Lab and Coral NameICL / AFM
ModelVeeco D3100
SpecialistEric Lim    (Kurt Broderick)
Physical Location2F 2-North Etch
Process CategoryMetrology
Material KeywordsNone
Sample Size6" Wafers, 4" Wafers, Pieces
AlternativeICL / P10, ICL / SEM
Keywordssingle wafer, manual load, top side of sample, manual operation, alignment
The Atomic Force Microscope (AFM) is a very high resolution Scanning Probe Microscope for imaging surface topology. It uses a sharp tip of the order of nanometers to scan the surface of the sample and produce a map of the surface topology.

Best forimaging nanometer scale patterns, characterizing sourface roughness; imaging photoresist without running into charging effects like in the case of the SEM
LimitationsLarge step heights; Imaging wide areas can be very time consuming; Cannot reproduce sidewall angle and roughness.
Characteristics/FOMThis AFM typically operates in tapping mode, in which the cantiliever supporting the sharp tip is driven at its resonance frequency. Interactions between the tip and sample cause the amplitude of vibrations to change. These amplitude modulations can be accurately measured, resulting in a map of the surface topology. Compared to contact mode, this regime has the benefit of reduced damage to the sample.
Caution withUse lower scan speeds for large step heights to avoid breaking the tip.
Machine Charges (academic rate)9pu/hour
Process Matrix Details

Been in the ALDSamples that have been in any of the ALD systems
Pyrex SubstratesPyrex substrates can be a concern due to high sodium content, which contaminates CMOS frontend tools
III-V SubstratesAny III-V substrates, e.g. GaAs, GaN, InP, and so on. Note though that many common III-V substrates will also carry the Au flag, but there are some GREEN III-V substrates.
Germanium on surfaceSamples with germanium on the surface (typically grown films)
Germanium buriedSamples with germanium buried below a different film
PiecesWafer pieces may not be handled by the equipment, and are harder to thoroughly clean - preventing them from running in certain tools.
Gold or RED color codeRED color code substrates. These are gold-contaminated or have been processed in gold contaminated tools. Gold and other metals can contaminate silicon devices (GREEN color code) and have to be separated.
Any exposure to CMOS metalIf the sample had ever seen a CMOS metal (or a tool that accepts CMOS metal), then some frontend tools could be contaminated by this.
CMOS metal on surfaceCMOS compatible metals exposed on the surface. These are Al,Ni,Pt,Ti,TiN. Other metals such as Au are *NOT* part of this.
CMOS metal buriedCMOS compatible metals covered entirely by a different material. These are Al,Ni,Pt,Ti,TiN. Other metals such as Au are *NOT* part of this.
Been in the STS DRIEThe DRIE etch leaves behind polymer residues on the sidewall ripples, which can be a contamination concern for some tools.
Been in the SEMA sample viewed in the SEM must have used the appropriate chuck to avoid cross-contamination
Been in the Concept1The Concep1 deposits dielectrics on GREEN wafers, however it also accepts metal and there can be cross-contamination for diffusion area
Has PhotoresistSamples with photoresist cannot be exposed to high temperatures, which is typical in deposition tools. Outgassing can be a concern.
Has PolyimidePolyimide is a very chemically resistant polymer, and can tolerate higher temperatures but cannot be exposed to typical PECVD deposition temperatures or diffusion furnaces. Outgassing can be a concern.
Has Cured SU8Not fully cured SU8 residues can heavily contaminated plasma chambers or destroy other user's samples, but fully cured SU8 is permitted in certain tools.
Coming from KOHAfter a KOH etch, the samples must receive a special clean because the K ions are highly contaminating to CMOS frontend tools
Coming from CMPAfter a CMP, the samples must receive a special clean, because the slurry residues otherwise introduce contamination and particles.

Not Allowed
Ever been in EMLSamples from EML are never permitted to return to ICL or TRL

For more details or help, please consult PTC matrix, email, or ask the research specialist (Eric Lim)