Lab Facilities and Setups

Most of the device fabrication and characterization is carried out at the IITB Nano Fab facility. Some specialized equipment and setups have been purchased/developed by our group.

Raith 150 Two

(A) IITB Nano Fab (Website)

We use this facility extensively for device fabrication and materials characterisation.

  • Electron Beam Lithography
  • Optical Lithography
  • Deposition tools – Sputter, Thermal/E-beam Evaporators, ALD
  • Plasma Ashing
  • RIE
  • High-Resolution XRD
  • XPS

(B) Optical Characterization Setup:

Photo-current measurement Setup
  • NKT Photonics SuperK supercontinuum laser with spectral output range of 390-2400 nm
  • Coherent OBIS 532 and 633 nm, 100 mW lasers
  • Newton 970 Scientific Camera DU970P-BVF EMCCD
  • Neutral density filters with optical densities ranging from 0.1 to 5
  • Olympus BX-63 microscope
  • Agilent function generator
  • Agilent four-channel digital oscilloscope with 4 GHz  bandwidth
  • Dual-bandwidth 3 MHz/500 kHz current probe for high-speed switching measurements
  • Agilent B1500A SMU

(C) 2D Materials heterostructure transfer setup:

Flake Transfer Setup

Consists of an Olympus BX 63 upright microscope, micromanipulator head, Thorlabs heater unit. A teflon stage with a heating unit is mounted on the microscope stage.

  • A glass slide with the PDMS stamp (which contains the flake to be transferred) is attached to the micromanipulator head
  • Typically, 20X or 50X long working distance objectives are used for the flake transfer process
  • Flakes are transferred by bringing the PDMS stamp in close contact to the desired substrate or another flake and heating to 60 ºC.
  • Alignment accuracy of +/- 4 micron and flakes of size 5-10 micron easily transferred.
  • Organic-residue free process.

 

(D) Gas sensing setup:

Linkam Stage

We have a high-precision gas sensitivity measurement setup.

  • Airtight leakproof sensing setup for safety of the lab personnel
  • Custom analyte gas mixtures possible
  • Precise variation in gas concentration ranging from 0.5 PPM to 1000 PPM
  • Linkam Stage for device probing and measurements
  • High-Resolution Agilent B1500A for electrical measurements
  • Measurement at different temperatures ranging from -196 to 420 °C possible

 

 

(E) Cryogenic probe station:

CRX-4K Probe Station

Features of the Model CRX-4K Probe Station:

  • Cryogen-free operation
  • Allows unsupervised cool down
  • Low-temperature operation
  • Minimize sample condensation during cool down
  • Using a self-contained closed cycle refrigerator (CCR), the CRX-4K will cool down to cryogenic temperatures unassisted, eliminating the need for monitoring by the researcher.
  • All standard CV and IV measurements can be performed on this versatile probe station.
  • Maximum sample size: 2inch x 2inch
  • Maximum no of probes: 4 probes, only dc measurement
  • Operating temperature range: 4.5K to 290K
  • Allowed temperature range: 290K to 77K. (Below 77K special permission is required from FIC)
  • Control stability:< 20K: +/- 50mK , 20K to 290K: +/- 20mK

(F) LabRAM HR Evolution Raman System

LabRAM HR Evolution

This system is used for Raman spectroscopy and micro-PL measurements.

  • Applications: Raman-PL (point measurement and mapping), temperature and bias-dependent Raman-PL
  • Detectors: Air cooled (-60 °C) Syncerity CCD-1, Liq. N2 cooled (-110 °C) InGaAs line symphony CCD-2
  • Software: Labspec6
  • Gratings: 1800 g/mm, 600 g/mm
  • Wavelength: 532 nm
  • Temperature Control: Linkam temp. controlled stage. Temp. range from (-196 °C) to (400 °C)

 

(G) planarGrow-2M 2-inch CVD Furnace

planarGrow CVD system

Features of the planarGrow-2M 2-inch CVD system:

  • Single zone furnace connected to PID heater controller
  • Heating jacket connected to digital temperature controller
  • LN2 cold trap
  • Gases used: Ar, N2, FGA, H2 (100 %), H2S (100 %).
  • Materials: 1L WSe2 flakes, few-layer MoS2 flakes, wafer scale MoS2 film (1 cm x 1 cm).

(H) Computational Facilities:

Atomistic modeling and quantum transport calculations are carried out using the software package ‘Synopsys_ QuantumATK’.

  • QuantumATK+ NEGF Academic License
  • In-house quantum ballistic simulator (QBS)
  • High end servers:
  1. Intel Xeon E5 2650V3 processor / 2 × 10 core 2.3GHz /8 × 16GB DDR4 ECC Reg. RAM
  2. Intel Workstation bare bone system / 2 × 8 core 2 to 2.8 GHz / 12 × 8 GB DDR3 1600 MHz RAM