Measurements

Materials Characterization

Atomic Force Microscopy (AFM)

CNSI has a room devoted to AFM including 2 models Asylum and NanoScope. Contact Mark Cornish <cornish@engineering.ucsb.edu> to get tips and register. The cleanroom also has a NanoScope AFM managed by Bill Mitchel <mitchell@ece.ucsb.edu>.

Asylum AFM

Media:Asylum_AFM_MFC-3D_Procedure_v2.docx

Media:Asylum_AFM_MFC-3D_Procedure_v1_-_Basic_Tapping_Mode.docx

NanoScope AFM

Bill will approve you to sign-up once someone he trusts trains you.

Analysis

Igor Pro demo: http://www.wavemetrics.com/support/demos.htm Asylum download requires a login, and to get one takes a little while. Is it possible to upload that to the wiki? Gwyddion and GTK+: http://gwyddion.net/download.php#stable-osx it recommends a specific GTK+, not sure why it matters though. If you have it from Pidgin or something I'm sure it'll work.

Focused Ion Beam

Mainly used to create/image cross sections and perform TEM lamina preparations.

[MRL Micrscopy]

Cross Sections

Needs gold coating or conducting surface.

Will mill out a trench with ion beam and image the cross section at a 52 ° tilt. Can get up to 100kX SEM images and normally create trenches up to 20μm

Best when you don't want to destroy your samples and/or your tolerance to cleaving is less than 25 µm, otherwise try cleaving

Contact Daryl Spencer to setup a session, two weeks notice is usually sufficient.

X-Ray Diffraction (XRD)

XRD qualification of wafer:

This is one scan in ~20minutes if you know the offcut and direction already.

1. Note offcut amount and direction. Draw arrow relative to wafer flats. ([110] is the direction perpendicular to the major flat)
2. ID the layer peak(s), if separated from the substrate peak, and give the strain(s) (or just peak separation)
3. ID superlattice/QW fringes. Count them (e.g. -2 to +3) and note spacing in arcseconds
4. Make note of any other strong fringe peaks or broad/mysterious layer peaks

NB: Offcut on GaAs may be up to 10degrees. (XRD person try a pole search to locate). InP offcut ~0.2degrees is standard and often not noticed during XRD.

External FIB/TEM

On Thu, Aug 14, 2014 at 3:44 PM, Demis John <demis@praevium.com> wrote:

   FYI, here is the contact for the local TEM consultant, John Redding, who routinely does both FIB & TEM:
   John Redding <johndredding@earthlink.net>
   If you need a quick TEM done and getting trained isn't worth it, I'd suggest doing this so that you can just sit with him while he FIB's & TEM's so you can direct him to the features of interest (or just tell him if that works).
   There is huge benefit to sitting next to someone while they TEM your sample, especially if you're not exactly sure what you are looking for.
   -- Demis

Optical Characterization

LI curves

"Example:" This technique allows you to measure output power vs. injection current. The follwoing equipment is used:

• Keithley (link to equipment)
• Agilent powermeter (link)

The measurement can be controlled using this (link) software. A sample plot looks like this: (insert picture). More about this technique can be found in:

1. Mr.X et al., IEEE Journ. of Lightwave Technol., vol. x, pp. xxx-xxx, Aug. 2005
2. Our own uploaded description (in doc format maybe)

Electrical characterization

Analysis: http://gwyddion.net/download.php#stable-osx

Microwave measurements

Linearity measurements (OIP2, OIP3, SFDR,...)