Equipment
Lab and Coral NameICL / pTrack
ModelPicotrack
SpecialistPaul Tierney    (Scott Poesse)
Physical Location2F 3-South Photo
Classification
Process CategoryPhoto
SubcategoryCoat
Material KeywordsCMOS Metals, Photoresist, Developer
Sample Size6" Wafers
AlternativeTRL / coater
Keywordsmulti wafer, load lock, top side of sample, conformal dep, temperature, spinning substrate
Description
The PicoTrack is a wafer track that coats and develops photoresist. The resist coated is SPR700 and AZ5214E, which are also available at the coater in TRL. However, the coater track combines all of the HMDS, prebake, coat, EBR, and postbake steps. This results in a very fast, convenient and repeatable operation. Similarly, the developer track combines the post exposure bake, developing, and postbakes. The developing process here is more controlled than a manual dish developing at the wet bench in TRL. The coater track handles both red and green wafers, using different hotplates for each.

Best forFast and accurate coating and developing of 6" and 8" wafers for red and green processes
LimitationsProcessing of 6" and 8" wafers only.
Characteristics/FOMmulti wafer, cassette
Caution withMake sure to select the right recipe for red/green wafers
Machine Charges (academic rate)2pu/wafer
Documents

SOP
SOP Pico TrackSOP Pico Track
Resist RecipesBaseline resist recipes for TRL

Documents
SPR700Datasheet for SPR700 standard resist
PhotoresistApplication Note describing photoresist chemistry
Liftoff ResistApplication Note describing liftoff resists
CoatingApplication Note describing spincoating
Developing ResistApplication Note describing resist development

External Links
GuideMicroChem Application Notes
Process Matrix Details

Permitted
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
,
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.
,
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
,
PiecesWafer pieces may not be handled by the equipment, and are harder to thoroughly clean - preventing them from running in certain tools.
,
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.


For more details or help, please consult PTC matrix, email ptc@mtl.mit.edu, or ask the research specialist (Paul Tierney)