sp3 HFCVD Diamond Deposition Reactor
Contents
1. 1 0 2 0 3 0 4 0 Marvell Nanofabrication Laboratory University of California Berkeley Lab Manual Chapter 6 25 Sp3 Model 655 Series HFCVD Diamond Deposition Reactor Sp3 595 Equipment Purpose 1 1 The Sp3 model 655 series hot filament CVD HFCVD diamond deposition reactor produces thin film polycrystalline diamond coatings on 4 and 6 Si wafers The hot filament technology allows deposition of high quality nano crystalline NCD and microcrystalline MCD poly diamond films with controllable grain size uniformly over large areas and multiple wafers Manual Scope 2 1 This manual describes the operational procedures and user level trouble shooting guides of the Sp3 HFCVD diamond deposition reactor system Please refer to the vendor equipment manual hard copy in the Nanolab office for facilities requirements and maintenance issues Applicable Documents 3 1 4 1 Sp3 Hot Filament Diamond Deposition Reactor User Manual Sp3 document 3 2 4 2 Sp3 Hot Filament Diamond Deposition Reactor Service Manual Sp3 document 3 3 4 3 Material Safety Data Sheets for the following materials H2 CH3 No TMB Definitions amp Process Terminology 4 1 HFCVD Hot filament CVD the technique that uses an array of W filament wires that gets carburized in a heated methane environment to form a resistive heating element to provide energy required for the diamond deposition reaction uniformly over a large area 4 2 MCD Micro cr2. 6 4 7 7 Substrate temperature heavily affects the growth rate grain size and film quality For MCD films the optimum deposition temperature is between 700 C 720 C and is set to be 720 C for the current tool setup The substrate temperature is sensed by a thermocouple that contacts the wafer from the backside The temperature is primarily a function of the filament temperature the distance between the wafer and the filament and thermal conductivity of the cooling stack under the wafers Gas flow rates and process pressure also plays a role in determining the substrate temperature Filament temperature The heater filament operates at 1950 C and its temperature is monitored by a fixed position 2 color pyrometer The W wires that form the heating filament turn into tungsten carbide as the heater temperature is ramped up in the methane atmosphere and exhibits a very nonlinear l V curve The resistivity and thus the heat radiation characteristics of the filament depends heavily on this carburization process and other minor details such as the type and vendor of the W wire used For process stability and repeatability purposes the filament carburization steps and temperature adheres to the OEM developed recipe and is fixed Cooling stack amp wafer filament distance The temperature control in the tool is open loop It is primarily controlled by the thermal conductivity of the cooling stack under the wafers that transfers the heat away
3. 7 8 f 1 1 0 1 ra ny Lm 2 se Eg X e ue I T g e 3 x N NN NN NNN 8 Temrnrad VIGEN Fig 13 Recipe editor page UCE Marvell Nanolab ses Filament Threading Assembly Notes Fig 14 Filament Threader video sp3 Chapter 6 25 11 0 Appendix A Seeding solution prep guidelines done once year 11 1 3000mi Methanol mixed with 45ml diamond seeding solution for today s setup in a 3500 ml beaker 11 1 1 The solution is sold in 15ml vials with a 6 month shelf life Part 48750101 11 2 After mixing a fresh solution and prior to each wafer seeding run one should place the solution without any wafers in the ultrasonic bath for 10 minutes 11 3 The solution should be kept at room temperature both for storage and during seeding 11 4 The solution temperature rises due to ultrasonic agitation during seeding Therefore if you are successively seeding more than one wafer then place ice cubes in the ultrasonic bath water and supply more ice as it melts Marvell Nanofabrication Laboratory University of Califomia Berkeley NanoLab Qualification Form Sp3 Model 655 Series HFCVD Diamond Deposition Reactor Sp3 595 Name Office Date Campus Phone Home Phone Login Trainer Equipment Qualification Test Passed Initial Oral Qualification Checklist O Superuser Login Name Date Superuser Signature
4. filament current and voltage than the following Deposit 2 step because the tool is still in the process of carburizing the W filaments The carburization process reaches steady state at the end of the 90 min time period of this step The only parameter that will be of interest to the users and also the only parameter they are allowed to change is the TMB flow rate as set by _oH2 TMB as marked in Fig 13 This parameter sets the dopant gas concentration and can be set to zero if the user wants an undoped film The current setting of 1sccm is found to give reasonable conductivity and low acoustic damping loss for MEMS resonators Users can experiment and adjust this parameter according to their process needs Deposit 2 Step This step uses a higher filament voltage and current value and forms the main part of the deposition process There are two parameters that the users are allowed to change at this step JoH2 TMB Sets the dopant gas flow rate and should be set to the same value as in step Deposit 1 yotep Time This is the setting that should be used to control film thickness For example the standard UCB1T35H recipe provided by the vendor gives a 2um MCD film in 35 hours If the one would like to deposit 1um then the required time is 17 5 hours Since users are advised not to change the duration of Deposit 1 the step time of Deposit 2 should be set to 17 5 1 5 16 hours i e 16 00 00 in the text box The standar
5. tray accumulates diamond and starts to generate flakes of varying size if it is not regularly cleaned These particles will fall onto your wafers especially when the tray goes under excessive stress due to expansion at high temperature and spits out the accumulated diamond flakes Report this condition to staff if you notice a dirty tray and they will provide a clean tray if there is not one already in the wafer tray cabinet and clean the dirty ones 9 5 There are finger prints and other marks on the wafer tray 9 5 1 Always touch the reactor parts and the tray with clean gloves Any residual organics on the gloves will lead to marks on the parts during diamond deposition sp3 10 0 Fiqures amp Schematics Fig 1 Diamond seeding setup Chapter 6 25 Methanol Level Tank DI Level d Fig 2 Liquid levels for methanol and DI pr Fig 4 Wafer placed in seeding bath Fig 5 Spinner dry after seeding bath Fig 6 Filament maker fixture sp3 Chapter 6 25 Fig 10 Properly completed reactor setup ready for Fig 9 Wafer i ig 9 Wafer loading closing the lid and run the process HRR Pe diamond y F d KET tarhnAl une LOGIN lologlies Fig 11 GUI Page Fig 12 Desktop page sp3 Chapter 6 25 Step duration Recipe name Step Name I Jiposit 1 F rot Table Step Tine fi Thveshol 00 Deta fo oo Step Type Normal v Data Rate f 300 Secs 4 1 7 GE 3 14 745 J6
6. cipe deposits 2um MCD diamond with deposition time set to 35 hours deposition rate 9 5A min temperature at 720 C and 1sccm TMB flow that gives 10kQ square sheet resistance MCD_Var Variable MCD deposition recipe that is an exact replica of UCB1T35H Users are allowed to change the deposition time for controlling film thickness and TMB flow rate for controlling conductivity Users are allowed to use only the recipes in the User Recipes folder and only modify the variable recipes designated with the suffix Var in the recipe name Users should never modify the standard recipes in the User Recipes folder These recipes are provided by the equipment manufacturer and are proven to work and produce high quality diamond films They should be used as a template to modify the variable recipe as needed primarily to change deposition time for thickness control and doping level Users should never attempt to change the OEM provided service recipes in folders other than the User Recipes folder 8 0 Equipment Operation 8 1 Diamond deposition process consists of the following steps 8 1 1 8 1 2 8 1 3 8 1 4 8 1 5 8 1 6 8 1 7 8 1 8 8 1 9 Wafer cleaning Wafer seeding Filament making Filament loading Wafer loading Filament holder loading Recipe setup Recipe running Unloading filament holder 8 1 10 Unloading wafers 8 1 11 Clean up amp Log out sp3 Chapter 6 25 8 2 Wafer cleaning 8 2 1 8 2 2 8 2 3 S
7. d recipes should cater to the majority of the users needs However if your process requires different deposition conditions then discuss them with the process staff and potentially the tool vendor to clear the feasibility and safety concerns Once recipe setup is complete click Verify and make sure the software does not prompt any warnings after verification process Save your recipe under the File gt Save Recipe menu Click File gt Download Recipe to download the adjusted and verified recipe to the reactor The software will prompt a confirmation message click OK Click Done which will bring you back to the Desktop page 8 9 Run Recipe In the Desktop page select Control gt use GUI to arrive at the graphical user interface that will allow you run the recipe you loaded in the previous section sp3 8 9 2 8 9 3 8 9 4 8 9 5 8 9 6 8 9 7 Chapter 6 25 Check that the recipe name under the Current Recipe display matches the recipe you loaded to the reactor in section 9 7 Click Start The software will prompt a popup menu Click Start again on this menu Click OK to the confirmation message The reactor status should now change to RUN You can monitor the current step remaining step time and total remaining time information from the header display at the GUI page 8 10 Unloading Filament Holder 8 10 1 8 10 2 8 10 3 8 10 4 8 10 5 8 10 6 8 10 7 8 10 8 The machine should be
8. e a mess behind Never run the reactor with the holder assembly still attached to the filament array WARNING If there are any filaments that hang too loose and close to the wafers please do not proceed until you replace the faulty filament Loose or bent filaments will lead to small current flow and lower temperatures If the filament touches the tray and or the wafers it will melt over the tray and the wafer Your wafer will crack and the quartz tray will be damaged The filament wire can cause an arc and can damage the chamber walls The complete run may abort as well If the filament does not touch the wafers yet is loose and closer to the wafers then the rest of the filaments you will have thickness non uniformity over that area Check and verify there are no faulty filaments and you can now close the reactor lid and it is ready to run 8 8 Recipe Setup 8 8 1 8 8 2 8 8 3 8 8 4 8 8 5 8 8 6 8 8 7 8 8 8 8 8 9 Click LOGIN Enter your 4 digit user ID given to you upon qualification when prompted by the tool and click Enter Note Sharing user IDs with other lab members is prohibited You now have access to the GUI page that has main controls to run the tool as shown in Fig 11 Click Menu then Desktop Click Recipe menu in the Desktop page as shown in Fig 12 The software will prompt you for the recipe folder Users are only allowed to use the User Recipes folder Select the recipe you would li
9. e seeding bath Take the aluminum foil lid with the Parafilm lining under it off the beaker Place a wafer on the carrier handle as in Fig 3 It is recommended to have a mouth cover or face shield on all the time during the wafer seeding process in order not to breathe over the wafers and to protect both the seeded wafers and the seeding solution Place the carrier handle in the seeding bath as in Fig 4 Run the ultrasonic bath for 5 minutes with the wafer in the solution It is possible to under seed the wafers if you run the ultrasonic bath for less than 5 minutes But after 5 minutes the wafer surface saturates so over seeding is not a concern Place the wafer onto the spinner located to the left of Msink20 as shown in Fig 5 Run spinner process G set to 500 rom for 10 seconds followed by 1500 rom for two minutes Wet the wafer with Methanol during the first 15 seconds of the spinner run from a squirt bottle as it spins Unload the wafer from spinner Store securely to avoid contamination before loading to the diamond reactor Repeat until all the wafers are seeded Turn the ultrasonic shaker off Place the aluminum foil cap with the Parafilm lining under it back Tightly seal the edges of the beaker to minimize evaporation Replace the Parafilm layer and aluminum foil if it is torn up Disable the seeding setup 8 4 Filament Making 8 4 1 8 4 2 8 4 3 8 4 4 8 4 5 There are two possible fixtures to strin
10. from the wafers and also sets the distance between the wafers and the heating filament as given by the difference between the fixed distance between the filament wires and the base of the deposition chambers and total height of the cooling stack materials The cooling stack consists of a group of machined plates of varying thickness made of different materials such as graphite aluminum copper It also uses quartz washers and spacers to create air gaps to induce higher thermal resistivity than a solid would where needed in the stack yet the gap s thermal resistivity is a function of process pressure and gas flow rate This variation of material types and thicknesses allow variation of the substrate temperature however it is achieved in discrete steps rather than in a continuous fashion due to the limited number of cooling plate combinations 720 C is set to be the optimum tool operating temperature The fabrication of a set of cooling plates with finer thickness steps that will allow finer control of temperature is in progress and will be characterized and installed by process staff The current cooling stack should never be tampered with and any processes that require a different deposition temperature should be discussed with process staff sp3 Chapter 6 25 5 0 Safety 5 1 High Temperature 5 1 1 The chamber lid cooling stack heating filament and its holder gets very hot during deposition and should be handled only after they cool down t
11. g 8 5 1 8 5 2 8 5 3 8 5 4 8 5 5 8 5 6 8 5 7 Fasten the H shaped holding fixture to the filament holder assembly with the four 3 8 nuts if it is not already in place as shown in Fig 7 Loosen the nuts holding the filament array assembly together with the 3 8 and place them in the provided plastic box Remove the top halves of the filament array assembly Shake out and clean any used out filament ends from previous runs Wipe away any remaining diamond residue Insert and evenly space all 31 filaments into the array assembly Replace the top halves of the filament array assembly making certain the filaments are firmly seated Replace any filaments that are too long too short or damaged Tighten the nuts for the filament array assembly Do not over tighten nuts as they will crack due to thermal expansion at the elevated process temperature 8 6 Wafer Loading 8 6 1 8 6 2 8 6 3 8 6 4 Enable Sp3 Open the reactor lid The reactor should look clean as in Fig 8 free of diamond flakes broken filaments etc that may remain from previous runs Vacuum clean any particles and flakes Place the proper quartz wafer holder for 6 or 4 wafers located in the shelf next to the tool Align the four holes drilled on the wafer holder to the four quartz spokes that go through the cooling stack as shown in Fig 9 Be careful in order not to crack the quartz tray or spokes as they can get brittle over time due to d
12. g the filaments Section 8 4 2 8 4 8 describes the method using the filament maker fixture and the method using the filament threader is explained in the video which can be accessed by clicking on the icon in Figure 14 Use of the filament maker fixture to facilitate this process is shown in Fig 6 Bend loose end of wire from the spool over the metal fixture end to form a 90 bend at about 10mm from the tip of the wire Insert bent tip as it will be inserted in the filament array assembly into the outer hole in the filament maker bar Pull the filament wire tightly along the length of the filament maker bar to the end of the bar Make sure there are no bent spots and kink along the wire since such spots will sp3 8 4 6 8 4 7 8 4 8 Chapter 6 25 create high resistivity points and break the wire at high temperature and ruin your process Bend the uncut end to a 90 angle over the bar Cut the bent end at about 10mm from the bend Place the finished filament in a finished tray to prevent damage and to minimize tangling There are three empty trays provided for this purpose kept under the filament processing table next to Sp3 Do not place more than fifteen wires in one tray as more wires will likely get tangled and ruined Repeat steps 9 3 1 through 9 3 5 for the minimum of 31 filaments required to fill the filament holder as well as a few extras to replace any long short or damaged filaments 8 5 Filament Loadin
13. iamond accumulation Place wafers into the opening of the quartz wafer holder placing all open positions with either process wafers or dummies 8 7 Filament Holder Loading 8 7 1 8 7 2 Flip the filament array assembly already prepared as described in section 9 5 around to face the wires down holding it from the H shaped holding fixture Align the two holes drilled at the edges of the filament array assembly to the two quartz supports in the CVD reactor Slowly lower the filament array assembly as guided by the supports through the holes as shown in Fig 10 Be careful as the quartz supports are fragile sp3 8 7 3 8 7 4 8 7 5 8 7 6 8 7 7 8 7 8 8 7 9 8 7 10 8 7 11 Chapter 6 25 While holding the filament array with one hand use your free hand to adjust and align the filament tensioner at the far end of the reactor to the smaller holes on the other side of the filament holder assembly as shown in Fig 10 Place the copper strap over the bolt on the one side Place and tighten the 5 8 nuts Note Two washers go on the side of the filament holder with the copper straps placed under and over it and only one washer on the side with the tensioner fixture Remove the H shaped holder assembly fixture This is a step that you can easily forget by mistake and the results can be disastrous The holder assembly is made of aluminum and will short the current through the heating filaments and will melt to leav
14. idelines 9 1 Process aborts with Jow N gt alarm 9 1 1 There is no N to the tool because it s not enabled or there is an issue with the house N2 supply Make sure the tool is enabled and there are no general N supply problems sp3 Chapter 6 25 9 2 Wafer temperature is not between the 700 C 720 C band 9 2 1 9 2 2 9 2 3 The most likely cause is a few broken filaments due to bad filament making The tool will keep running even if up to three filaments break Your run will complete but at a lower temperature and thus at a lower deposition rate You will observe thickness non uniformity under the broken filament areas You can check the filament and wafer condition from the viewing port located at the front right side of the reactor where you can see if any filaments are broken or not Caution Always keep the lid of the viewing port closed when the reactor is running Looking into the reactor as it runs without the filter on the lid of the viewing may hurt your eyes Temperature inconsistencies can be also due to hindered thermal conductivity between the backside of the wafer and the cooling stack due to excessive diamond accumulation over the cooling stack over time Contact equipment staff for proper tool cleaning 9 3 Run aborted before completion 9 3 1 More than three filament wires broke during deposition 9 4 Particles or shiny spots on random points across the diamond film 9 4 1 The quartz wafer
15. iewed before being cleared to be used in the diamond seeding bath Wafer seeding process flow 8 3 4 1 Enable the ultrasonic bath shown in Fig 1 from Mercury 8 3 4 2 Enter the number of wafers you will seed and their diameter in the comments section e g 2x6 1x4 8 3 4 3 Keeping an accurate count of cumulative number of the wafers processes in the bath is very important because the solution is good for a total of 200 6 wafers or 500 4 wafers and needs to be replaced once this count is reached 8 3 4 4 Check the water level in the ultrasonic bath tank The water outside the beaker in the ultrasonic bath tank constantly evaporates therefore add water to the ultrasonic bath tank until the level meets the 1500mL mark line of the graduated beaker that houses the diamond seeding bath as shown in Fig 2 8 3 4 5 Note Take care to never add or spill water into the diamond seeding solution in the beaker during this process as it will ruin the solution sp3 8 3 4 6 8 3 4 7 8 3 4 8 8 3 4 9 8 3 4 10 8 3 4 11 8 3 4 12 8 3 4 13 8 3 4 14 8 3 4 15 8 3 4 16 8 3 4 17 8 3 4 18 8 3 4 19 8 3 4 20 8 3 4 21 Chapter 6 25 Check the methanol level in the diamond seeding solution beaker which should read 3000m L If the level is lower than 3000mL due to evaporation then add more methanol to fill it up to 3000mL but not more as shown in Fig 2 Run the ultrasonic bath for 10 minutes with no wafers in th
16. in IDLE state and the Current Step should display O Standby once your run is successfully complete Wait until the temperature reading of the thermocouple that monitors substrate temperature reaches 30 C as displayed by the reading Right as shown in Fig 11 Open the reactor lid Fasten the H shaped holding fixture to the filament holder assembly with the four 3 8 nuts Loosen the three 5 8 nuts two on the side with copper strap and one on the tensioner side with the wrench Pull off the copper strap from the filament holder assembly Remove the entire filament holder assembly by slowly lifting it up by holding it from the H shaped fixture Be careful not to exert lateral pressure on the quartz support rods Furthermore the carburized filaments are very fragile and will crumble over your wafers if you shake the fixture too much as you lift it up Take the filament holder over a trash can and clean the used filaments away which should break apart easily and place it back over the filament preparation table 8 11 Unloading Wafers 8 11 1 8 11 2 Take the quartz wafer holder tray out slowly without cracking the tray or the quartz supports Take the wafers out with a tweezer 8 12 Clean up amp Log out 8 12 1 8 12 2 8 12 3 8 12 4 Vacuum clean any diamond flakes broken filament residue etc in the reactor Close the reactor lid Log out from the tool Disable Sp3 9 0 Troubleshooting Gu
17. ink8 piranha cleaning for wafers without any metal on them svc 14 cleaning in msink1 for wafers with metal on them Wafers must be properly cleaned before seeding them with diamond nanoparticles This will ensure proper seeding and high quality film growth on your samples as well as prevent accumulating contaminants in the seeding bath that will compromise everyone else s processes 8 3 Wafer seeding 8 3 1 8 3 2 8 3 3 8 3 4 Proper seeding of wafers is a critical part of the diamond coating process and any errors in this step will affect all the later steps The diamond seeding setup is located at Msink20 in the Nanolab Material Restrictions 8 3 3 1 The following materials are strictly not allowed in the diamond seeding bath and will ruin the seeding solution 8 3 3 2 Water pay attention to not to drop any water into the solution Wafers must be dry as well 8 3 3 3 Graphite completely ruins the solution 8 3 3 4 SiC results the solution to take a dark color For SiC substrates a dedicated bath is needed SiC should not be allowed in the general use bath 8 3 3 5 Plastics contaminates the solution As such the solution cannot be stored in a plastic bottle it should be kept in glass beakers for seeding use and long term storage 8 3 3 6 Diamond coated wafers sp3 vendor had concerns on seeding already diamond coated wafers It can possibly degrade the seeding solution Any carbon rich film should be rev
18. ke to modify e g MCD var for changing the deposition time doping level etc Note Users are only allowed to change the variable recipes marked with the suffix Var in the file names This prevents accidental changing of the standard baseline recipes which users can use as a template to adjust the variable recipes for their needs Selecting the recipe and clicking Open will bring you to the recipe editing page as shown in Fig 13 There are various steps in a recipe file however only two of these steps are directly relevant to the film deposition as will be discussed below The remaining steps sp3 8 8 10 8 8 11 8 8 12 8 8 13 8 8 14 8 8 15 8 8 16 8 8 17 8 8 18 8 8 19 8 8 20 8 8 21 8 8 22 8 9 1 Chapter 6 25 perform auxiliary functions such as leak checking temperature stabilization chamber back filling etc The only two steps that the users need to change to control deposition parameters are step numbers 13 and 14 which are the Deposit 1 and Deposit 2 steps respectively as shown in Fig 13 Changing any other step will not be relevant to the film deposition and will only compromise the process by messing up the vendor specified parameters for basic functions such as leak checking and other process safety aspects and therefore is prohibited Deposit 1 Step Users are advised not to change the duration of this step which is set to 01 30 45 in hr min sec format This step uses a different
19. o room temperature 5 2 High Voltage 5 2 1 This tool uses high voltage electrical power in various subsystems such as the filament power supply User should never open the power supply enclosures and panels located around the tool 5 3 Emergency Stop Button 5 3 1 The emergency off EMO push button switch is located on the main control panel next to the user interface screen in the event that the reactor must be powered down quickly and should only be used for emergency situations This switch will disconnect all primary power to the reactor in the system AC distribution cabinet It will interrupt any process that is in operation at the time it is pushed To reactivate the system the EMO switch must be pulled forward before restoring system power which should be done by the equipment staff 6 0 Process Data 6 1 7 0 Available Processes Gases Process Notes 7 1 Sp3 accepts four 6 or nine 4 Si wafers with quartz wafer holders available for both wafer sizes There cannot be empty slots in the wafer holder during deposition because the empty areas would expose the graphite surface of the wafer cooling stack that would react with process gases and damage it Therefore all wafer slots must be filled with either process or dummy wafers 7 2 Only the following materials are allowed in the tool without asking for explicit process review by process staff 7 2 1 Films grown or deposited in the Nanolab furnaces Si SiGe SiO SigN
20. or silicon rich nitride poly Si AIN 7 3 Following materials are strictly forbidden in the tool 7 4 Any exposed Nickel Platinum Cobalt Iron are strictly off limits These metals are catalysts for CNT growth and will not only ruin your process but also severely contaminate the chamber 7 4 1 No Gold and other highly diffusive metals such as Cu Ag since the wafers processed in Sp3 should be able to be further processed in non MOS clean furnaces 7 4 2 Photoresist will burn and contaminate the chamber and is not allowed 7 5 Wafers that have metals anywhere in the process stack should be discussed with process Staff first before getting processed in Sp3 7 5 1 Buried Ni Pt Co and Fe films that are completely covered under another layer e g oxide can be considered for processing in Sp3 after process review and approval by process Staff sp3 7 5 2 7 5 3 Chapter 6 25 The MFC s used in SP3 have the following values N gt 10 000 sccm H 5 000 sccm CH 200 sccm TMB Lo 25 sccm calibrated as Hz TMB Hi 50 sccm calibrated as H The TMB concentration is 2 1 balance Hb Other metal films such as Ti W TiW will probably carburize during deposition yet may not contaminate the chamber Their presence should also be discussed with process Staff 7 6 Available Recipes 7 6 1 7 6 2 7 6 3 7 6 4 7 6 5 UCB1T35H Standard MCD deposition recipe provided by the equipment manufacturer This re
21. ystalline diamond with 1um grain size 4 3 NCD Nano crystalline diamond with 0 1um grain size 4 4 Typical Source Materials 4 4 1 TMB Trimethylboron B CH3 3 is used for in situ doping of diamond films 4 4 2 CH Methane carbon source for diamond deposition 4 4 3 H Dissociates into atomic H at high temperature and plays an important role in maintaining the desired diamond tetrahedral sp3 configuration that gives high quality diamond over the undesired sp2 configuration which is simply graphite 4 5 Substrate Material 4 5 1 Sp3 is configured to deposit poly diamond simultaneously over four 6 or nine 4 wafers with two types of trays available for each wafer size Standard Si wafers supplied by the Nanolab or other vendors can be processed in the tool with further material stack restrictions explained in sections 8 1 and 9 2 1 sp3 Chapter 6 25 4 6 Available Film Types 4 6 1 The tool is capable of depositing both MCD and NCD films however only the MCD film type has been repeatedly deposited and well characterized as of now Therefore the current recipe available to users is for depositing MCD films Characterization of MCD films took precedence because they are known to give lower damping loss for MEMS resonators Characterization of the NCD process is in progress and will be released once process staff tests the NCD recipe given by the OEM 4 7 Temperature Control 4 7 1 4 7 2 4 7 3 4 7 4 4 7 5 4 7
Download Pdf Manuals
Related Search