background image

36 

Tergeo plasma cleaner operator’s manual 

Revision: B3, Year 2020

 

 

8.14 Process uniformity in the chamber.  

There  are  many factors that can impact the process uniformity. Uniformity can be influenced by the 
plasma radical production and recombination, gas transportation and sample loading effect. The gas 
comes in from the holes on the front right side of the chamber. Uniformity will be better if the samples 
is placed far away from the gas entrance port,  especially for remote mode plasma processing. We 
recommend placing the sample around or beyond the middle point in the chamber.  

For remote mode plasma, place the samples deeper into the chamber. If necessary, place the samples 
vertically to improve the uniformity. In the remote mode plasma processing, the atomic oxygen and 
hydrogen radicals are generated in the remote plasma source, the radicals will then enters the main 
chamber. If the pressure in the main chamber is too high, the atomic radicals will recombine to become 
more stable molecules and loss the efficacy.  At the pressure of 1.0  Torr, the mean free path is only 
around  0.1mm. The mean free path will increase to 1mm  when the pressure is reduced to 0.1 Torr. 
Therefore, the density of the radicals will gradually reduce from the front of the chamber (the holes for 
the remote plasma source) to the back of the chamber (pumping port). Placing the samples vertically 
deep in the chamber can improve the process uniformity for remote mode plasma processing. In the 
remote mode plasma process, keep the chamber pressure below 1.0Torr to reduce the recombination 
loss. Otherwise, there won’t have much reactive radicals left beyond the entrance port of the remote 
plasma source.  

The uniformity of the direct mode plasma is usually better than the remote mode plasma because the 
radicals are produced throughout the chamber space. For uniformity critical process, place the sample 
flat on the quartz sample holder at a location around or slightly over the middle point of the chamber.  

 

 

 

 

 

 

 

 

 

 

 

Summary of Contents for Tergeo-EM

Page 1: ...ma cleaner operator s manual Revision B3 Year 2020 Operator s Manual Tergeo plasma cleaner PIE SCIENTIFIC LLC Address 3209 Whipple Road Union City CA 94587 U S A Tel 1 510 788 2439 Email support piesc...

Page 2: ...entific LLC Every effort has been made to ensure that the data given in this document is accurate The information figures tables specifications and schematics contained herein are subject to change wi...

Page 3: ...ons 7 5 3 Electrical ratings 8 5 4 Environmental conditions 9 5 5 IEC 61010 1 2010 electrical safety conformity certificate 10 5 6 UL CSA 61010 1 conformance certificate from TUV Rheinland 11 5 7 UL J...

Page 4: ...4 3 Set up the timer 27 8 4 4 Change the cleaning mode 27 8 4 5 Set up the rf power supply 27 8 4 6 Stop the process manually 28 8 4 7 Vent the chamber 28 8 5 Set up recipes in recipe library 28 8 6...

Page 5: ...gnite 41 10 4 Auto impedance tuning fails 41 10 5 Recipe execution stuck in the pumping down state 42 10 6 Gas flow rate can t reaching the set value 42 10 7 Flow controller oscillate at the set point...

Page 6: ...ote plasma cleaning mode 15 Figure 4 pulsed operation mode 15 Figure 5 Front view of Tergeo plasma cleaner 19 Figure 6 sample chamber assembly 19 Figure 7 Front cap for sample chamber 20 Figure 8 back...

Page 7: ...ygen mixture with oxygen concentration level lower than 25 To pump highly concentrated oxygen inert PFPE pump oil such as Krytox or Fomblin should be used instead The oil free dry pump is also compati...

Page 8: ...or of the vacuum chamber The front door will seal automatically during pumping down even if it feels loose 14 Do not open the front door if the chamber is still under the vacuum 15 Equipment can be he...

Page 9: ...ld be equal or higher than 10amps 5 4 Environmental conditions 1 The recommended condition for operation temperature range is 0 30C humidity 10 70 RH 2 The recommended conditions for transportation an...

Page 10: ...10 Tergeo plasma cleaner operator s manual Revision B3 Year 2020 5 5 IEC 61010 1 2010 electrical safety conformity certificate...

Page 11: ...11 Tergeo plasma cleaner operator s manual Revision B3 Year 2020 5 6 UL CSA 61010 1 conformance certificate from TUV Rheinland...

Page 12: ...12 Tergeo plasma cleaner operator s manual Revision B3 Year 2020 5 7 UL Japan rf emission conformity certificate...

Page 13: ...plasma system consists of the following components a sample chamber a remote plasma source a rf power supply rf electrodes rf antennas a gas delivery system plasma sensors system control electronics...

Page 14: ...on bombardment Immersion mode plasma treatment is mainly used for high speed plasma etching and surface activation Figure 2 immersion mode plasma cleaning If remote plasma source option is purchased T...

Page 15: ...urther reduce the average plasma power and change discharge chemistry If pressure is too high or rf power is too low plasma may fail to ignite in pulsed operation mode If plasma fails to ignite please...

Page 16: ...process gasses The plasma emission intensity for electronegative oxygen gas is usually very low The plasma emission intensity for argon gas is usually very high For the plasma sensor to measure low i...

Page 17: ...m pump Before operating the rotary vane vacuum pump please make sure the oil has been filled in the tank The oil level must be within the min and max levels indicated on the oil window Please check th...

Page 18: ...ump If the plasma cleaner is connected to the exhaust port on the vacuum pump the pressure in the vacuum hose will rise to a very high pressure The high pressure will damage the pump valve in the plas...

Page 19: ...ront surface of the o ring and the glass door regularly with lint free wipes If the o ring has been taken out of the o ring grooves then please reapply the vacuum grease on the o ring and inside the o...

Page 20: ...tlet Connects to pump Pump power inlet connects to utility power Venting port with an optional dust particle filter Process gas input If the untreated room air is directly used to vent the chamber or...

Page 21: ...ossible use PTFE high vacuum grease to lightly grease the o ring for better vacuum seal 5 Insert the quartz sample holder plate into the sample chamber Please refer to Figure 6 sample chamber assembly...

Page 22: ...bing will reduce The plasma intensity for the pure O2 plasma will increase significantly due to the N2 gas impurity The color of the pure O2 plasma should be pure white If the gas is contaminated with...

Page 23: ...pressure to below 10 psi Connect the gas bottle and the plasma cleaner with inch PTFE Teflon gas tubing Then set the gas flow rate to 90sccm on the corresponding gas input channel on the touchscreen u...

Page 24: ...s input pressure above 15 psig For potentially dangerous gas such as hydrogen please reduce the gas input pressure to 5 PSI It is recommended to turn off the power to the plasma cleaner if user doesn...

Page 25: ...certain application is finalized the user should save it in the recipe library During the course of the plasma cleaning the gas composition and chamber pressure may change because of outgassing from...

Page 26: ...ain screen is divided into three sub panels The left panel shows the current recipe and job sequence to be executed The middle panel shows the system status manual control buttons and inputs The right...

Page 27: ...system screen It is suggested to use plasma on event as the timer trigger If the plasma is too weak to be detected by the plasma sensor the user can then use rf on event as the timer trigger 8 4 4 Ch...

Page 28: ...ing sound stops Then rotate the front cap in CCW direction and pull it out The automatic venting sequence will not vent the hose section between the vacuum pump and the plasma chamber If the user want...

Page 29: ...io is calculated as N 255 where N is the number specified in the recipe Gas flow rate can be adjusted from 0 to 100 sccm If input gas is at atmospheric pressure the maximum gas flow rate that can be a...

Page 30: ...nd always load the recipes saved in the library 8 6 2 Turn on the vacuum pump If the vacuum pump is not controlled by the plasma cleaner please turn on the vacuum pump manually If the vacuum pump is p...

Page 31: ...p down the chamber until background pressure reaches the upper limit pressure set in the system screen then the system will flush the chamber with the process gas After the chamber has been flushed wi...

Page 32: ...ake sure the vacuum pump is on 3 Click Run Job button to start the job The execution steps of each recipe is the same as the steps mentioned in the previous section 8 7 Tune the impedance If the plasm...

Page 33: ...mber under vacuum when it is in the idle state by clicking the finish up button after each use It will pump down the plasma sample chamber and place system in the idle state When the system is first i...

Page 34: ...argon carrier gas For pure hydrogen please keep gas flow rate below 1 0sccm Otherwise the vacuum pressure may not be stable 8 12 How to create extremely weak oxygen plasma for some critical biopolymer...

Page 35: ...e of the process gas should be 99sccm for the gas channel to be cleaned The duration can be from 3 minutes to 10 minutes depending on the length of the gas tubing Run the gas line cleaning recipe if t...

Page 36: ...essure in the main chamber is too high the atomic radicals will recombine to become more stable molecules and loss the efficacy At the pressure of 1 0 Torr the mean free path is only around 0 1mm The...

Page 37: ...ation period Upper limit pressure before cleaning starts specifies the maximum background pressure allowed for plasma cleaning to start during a recipe execution session If there is a vacuum leak or t...

Page 38: ...e the plasma cleaning recipe finishes Calibrate autotuner It will find the zero and the maximum positions for the auto tuner motor Updated maximum travel range will be displayed to the right of the bu...

Page 39: ...f the orifice for the slow pumping the system will shut off the power to the valve controller after 600ms Once the sample chamber has been pumped to below 1Torr the system will turn on the power to th...

Page 40: ...because it may cause dust particles to get into the bottom surface of the o ring groove If the PFPE vacuum grease has been wiped clean it may also increase the gas leak rate Please purchase the Apiez...

Page 41: ...a intensity is usually relative lower at this impedance matching position 3 Increase the rf power or pulse duty ratio Plasma may fail to ignite if the rf power or pulse duty ratio is too low 4 For imm...

Page 42: ...nute Power up the system again 3 Set MFC server speed to 5 or less in system screen 10 8 How to check the leak rate on the gas delivery system Step 1 Set gas flow rate to zero on all input ports Pump...

Page 43: ...ix oxygen with some argon or nitrogen 10 11 Why sample chamber may be bright when remote plasma source is activated For some process gases such as oxygen the excitation decay time may be quite long It...

Page 44: ...serious effect If high purity argon or hydrogen gas is required to reduce the oxidation of the samples such as silver or copper samples then it is recommended to pump out of the contaminated gas in th...

Page 45: ...cted to the plasma cleaner 3 Disable the pressure sensor manually pump down the chamber by turning on the vacuum pump and open the pumping valve Wait for 2 minutes Then run a high power cleaning recip...

Page 46: ...nt that may need to be serviced regularly by the users And it is not covered by the normal two years of warranty To replace the pressure sensor first take out the top two screws on the back panel of t...

Reviews: