From jwc at snf.stanford.edu Fri Aug 8 14:30:41 2008 From: jwc at snf.stanford.edu (James Conway) Date: Fri, 08 Aug 2008 14:30:41 -0700 Subject: Comment sem4160 SNF 2008-08-08 03:41:08: noisy? Message-ID: <489CBB01.7040507@snf.stanford.edu> Hi Debbie, If you are free I am going to be working on the S4160 after ~3:30 PM today. I would like to review with you the column set up and make sure you obtain the brightness you need to obtain your image or measurements. Likely you came onto the system when it was set up for imaging very tiny structures using the smallest apertures and encountered less beam current than you are accustomed to. If you are not here or available this afternoon please stop by Monday afternoon when I will likely also be working on the tool with the Hitachi Field service experts whom are here doing repairs to EBEAM. Thank you, James Conway dgunning at snf.stanford.edu wrote: > Image is extremely noisy and has been like this for a couple of days. I, and other users, haven't been able to get decent images.. > > -------------- next part -------------- An HTML attachment was scrubbed... URL: From jwc at snf.stanford.edu Fri Aug 8 17:24:01 2008 From: jwc at snf.stanford.edu (James Conway) Date: Fri, 08 Aug 2008 17:24:01 -0700 Subject: sem4160 problem In-Reply-To: <2745.171.66.130.247.1218234282.squirrel@www.physics.gla.ac.uk> References: <487E9B88.8000906@snf.stanford.edu> <2590.171.66.130.247.1218225138.squirrel@www.physics.gla.ac.uk> <489CBB64.20507@snf.stanford.edu> <2745.171.66.130.247.1218234282.squirrel@www.physics.gla.ac.uk> Message-ID: <489CE3A1.7030303@snf.stanford.edu> Hello sem4160 Users: Often it is best to ignore reports from new Users until they come up to speed on the system... Like riding bicycles and playing sports, it all get easier and better when you train and practice your skills. I checked out the system today and found no specific issues regarding resolution or brightness of the images. Suspect that Ted Berg or another expert operator may have realigned the column when they used the tool since your last session. We set up the column and imaged in a number of SEM modes and acceleration voltages and after careful column gun alignment and aperture adjustments we had suitable brightness in all aperture strip positions. Couple points to check if you run into problems: Best take off angle to the SE detector is between 10 and 18 mm Working distance WD. Adding a little tilt on the stage can greatly increase brightness too. Be sure to reduce contrast if you are observing high signal to noise in the image and then increase brightness. In normal practice on initial view in SE SEM mode I bring up contrast until I just start to see the noise speckles in the image, (i.e., dark Current of amplifier aka shot noise) then reduce Contrast just slightly till the screen is no longer noisy, then bring up brightness to the CRT. If you still do not have a sufficient signal then open to the next larger hole (smaller number) in the movable aperture strip. Normal mode is aperture No 3. Finally if you do not have enough brightness in TV view mode employ the slow scanning functions and you will have a much better image concurrent with the longer dwell times per pixel. Lastly you can change the condenser lens setting from 12 to 10 or 8 even -- but with the caveat that ultimate resolution will suffer greatly. At the end of my session today I set up the column for 10 keV 10 mm WD. using aperture strip no 3. This should be fine for all but the highest resolution users working above 200kX. Please give us some feedback from your sessions over the weekend by making a comment or if you are suffering and need assistance report a problem on coral for the tool. Next week we will continue to evaluate performance on the tool seeking solutions if we can trace to a specific problem. Thank you for your interest in Ebeam Technologies here at SNF. Have a Nice Weekend, James Conway d.gunning at physics.gla.ac.uk wrote: > Hi James, > > I'm not available this afternoon. I heard reports from another user > saying they had the same problem...so I don't think it was necessarily > just the way I had set it up. I'll try using it again over the weekend > and then maybe I'll come along on Monday if I have time. Thanks for a > quick reply! :o) > Regards, > > Debbie > > >> I will be in the lab after ~3:15 - 3:30 and please join me for our >> session with trishna sengupta. >> >> I will do my best to get it all set up for you! >> >> All the very best, >> >> James Conway >> >> d.gunning at physics.gla.ac.uk wrote: >> >>> Hi James, >>> I left a comment on coral about noise on the sem4160 - I wonder if >>> anything is being done about it? I really can't get a good image..and >>> I need to use it a lot over the weekend. >>> Regards, >>> >>> Debbie >>> >>> >>> >>> > > > > -------------- next part -------------- An HTML attachment was scrubbed... URL: From jwc at snf.stanford.edu Thu Aug 21 14:50:43 2008 From: jwc at snf.stanford.edu (James Conway) Date: Thu, 21 Aug 2008 14:50:43 -0700 Subject: All Users are requested to not adjust the upper movable apertures on these columns. Message-ID: <48ADE333.1010308@snf.stanford.edu> Greetings /semhitachi /and /sem4160 /Users: *Users are requested to not translate the upper movable aperture on either of the SEM columns.* This is called the Beam Monitor Control aperture and its function is to monitor the beam current at that aperture during SEM operations on the tools. Often Users will see the BMC button flashing as emission of the FE-Tip falls below a specific set point (~ -20% delta Emission Current). You can bring the emission back up to the 10 ?A set point simply by pressing the 'HV ON' button again without shutting the beam down. The lower movable aperture strip called the Beam Alignment Aperture, it can be translated by any User to align the Beam to the center of the aperture resulting in no image shift as you change working distance (focus). If you are unsure, confused, or just need help, please see James Conway during any training session on these tools, or visit me during my office hour. Tuesday - Friday 8:30 - 9:30 AM daily. Thank you for your interest in Ebeam technologies here at SNF! James Conway -------------- next part -------------- An HTML attachment was scrubbed... URL: