sccm
0 sccm 200 sccm
(forward/reflected)
2.5s/2A/……….V 0
ASEHRM Standard Process Test B.2 Plasma Stability Record: Checks to be performed at generator display/output, not at VDU. For AE 3 KW generators, checks may be performed at the operator station VDU. Note down the minimum value of the reflected power. Examine the datalog files for any discrepancies.
If the system fails to meet the pass criteria and you change settings and/or perform hardware modifications, return and repeat all previous plasma stability checks (standard tests section C4), to ensure they still meet the targets. Resist Measurements. B.3 Re-measure resist thickness after etching and calculate selectivity from the measured depth (below).
C L R MF OMF
B.4 Cleave wafer through centre and major flat and measure, on a SEM, the dimensions of the cross-section of
two different sized trenches. Please record the results below: Results -Deep process on STS test wafer
Feature Size
Depth (µm)
5 µm Major flat
80 µm 50 µm
5 µm Profile angle = 90 – tan-1{(top width – bottom width)/(2 × depth)} RIE lag = (5 um feature depth)/(80 um feature depth) 80 µm: Average etch rate =……………µm/min ±……….% 50 µm: Average etch rate =……………µm/min ±……….% 5 µm: Average etch rate =……………µm/min ±……….% RIE lag (5/80) = ………………… Attach SEMs here. Signature: . . . . . . . . . . . . . . . . Dat e: . . . . . . . .
APPENDIX C: CHECK FOR LF ETCH RATE This test is only to be performed if test 9c fails (i.e. notch width/edge > 0.35 µµµµm and SOI depth >20 µµµµm)
N/A
C.1 Run the following lfhrm process for 5 minutes 40 seconds on an STS patterned test wafer (not SOI) and
record the process parameters in following table:
ASEHRM Standard Process Test lfhrm Process 50 Etch Step Expected Value Pass. Step Expected
Value Flow: SF6=450sccm , O2=45sccm (3s on time + 0s over-run time)
450, 45 sccm 0 sccm
0 sccm 100 sccm
MSource Power = 3.0KW (etch)/1.0W (deposition) 53 (forward/reflected) ~3000 - 0W ~1000 -0W
(LF 5 ms 20% duty cycle)
45 W
0 W
1A 0
He flow = . . . . . . sccm , He pressure (set 9.9T) = . . . . T, He LUR = ……………..….mT/min, Wall temperature = 120/130/150ºC(set); Start value:……………………………. End value:…………………….., Platen temperature = 10ºC, Datalog Number: …………………
ASEHRM Standard Process Test C.2 Plasma Stability Record: Checks to be performed at generator display/output, not at VDU. For AE 3 KW generators, checks may be performed at the operator station VDU. Note down the minimum value of the reflected power. Examine the datalog files for any discrepancies.
If the system fails to meet the pass criteria and you change settings and/or perform hardware modifications, return and repeat all previous plasma stability checks (standard tests section C4), to ensure they still meet the targets. Resist Measurements. C.3 Re-measure resist thickness after etching and calculate selectivity from the measured depth (below).
Centre Edge
C.4 Cleave wafer through centre and major flat and measure, on a SEM, the dimensions of the cross-section of
the 3 µm sized trenches. Please record the results below: Results -lfhrm process
Feature Size
Depth (µm)
3 µm

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ASE Standard Process Test