Microsystems laboratory

The microsystems capabilities of IMB-CNM are included into the Integrated Micro and Nanofabrication Clean Room.

Surface: 25 m².
Class 10000 with class 1000 in the wet processing stations.

Wet etching:

Bulk silicon micromachining (anisotropic wet etching)
Surface silicon micromachining
Metals wet etching: chrome, titanium, nickel, gold, tungsten, isotropic etching of silicon
Dielectrics wet etching: silicon oxide, hafnium oxide
Glass micromachining by HF-based solutions

Lift-off process: Patterning of metal layers without wet etching.

Deposition of metals:

Porous silicon: Electrolic etching of silicon

Wafers bonding:

	Wet etching and cleaning: 2 Chemical benches one for CMOS compatible wafers and another for wafers with contaminant metals 4 heated baths for anisotropic wet etching of silicon in alkaline solutions 4 multipurpose baths for metal etching and chemical depositions of metals 4 overflow rinse tanks for wafer cleaning and 2 nitrogen guns for wafer drying
	Lift off: 3 ultrasonic baths Gas cabinet
	Metals deposition: 2 baths for the chemical deposition of metals by Elelctroless Gas cabinet for electroplating processes Autolab to control the electrochemical processes
	Porous silicon: Bath for the porosification of silicon Gas cabinet
	Anodic bonding: Suss Microtech Sb6e
	Critical point dryer of CO₂: Automegasandri 915 B@Tousimis
	Small equipment: Spinner Laurell WS400A, 2 hot plates, magnetic stirrer, orbital stirrer, minishaker, centrifuged
	Test equipments: Optical microscope Stereoscope microscope Optical perfilometer

Anisotropic wet etching of Silicon for bulk micromachining in alkaline solutions. KOH and TMAH are used as etching solutions. SiO₂ and Si₃N₄ are used as mask layers during the etching. Four different etch-stop methods are available.
Surface micromachining of silicon. Polysilicon is used as structural layer meanwhile the silicon oxide acts as sacrificial layer. HF-based solutions are used as etchants for the sacrificial layar etching. The process can be also done by HF-vapors. After the eching the samples can be dryed by critical point dryer of CO2 to avoid the sticking of the released structures.
Lift-off process. Patterniing of metallic layers withou chemical etching of the layer. The process can be performed for metals deposited by evaporation or even by sputtering.
Chemical deposition of metals by Electroless. Available metals are nickel, gold and copper.
Electrodeposition of metals by electroplating. Available metals are nickel, gold, copper, tin-silver, silver
Porous silicon. Electrochemical etching of silicon
Wet etching of metal. Wet etching of chrome, aluminium, titanium, nickel, gold, tungsten
Wafers bonding. Available process anodic bonding (silicion-galss), fusion bonding (silicon-silicon) and eutectic bonding (silicon-gold)