1. III-V
1.1. properties
1.2. applications
2. silicon
2.1. applications
2.1.1. mems/nems
2.1.1.1. mechanical stress testing
2.1.1.2. pressure sensor
2.1.1.3. biomimetic
2.1.1.3.1. mems sensor flow-related controll
2.1.1.4. acceleration sensor: pull-in instability of paddle-type nems sensor
2.1.2. electronics
2.1.2.1. transistor
2.1.2.1.1. logic transistor
2.1.3. self-assembly milli to nano scale
2.2. properties
2.2.1. mechanical
2.2.1.1. gauge factor: 200
2.2.1.2. young's modulus: 130-188 GPa
3. MoS2
3.1. properties
3.1.1. piezoelectricity: piezoelectric coefficient: e11 = 2.9 × 10–10 C m−1
3.1.1.1. piezoelectricity of singl layer mos2 for energy conversion and piezotronics
3.1.2. electrical
3.1.2.1. screening
3.1.2.2. bandgap: intrinsic direct 1.8 eV indirect bandgap 1.2 eV
3.1.2.2.1. bilayer
3.1.2.2.2. strain induced bandgap tuning
3.1.2.3. mobility @ RT: 200 cm^2/Vs
3.1.2.4. on/off ration: 1x10^8
3.1.2.5. doping
3.1.2.6. electrical properties on hBN
3.1.2.7. effect of interlayer coupling on electrical properties
3.1.3. mechanical
3.1.3.1. thickness: 0.65nm
3.1.3.2. mechanical
3.1.3.3. pressure confinement effect
3.1.3.4. strain effect on effective mass
3.1.3.5. gauge factor
3.1.3.5.1. bi-layer: 230
3.1.3.5.2. bulk: 200
3.1.3.6. uniaxial and biaxial strain
3.1.3.7. wettability
3.1.3.8. friction
3.1.4. optical
3.1.4.1. electroluminescence
3.1.4.2. raman spectroscopy
3.1.4.2.1. MoS2 488nm laser
3.1.5. heat conductance: 7.45 W/mK @ 300K suspended monolayer: 34 W/mK suspended multilayer: 52 W/mK
3.1.6. chemical
3.1.6.1. one layer of Mo -sandwiched between two layers of S by covlent bonding packed in hexagonal arrangement
3.1.6.2. sheets held together by weak van der Waals interaction
3.1.6.3. lattice constant: 3.160 Å
3.1.7. thermal
3.2. application
3.2.1. chemical vapor sensor (comparison with graphene devices)
3.2.2. transistor
3.2.2.1. channel
3.2.2.2. contacts
3.2.2.2.1. injet printed Ag contacts
3.2.2.3. CVD grown
3.2.2.3.1. multilayer
3.2.2.3.2. single layer
3.2.2.4. flakes
3.2.2.4.1. single layer
3.2.2.5. flexible transistor
3.2.2.5.1. on polyimide
3.2.2.6. charge trapping at the interface
3.2.2.7. thin film transistor
3.2.2.8. strain sensing
3.2.2.9. self-screened transistor with bottom graphene electrode
3.2.2.10. transfer characteristics
3.2.2.11. suspended transistor
3.2.2.12. intrinsic origin of the hysteresis suspended mos2
3.2.3. supercondictivity
3.2.4. MEMS/NEMS
3.2.4.1. membrane
3.2.4.1.1. resonator
3.2.4.1.2. nanopores open atom by atom
3.2.4.1.3. direct and scalable CVD membranes
3.2.4.1.4. hydrogen separation
3.2.4.1.5. water desalination
3.2.4.2. flexible MoS field-effect transistor for gate-tunable strain sensor
3.2.4.3. bio/medicin
3.2.4.3.1. review: bio sensors
3.2.4.3.2. functionalication rection between mos2 and thiole
3.2.4.4. sensors
3.2.4.4.1. synthesis and sensor applications of mos2-based nanocomposites
3.2.4.4.2. gas sensor
3.2.4.4.3. tactile sensor for electronic skin
3.2.4.5. bending response theory
3.2.5. sensing
3.2.6. supercapacitor
3.2.6.1. MoS2-Graphene composite coin cell supercapasitor
3.2.7. heterostructure
3.2.7.1. electric-field and strain-tunable mos2/h-bn/graphene vertical heterostructure
3.2.7.2. review
3.2.7.3. one-dimensional electrical contacts to mos2 heterostructure
3.3. contacting
3.3.1. graphene electrode
3.3.2. contact resistance
3.3.3. carrier transport at the metal-mos2 interface
3.3.4. metal contacts
3.3.5. vam der waals interaction and lattice mismetch at mos2/metal interfaces
3.3.6. chromium as ideal contact metal
3.4. transfer
3.4.1. wet etch method
3.4.1.1. BOE etch
3.4.1.1.1. spin-coat: ar-p 649.04 [email protected],2 etch SiO2 with BOE
3.4.1.2. NaOH etch
3.4.1.2.1. spin-coat: ar-p 649.04 [email protected],2 etch SiO2 with NaOH
3.4.1.3. KOH etch
3.4.1.3.1. spin-coat: ar-p 649.04 [email protected],2 cratch the corners of the chip place a drop of KOH etch sio2
3.4.2. ultrasound method
3.4.3. pdms stamp
3.4.3.1. mos2 flake
3.4.3.2. polymer free large-area transfer for transistors fragmented mos2
3.4.4. fast Seak and peal in water drop with Polysterene in Touluene polymer
3.4.5. exfoliation
3.4.5.1. liquid phase exfoliation
4. fabrication processes
4.1. Evaporation
4.2. Sputtering
4.3. Wet etching
4.3.1. copper
4.3.1.1. Sodiumpersulfate 20g/500ml H2O
4.3.1.2. FeCl3 8%: 20g FeCl3 + 230g H2O
4.3.2. sio2
4.3.2.1. Buffered oxide etch (BOE) 5:1 Buffered oxide etch (BOE), 5:1 Buffered HF, (5 40% NH4F:1 49%HF): 100 nm/min (thermal oxide)
4.3.2.2. concentrated HF (49%)
4.3.2.3. 10:1 HF 10 H2O: 1 HF: 23nm/min (thermal oxide)
4.3.2.4. HF vapor HF + H2O vapor, 1cm over dish with 49% HF: 66 nm/min (thermal oxide)
4.3.3. silicon nitride (Si3N4)
4.3.3.1. Buffered oxide etch (BOE), Buffered HF 5:1 Buffered oxide etch (BOE), 5:1 Buffered HF, (5 40% NH4F:1 49%HF): 60 nm/min (PECVD)
4.3.3.2. phosphoric acid
4.3.4. Si
4.3.4.1. KOH Isotropic, 30% by weight, 80°C: 1100 nm/min
4.3.5. poly si
4.3.5.1. KOH Isotropic, 30% by weight, 80°C: >1000 nm/min
4.3.6. Aluminum
4.3.6.1. KOH 30% by weight, 80°C: >800 nm/min
4.4. Dry etching
4.4.1. graphene
4.4.1.1. RIE: O2 80sccm O2 57mtorr 80W 20s
4.4.2. sio2
4.4.2.1. RIE: CF4 +O2 60mtorr 100W 44 nm/min (thermal oxide)
4.4.2.2. RIE: SF6 + Ar 40sccm SF6 30sccm Ar 10mtorr 50W 33nm/min
4.4.3. si
4.4.3.1. RIE: SF6 + Ar 40sccm SF6 30sccm Ar 10mtorr 50W 1500nm/min
4.4.4. Si3N4
4.4.4.1. RIE: SF6 + Ar 40sccm SF6 30sccm Ar 10mtorr 50W 150nm/min
4.4.5. mos2
4.4.5.1. RIE: BCl3 + Ar 15sccm BCl3 60sccm Ar 0.6 Pa 50W 5min
4.4.5.2. RIE: Ar coupled plasma RIE (CCP-RIE) 100 sccm Ar 10 Pa 50W > 90s
4.4.5.3. Layer by layer etching with cl and ar
4.5. Photolithography
4.5.1. photoresists
4.5.1.1. positive exposed to light becomes soluble unexposed remains insoluble
4.5.1.1.1. SPR 700-1.2
4.5.1.1.2. LOR 5A
4.5.1.2. negative exposed to light becomes insoluble unexposed is dissolved by developer
4.5.1.2.1. OSTE+
4.5.1.2.2. SU-8
4.5.2. systems
4.5.2.1. karl suss MJB-3 mask aligner
4.5.2.2. karl suss MA6/BA6 mask aligner
4.6. E-beam lithography
4.6.1. e-beam resists
4.6.1.1. negative exposed to e-beam becomes insoluble unexposed is dissolved by developer
4.6.1.1.1. AZ nLof 2007
4.6.1.1.2. su-8
4.6.1.2. positive exposed to e-beam becomes soluble unexposed remains insoluble
4.6.1.2.1. AR-P 679.02
4.6.1.2.2. AR-P 649.04
4.6.1.2.3. AR-P 617.14
4.6.2. systems
4.6.2.1. Raith
4.6.2.2. FEI + Raith Elphy Quantum
4.6.3. graphene fabrication
4.6.4. graphen small hole kitting
4.7. Plasma enhanced chemical vapor deposition (PECVD)
4.8. Critical point drying (CPD)
4.9. atomic layer deposition (ALD)
4.9.1. graphene
4.9.1.1. selective deposition of al2o3 on graphene
4.9.2. mos2 self-limiting
4.10. annealing
4.10.1. rapid thermal annealing (RTA)
4.10.2. forming gas annealing
4.10.2.1. system
4.10.2.1.1. hereus oven
4.10.3. remove PMMA (200nm): Haereus oven ramp: 10°C/min 450°C for 1h Ar/H2 (5%) (3 l/min / 0.1 l/min)
4.11. wafer dicing
4.12. spin-coating
4.13. synthesis
4.13.1. chemical vapor deposition (CVD)
4.13.1.1. Thermal chemical vapor deposition (thermal CVD)
4.13.1.1.1. graphene
4.13.1.1.2. mos2
4.13.1.1.3. TMDs
4.13.1.1.4. hBN
4.13.1.2. Plasma enhanced chemical vapor deposition (PECVD)
4.13.1.2.1. graphene
4.13.2. graphene synthesis directly on polymer
4.13.2.1. FET as carbon source patterned 30nm Ni layer as catalysator laser treatmentfor direct synthesis
4.13.3. lpcvd
4.13.3.1. large-area hbn
4.13.4. molecular beam epitaxy
4.13.4.1. graphene
4.13.4.1.1. on hBN
4.13.4.2. visualization of grain sturcture of 2d materials
5. analytics
5.1. Atomic force microscope (AFM)
5.1.1. systems
5.1.1.1. PSIA XE-100
5.1.1.1.1. tapping mode (dynamic force microscopy): - use NC-mode and NC-tip - at 5kHz adjust drive that resonance peak is in y-units 1-3 - set-point a little left of resonance peak - line set-point bit higher than half the resonance peak height best parameters: - gain: 2.2 - scan speed: 0.7 Hz
5.1.1.1.2. non contact mode (nc-mode): - use NC-mode and NC-tip - at 5kHz adjust drive that resonance peak is in y-units 1-3 - set-point a little right of resonance peak - line set-point bit higher than half the resonance peak height best parameters: - gain: 2.2 - scan speed: 0.3 Hz
5.2. scanning electron microscope (SEM)
5.3. focused ion beam (FIB)
5.4. Raman Spectroscopy
5.4.1. graphene 532nm and 633 nm laser
5.4.1.1. single layer spectrum
5.4.1.1.1. D-peak: defect peak ~1350 cm^-1
5.4.1.1.2. G-peak (4x 2D-peak): ~1580 cm^-1
5.4.1.1.3. 2D- peak: ~2700 cm^-1
5.4.1.2. multilayer spectrum
5.4.1.2.1. 5+ layer not distinguishable from graphite
5.4.1.3. suspended graphene
5.4.1.3.1. probing mechanical properties of graphene
5.4.1.3.2. ripple formation in suspended graphene
5.4.1.3.3. strain effect on suspended graphene by polarized raman
5.4.1.3.4. probing charged impurities in suspended graphene
5.4.1.3.5. intrinsic properties of exfoliated free-standing graphene
5.4.1.3.6. raman of graphene and bilayer under biaxial strain (bubbles)
5.4.1.3.7. uniaxial strain on graphene
5.4.1.3.8. elastic properties of suspended graphene
5.4.1.3.9. raman spectroscopy and kelvin force probe microscopy
5.4.1.3.10. temperature
5.4.1.4. on substrate graphene
5.4.1.4.1. nanometer-scale strain variation in graphene
5.4.1.4.2. interface coupling in twisted multilayer graphene
5.4.1.4.3. rayleigh imaging of graphene and graphene layers
5.4.1.4.4. spacially resolved raman of single- and few-layer graphene
5.4.1.4.5. graphene fingerprint
5.4.1.4.6. thickness-dependent native strain
5.4.1.4.7. surface-enhanced raman scattering of hybrid structures with ag nanoparticles ans graphene
5.4.2. MoS2 488nm laser
5.4.2.1. 382.9 cm^-1 406.0 cm^-1
5.4.2.2. on hBN
5.4.2.2.1. raman shift
5.4.2.3. mos2 on substrate
5.4.2.3.1. shift in electron irradiated monolayer
5.4.3. hBN
5.5. Keithley SCS 4200 Parameter Analyzer
5.6. Light Microscope
5.6.1. light field
5.6.2. dark field
5.7. Elipsometry
5.8. Laser confocal microscope
5.8.1. brands
5.8.1.1. Olympus LEXT OLS4100
5.9. probe station
5.9.1. Lakeshore cryo probestation
6. hexagonal boron nitride (hBN)
6.1. porperties
6.1.1. impermeability to everything except to protons
7. carbon nanotubes
7.1. properties
7.2. applications
7.2.1. mems/nems
7.2.1.1. switch
7.2.1.2. pressure sensor
7.2.1.2.1. pmma based
7.2.2. electronics
7.2.2.1. transistor
7.2.2.1.1. logic transistor
7.3. synthesis
8. graphene
8.1. transfer
8.1.1. wet-etch method
8.1.1.1. dry transfer with spacer substrate
8.1.1.2. copper on sio2 pattern graphene underetch copper leave graphene on sio2
8.1.2. cleaning
8.1.2.1. dry-cleaning with active graphite
8.1.2.2. polymer scaffolds
8.1.2.3. thermal annealing at 300°C for 3 hours under UHV
8.1.2.4. metal cleaning, crackless, wrinkleless
8.1.2.5. acetic acid and methanol
8.1.2.6. residue reduction
8.1.3. exfoliation
8.1.3.1. on SiC
8.1.3.2. liquid phase exfoliation
8.1.3.3. polymer nanoparticles assisted exfoliation
8.1.4. nano imprint
8.1.5. glue on substrate
8.1.5.1. epoxy
8.1.6. copper evaporation
8.1.7. carbon atom diffusion through copper
8.1.8. large area patterning transfer with holographic lithography
8.1.9. polymer assisted
8.1.9.1. polymer free transfer with cellulose acetate
8.1.9.2. dry PI polymer transfer (copper reuse)
8.1.9.3. roll-to-roll transfer method
8.1.9.4. pet assisted transfer method
8.1.9.5. soak and peel method
8.1.9.6. dry pdms stamp transfer
8.1.9.6.1. pdms stamp with o2 plasma before stamp on cu foil: 30W, 15s O2 plasma enhance adhesion
8.1.9.6.2. pdms transfer without pmma pdms remove by methylene chloride
8.1.9.6.3. large area suspended graphene transfer with pdms
8.1.9.6.4. low temperature, metal assisted
8.1.9.7. dry thermal release tape
8.1.9.8. vacuum assisted transfer -remove of adsorbants - use standard wet transfer
8.1.9.9. pmma and ab-glue
8.1.9.10. spin-coater assisted transfer to polymer substrate
8.1.9.11. resiude fre pmma remove with ar+ ion beam
8.1.10. by oxidation-assited water intercalation
8.1.11. etch free-transfer
8.1.11.1. transfer free suspended graphene
8.1.11.2. electrochemical transfer method
8.1.11.2.1. bubble method
8.1.11.2.2. agarose gel method
8.1.11.2.3. pdms assisted without pores
8.1.11.2.4. electro-exfoliating grapene from graphite
8.1.11.2.5. bubble transfer with polymer support with inclosed air bubble
8.1.11.3. polyvinyl alcohol (PVA) film
8.1.11.4. dry-transfer
8.1.11.4.1. dry transfer with bN
8.1.11.4.2. selective dry transfer
8.1.11.4.3. dry electrostatic method
8.1.11.5. water-mediated and instataneous transfer
8.1.12. support free transfer with SAM modified substrate
8.1.13. wetting assisted transfer
8.1.14. polymer free transfer
8.1.14.1. graphene growth on patterned mo and removal of ma with sulfuric acid
8.1.14.2. with Ti as transfer layer removed with hf
8.1.14.3. using hexane
8.2. properties
8.2.1. mechanical
8.2.1.1. intrinsic strength: prestine graphene 90 - 121 GPa (30 N/m)
8.2.1.1.1. defective graphene ~50 GPa (18 N/m)
8.2.1.1.2. policrystalline
8.2.1.2. young's modulus: prestine and cvd graphene 1 TPa
8.2.1.3. Stretchability: 20%
8.2.1.4. impermeability to everything but protons
8.2.1.5. strain
8.2.1.5.1. uniaxual strain - deformation
8.2.1.5.2. uniaxial strain in bilayer graphene unisotropic phonon softening
8.2.1.6. Thickness: 0.34 nm
8.2.1.7. defect introduction through Argon irradiation
8.2.1.8. crack propagation
8.2.1.8.1. self healing of cracks
8.2.1.8.2. fracture of graphene (review)
8.2.1.9. wet adhesion
8.2.1.10. adhesion
8.2.1.10.1. strong adhesion to sio2
8.2.1.10.2. weak adhesion on pdms --> low surface energy
8.2.1.10.3. temperature-dependent adhesion on a trench
8.2.1.11. suspended
8.2.1.11.1. <10nm thick graphene: spring constant: 1-5 N/m
8.2.1.12. critical temp and radus for buckling
8.2.1.13. topography
8.2.1.14. small scale pull-in instability and vibration
8.2.1.15. gauge factor
8.2.1.15.1. exfoliated graphene
8.2.1.15.2. cvd graphene
8.2.2. electrical
8.2.2.1. high electron mobility
8.2.2.1.1. on bulk
8.2.2.1.2. suspended prestine at room temperature: 230000 cm2/Vs
8.2.2.1.3. suspended low temperature: order of 1000000 cm2/Vs
8.2.2.1.4. mobility extraction
8.2.2.1.5. CVD graphene on hBN: 350000 cm^2/Vs
8.2.2.1.6. CVD-graphene
8.2.2.1.7. exfoliated
8.2.2.2. screening
8.2.2.2.1. on hBN
8.2.2.3. electrical field
8.2.2.4. electrostatic
8.2.2.5. sheet resistance: 500 Ohm/square (wet transfer)
8.2.2.5.1. multilayer
8.2.2.5.2. depending on transfer
8.2.2.6. band structure
8.2.2.6.1. bandgap
8.2.2.7. breakdown current density
8.2.2.7.1. nanoribbons: width 16nm: 10^8 A/cm^2
8.2.2.8. effect of humidity on electrical properties
8.2.2.9. effect of interlayer coupling on electrical properties
8.2.2.10. surface electrical properties
8.2.3. optical
8.2.3.1. transparency: mono layer 97.7%
8.2.3.1.1. multilayer
8.2.3.1.2. fine structure constant
8.2.3.2. reflection: few layer: <0.1% > 10 layer: 2%
8.2.3.3. absorption: 300 - 2500 nm peak at 270 nm
8.2.3.4. photoresponse
8.2.3.5. raman
8.2.3.5.1. graphene 514nm and 633 nm laser
8.2.3.6. absorption: 2.3%
8.2.4. piezoresistivity
8.2.4.1. positive piezoconductive
8.2.5. chemical
8.2.5.1. hexagonal honeycomb lattice of carbon atoms in sp2 hybridization
8.2.5.2. remaining pz forms C-C pi bond
8.2.5.3. two atom A and B unit cell
8.2.5.4. superhydropobic graphene
8.2.5.4.1. superhydrophobic to superhydrophilic
8.2.5.5. intersurface interaction
8.2.6. thermal
8.2.6.1. exfoliated graphene
8.2.6.1.1. suspended heat conductivity: 5150 W/mK
8.2.6.1.2. thermal conductvity of suspended graphene with defect graphene
8.2.6.1.3. heat transport
8.2.6.1.4. thermal expansion coefficient: -7 × 10−6 K−1
8.2.6.2. CVD-graphene
8.2.6.2.1. suspended heat conductivity: 5150 W/mK
8.3. applications
8.3.1. mems/nems
8.3.1.1. membrane
8.3.1.1.1. pressure sensor
8.3.1.1.2. switch
8.3.1.1.3. accelerometer
8.3.1.1.4. loudspeaker
8.3.1.1.5. resonator
8.3.1.1.6. memory device
8.3.1.1.7. detection
8.3.1.1.8. with local gate control
8.3.1.1.9. electricity generation
8.3.1.1.10. TMD growth on suspended graphene
8.3.1.1.11. suspended graphene
8.3.1.1.12. membrane fabrication with tunable structures
8.3.1.1.13. strain sensor
8.3.1.1.14. microphone
8.3.1.1.15. fabrication
8.3.1.1.16. bio and medicin
8.3.1.1.17. characterization
8.3.1.1.18. properties
8.3.1.1.19. water desalination using nanoporous graphene
8.3.1.2. piezoelectric strain gauge
8.3.1.3. force sensor
8.3.1.4. nano bots
8.3.1.5. mechanical control of graphene on pyramidal structures
8.3.1.6. mos2 chemical vapor sensor (comparison with graphene devices)
8.3.1.7. hall sensor
8.3.1.7.1. quantum hall effect
8.3.1.8. transparent micro heater
8.3.1.9. tactile sensing with array of graphene woven nanofabrics
8.3.1.10. chemical sensor
8.3.1.10.1. gas sensor
8.3.1.11. control of nitrogen-vacancy defect emission
8.3.1.12. bio
8.3.1.12.1. bioanalytical applications
8.3.1.12.2. biosensor
8.3.1.12.3. bio-inspired strain sensors
8.3.1.12.4. biomedical applications
8.3.1.13. pressure sensor
8.3.1.13.1. pressure sensor with si3n4 membare and graphene strain elements
8.3.1.13.2. biomedical pressure sensor
8.3.1.13.3. electronical skin high speed rapid response criss cross graphene pattern
8.3.1.14. strain sensor for human motion monitoring
8.3.1.15. micromechanics
8.3.1.15.1. measurement of nanocrystalline graphnee
8.3.2. electronics
8.3.2.1. transistor
8.3.2.1.1. bilayer transistor
8.3.2.1.2. nanoribbon transistor
8.3.2.1.3. rf transistor
8.3.2.1.4. gbt (tunneling transistor)
8.3.2.1.5. Graphene field-effect device (GFET)
8.3.2.1.6. characterisation
8.3.2.1.7. terahetz detector
8.3.2.1.8. flexible
8.3.2.1.9. large scale integration
8.3.2.1.10. suspended
8.3.2.2. diode
8.3.2.3. circuits
8.3.2.3.1. flexible
8.3.2.4. solar cells
8.3.2.4.1. graphene molecules
8.3.2.5. supercapacitor
8.3.2.5.1. flexible
8.3.2.5.2. 3d graphene-based for application in supercapacitors
8.3.2.6. flexible electronics
8.3.2.6.1. tunable filed effect properties - low k-dielectric
8.3.3. folding
8.3.3.1. liquid evaporation driven
8.3.4. composite materials
8.3.4.1. graphene polymer Transparent, Flexible, and Conducting Films
8.3.5. optics
8.3.5.1. optoelectonics
8.3.5.1.1. photodetector
8.3.5.1.2. selectively enhanced photocurrent on twisted bilayer
8.3.5.2. photonics
8.3.5.3. light emission from graphene
8.3.5.3.1. nanocrystalline graphene
8.3.5.4. macroscopic and direct light propulsion of bulk graphene
8.3.6. heterostructures
8.3.6.1. graphene/hBN
8.3.6.2. electric-field and strain-tunable mos2/h-bn/graphene vertical heterostructure
8.3.6.3. graphene based heterostructure
8.3.7. superhydrphobic graphene
8.3.8. high temperature thin film devices
8.3.9. filtration and desalination of water
8.3.10. sensing
8.3.11. contacts
8.3.11.1. flexible
8.3.12. stability of few layer graphene doped with gold chloride
8.4. contacting
8.4.1. as electrode for mos2
8.4.2. interconnects
8.4.3. contact resistance
8.4.4. bottom graphene electrode
8.5. review
8.6. passivation
8.7. mulitlayer graphene
8.7.1. layer-by-layer stacking
8.7.1.1. stacking on copper without removing top pmma
8.7.1.2. stacking and removing pmma on substrate layer-by-layer
8.7.1.3. problem: increasing roughness
8.7.2. bernal stacked
8.8. graphene oxid (GO)
8.8.1. properties
8.8.1.1. mechanical
8.8.1.1.1. young's modulus: 0.15 +- 0.03 TPa
8.8.1.1.2. intrinsic strength: 4.4 +- 0.6 GPa (3.1 +- 0.4 N/m)
8.8.1.1.3. thickness: 0.7 nm
8.8.2. application
8.8.2.1. membrane
8.8.2.1.1. oil and water separation
8.9. graphene ink
8.9.1. properties
8.9.1.1. improve by laser-annealing
8.10. analytics
9. theory
9.1. electrical
9.1.1. resistivity: ρ = R * A / l = [ Ωm] ρ: resistivity R: resistance A = w * t: cross section area = width * thickness l: length most used: Ωmm, Ωµm
9.1.2. capacitance: C = ε_0 * ε_r * A / h = [F] C: capacitance ε_0: permitivity ε_r: relative permitivity A: area h: plate distance
9.1.2.1. dieelectric capacitance: C = ε_0 * ε_r / t_ox = [F] C: capacitance ε_0: permitivity ε_r: relative permitivity t_ox: oxide thickness
9.1.3. pull-in voltage: V_pull-in = sqrt(2/3)^3 * (k * h^3 / ε_0 * ε_r *A)) V_pull-in: pull-in voltage k: spring constant h: plate distance ε_0 permitivity ε_r: relative permitivity A: area
9.1.4. electron mobility (graphene): µ = (L / W) * g_m / C_ox * V_ds µ: mobility L: channel length W: channel width g_m provided by keithley g_m = dI_ds/dV_g at each V_gs point is calculated for each g_m point g_m = I_ds / ( V_gs - V_d) or for each g_m point g_m = (y2-y1)/(x2-x1) V_ds: source-drain voltage C_ox: oxide capacitance C_ox = ε_0 * ε_r / d_ox ε_0 permitivity ε_r: relative permitivity d_ox: oxide thickness
9.1.5. gate leakage: - parallel shift of the curve indicates a gate leakage - always check I_gate and plot it while measurement
9.2. mechanical
9.2.1. mechanical stress: σ = F / A = [N/m^2] σ: mechanical stress F: force A = w * t: cross section area = width * thickness
9.2.2. mechanical strain: ε = σ / E = s / l = [ ] ε: mechanical strain σ: mechanical stress E: young's modulus s: displacement due to mechanical strain l: length
9.2.3. force
9.2.3.1. Force (related to mechanical stress): F = A * E * ε = [N] F: force A = w * t: cross section area = width * thickness ε: mechanical strain
9.2.3.2. electrostatic force: F = 1/2 * ε_0 * ε_r * A * (V^2 / h^2) = [N] F: eletrostatic force ε_0: permitivity ε_r: relative permitivity A: area V: voltage h: plate distance
9.2.4. gauge factor: η = ΔR / ε * R η: gauge factor ΔR: change in resistance R: resistivity ε: strain: ε = (P * L / µ)^2/3 ε: strain P: pressure L: length of cavity µ: graphene shear modulus (150 N/m) --> ΔR / R = η (P * L / µ)^2/3
9.3. circuits
9.3.1. types
9.3.1.1. ring oscilator - series of at least 3 inverters (inverter: nmos+pmos) - final output of the last is inertial input in the first - final output is inverted of the inertial input - channel takes some time to charge - oscillation starts spontaneously - increase of frequency: 1. increase applied voltage 2. smaller number of inverters
9.3.1.2. inverter - 1 nmos and 1 pmos together - input voltage is inverted
9.4. units
9.4.1. electrical
9.4.1.1. E- field: N / C = V / m = kg * m / s^3 * A
9.4.1.2. Volts: V = W / A = m^2 * kg / s^3 * A
9.4.1.3. Farad: F = C / V = s^4 * A^2 / m^2 * kg
9.4.1.4. Ohm: Ω = V / A = m^2 * kg / s^3 * A^2
9.4.1.5. Coulomb: C = A * s
9.4.2. mechanical
9.4.2.1. Pascal: Pa = N / m^2 = kg / m * s^2
9.4.2.2. newton: N = m * kg / s^2
9.4.2.3. Watt: W = J / s = m^2 * kg / s^3
9.4.2.4. Joule: J = N * m = m^2 * kg / s^2 = eV * C
9.5. optical
9.5.1. wavenumber: k = 2 * π / λ = [1 / m] k: wavenumber λ: wavelength
9.5.2. wavelength: λ = 1.24 / h * ν = [µm] λ: wavelength hν: energy in eV
9.6. constants
9.6.1. mechanical
9.6.1.1. speed of light: c = 2.9981e8 m/s
9.6.1.2. atomic mass unit: u = 1.66e-27 kg
9.6.1.3. boltzmann's constant: k = 1.38e-23 J/K = 8.62e-5 eV/K
9.6.1.4. electron rest mass: m_0 = 9.11e-31 kg m_o c^2 = 5.11e5 eV
9.6.1.5. proton rest mass: m_p = 1.67e-27 kg m_p c = 9.38e8 eV
9.6.1.6. neutron rest mass: m_n = 1.67e-27 kg m_n c^2 = 9.38e8 eV
9.6.1.7. planck's constant: h = 6.63e-34 Js = 4.41e-15 eVs ћ = 1.05e-34 Js = 6.58e-16 eVs
9.6.1.8. avogadro's number: N_A = 6.02e23 molecules/mole
9.6.1.9. energy at room temperature: kT = 0.0259 eV = 4.11e-21 J = 9.83e-22 cal = 4.114 pN * nm
9.6.2. electrical
9.6.2.1. elementary charge: q = 1.602e-19 C
9.6.2.2. permittivity: ε_0 = 8.85e-12 F/m = 8.85e-15 F/cm
9.6.3. optical
9.7. midnight formula: x_1/2 = -b +- sqrt(b^2 - 4 * a * c)/2 * c
10. packaging
10.1. pressure sensor
10.1.1. polymer package
11. OSTE+
11.1. application
11.1.1. robust microdevices
11.1.2. improved photo structuring
12. WSe2
12.1. applications
12.1.1. light emitting tunneling transistor
13. WS2
13.1. properties
13.1.1. optical
13.1.1.1. photolminescence
13.2. contacting
13.2.1. chromium as ideal contact metal
13.3. applications
13.3.1. photodetector
13.3.2. mems/nems
13.3.2.1. gas sensor
13.3.2.2. humidity sensor
14. other material
14.1. applications
14.1.1. suspended
14.1.1.1. ru nanosheets for water splitting
14.1.2. mems/nems
14.1.2.1. pressure sensor
14.1.2.1.1. flexible pressure sensor based on pdms and elastomer film
14.1.2.2. gas sensor
15. off-topic
15.1. nanotechnology
15.1.1. nanotechnology solutions for global water challenges