Data from: Tungsten oxide adhesion layer for low resistance hole contacts to Wse2
Data files
Mar 23, 2026 version files 459.87 KB
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Energy_Band_on_WSe2_WOx_and_Ti.xlsx
150.91 KB
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MoSe2_IDVG_and_R.xlsx
18.01 KB
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README.md
12.17 KB
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WOx_top_gate.xlsx
14.49 KB
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WSe2_AFM_measurements.xlsx
17.47 KB
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WSe2_IDVG_and_R.xlsx
29.57 KB
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WSe2_Raman.xlsx
17.74 KB
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WSe2_TLM1.xlsx
51.11 KB
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WSe2_TLM2.xlsx
21.47 KB
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XPS_evaporated_Ti_WOx.xlsx
86.24 KB
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XPS_WSe2_WOx_stack.xlsx
40.69 KB
Abstract
The dangling bond-free surfaces of transition metal dichalcogenides (TMDs) fundamentally challenge the creation of strongly bonded metal contacts. Commonly used interfacial adhesion layers, such as titanium have unfavorable band alignment to the valence band of TMDs. Here, we introduce tungsten oxide (WOx) as an interfacial adhesion layer for low-resistance hole contacts on monolayer WSe2. We show that the WOx adhesion layer exhibits a two-fold increase in adhesion force on both WSe2 and SiO2 surfaces compared to the conventional titanium adhesion layer while enabling a low hole contact resistance of Rc = 0.2 kΩ⋅μm on monolayer WSe2. This work provides a way to facilitate a robust and reliable way to create highly adhesive contacts on atomically smooth TMD surfaces suitable for large-scale integration.
Dataset DOI: 10.5061/dryad.p5hqbzm2m
Description of the data and file structure
This dataset contains the source data underlying the main figures and supporting information for the paper titled "Tungsten Oxide Adhesion Layer for Low Resistance Hole Contacts to WSe2." The electrical characterization data includes ID-VBG, ID-VD, and ID-VTG measurements for back-gated and top-gated FETs on WSe2 and MoSe2, utilizing both Ti and WOx adhesion layers. Additionally, it contains ID-VD measurements for two distinct TLM structures on WSe2 with WOx/Au contacts. Beyond electrical transport, the dataset provides material characterization data such as XPS spectra for Ti, WOx, and WSe2/WOx stacks. It also includes Raman shift analysis of WSe2 before and after WOx evaporation and energy band alignments for Metal/WO3/WSe2 versus Metal/Ti/WSe2 interfaces. Finally, the repository includes AFM-based adhesion force measurements comparing Ti and WOx coated tips on monolayer WSe2 and SiO2 substrates.
Files and variables
File: MoSe2_IDVG_and_R.xlsx
Description: Contains ID - VBG measurements on monolayer MoSe2 using WOx - Rh and Ti - Rh contacts. With VD = -1 V, Lch = 2 μm. Also contains the calculated resistance of MoSe2 devices as a function of the WOx and Ti thicknesses.
Sheet Titles & Columns:
- 0.7 nm - WO_x (V_D = -1 V): MoSe2 back gated device measurement (ID - VBG) using 0.7 nm WOx-adhered Rh contacts. With drain voltage -1 V and channel length 2 μm.
- Back gate bias: VG (V)
- Drain voltage normalized for width: ID (μA/μm)
- 1 nm - WO_x (V_D = -1 V): MoSe2 back gated device measurement (ID - VBG) using 1 nm WOx-adhered Rh contacts. With drain voltage -1 V and channel length 2 μm.
- Back gate bias: VG (V)
- Drain voltage normalized for width: ID (μA/μm)
- 0.5 nm - Ti (V_D = -1 V): MoSe2 back gated device measurement (ID - VBG) using 0.5 nm Ti-adhered Rh contacts. With drain voltage -1 V and channel length 2 μm.
- Back gate bias: VG (V)
- Drain voltage normalized for width: ID (μA/μm)
- 1 nm - Ti (V_D = -1 V): MoSe2 back gated device measurement (ID - VBG) using 1 nm Ti-adhered Rh contacts. With drain voltage -1 V and channel length 2 μm.
- Back gate bias: VG (V)
- Drain voltage normalized for width: ID (μA/μm)
- R - WO_x: calculated resistance of MoSe2 devices with varying WOx thicknesses.
- Thickness: nm
- Resistance: R (kΩ·μm)
- R - Ti: calculated resistance of MoSe2 devices with varying Ti thicknesses.
- Thickness: nm
- Resistance: R (kΩ·μm)
File: WOx_top_gate.xlsx
Description: Contains the ID-VTG measurements of a monolayer WSe2 top gate device with WOx - Rh contacts, at VD = -1 V. Also contains the ID - VD measurements of the same device with VG = -0.5 V, 0 V, and 0.5 V.
Sheet Titles & Columns:
- I_D - V_TG (V_D = -1 V): WSe2 top gate device measurement (ID-VTG) with WOx - Rh contacts at drain voltage of -1 V.
- Top gate bias : VTG (V)
- Drain voltage normalized for width and length: ID (W/L) (μA)
- I_D - V_D (V_G = -0.5 V): ID - VD measurements of WSe2 top gate device at gate bias of -0.5 V.
- Drain voltage: VDS (V)
- Drain voltage normalized for width and length: ID (W/L) (μA)
- I_D - V_D (V_G = 0 V): ID - VD measurements of WSe2 top gate device at gate bias of 0 V.
- Drain voltage: VDS (V)
- Drain voltage normalized for width and length: ID (W/L) (μA)
- I_D - V_D (V_G = 0.5 V): ID - VD measurements of WSe2 top gate device at gate bias of 0.5 V.
- Drain voltage: VDS (V)
- Drain voltage normalized for width and length: ID (W/L) (μA)
File: WSe2_Raman.xlsx
Description: Normalized Raman spectra of monolayer WSe2 before and after WOx evaporation.
Sheet Titles & Columns:
- Raman: Normalized Raman spectra of monolayer WSe2 before and after WOx evaporation.
- Raman shift (cm-1)
- Normalized Intensity on monolayer WSe2 flake
- Normalized Intensity on monolayer WSe2 flake after WOx evaporation
File: WSe2_TLM2.xlsx
Description: ID - VD measurements of WOx - Au contacts with varying channel lengths 0.59 μm, 0.5 μm, 0.35 μm, 0.31 μm, at gate biases VBG = -5 V, 0 V. Also contains the extracted resistance values of the varying gate biases.
Sheet Titles & Columns:
- TLM 2 - R vs L_ch (V_BG = 0V): extracted resistance values of the different channels lengths at gate bias 0 V.
- Channel length: Lchannel (μm)
- Resistance: R (Ω·μm)
- TLM 2 - R vs L_ch (V_BG = -5V): extracted resistance values of the different channels lengths at gate bias -5 V.
- Channel length: Lchannel (μm)
- Resistance: R (Ω·μm)
- TLM 2 - IDVD (V_BG = 0 V): ID - VD measurements of WOx - Au contacts with varying channel length 0.59 μm, 0.5 μm, 0.35 μm, 0.31 μm, with gate biases VBG = 0 V.
- Drain voltage: VD (V)
- Drain current: ID (μA/μm)
- TLM 2 - IDVD (V_BG = -5 V): ID - VD measurements of WOx - Au contacts with varying channel length 0.59 μm, 0.5 μm, 0.35 μm, 0.31 μm, with gate biases VBG = -5 V.
- Drain voltage: VD (V)
- Drain current: ID (μA/μm)
File: WSe2_TLM1.xlsx
Description: ID - VD measurements of WOx - Au contacts with varying channel length 1.01 μm, 0.88 μm, 0.61 μm, 0.50 μm, at gate biases VBG = -10 V, -5 V, 0 V. Also contains the extracted resistance values of the varying gate biases.
Sheet Titles & Columns:
- TLM 1 - R vs L_ch (V_BG = 0V): extracted resistance values of the different channels lengths at gate bias 0 V.
- Channel length: Lchannel (μm)
- Resistance: R (Ω·μm)
- TLM 1 - R vs L_ch (V_BG = -5V): extracted resistance values of the different channels lengths at gate bias -5 V.
- Channel length: Lchannel (μm)
- Resistance: R (Ω·μm)
- TLM 1 - R vs L_ch (V_BG = -10V): extracted resistance values of the different channels lengths at gate bias -10 V.
- Channel length: Lchannel (μm)
- Resistance: R (Ω·μm)
- TLM 1 - IDVD (V_BG = 0 V): ID - VD measurement of WOx - Au contacts with varying channel lengths 1.01 μm, 0.88 μm, 0.61 μm, 0.50 μm, with gate biases VBG = 0 V.
- Drain voltage: VD (V)
- Drain current: ID (μA/μm)
- TLM 1 - IDVD (V_BG = -5 V): ID - VD measurement of WOx - Au contacts with varying channel lengths 1.01 μm, 0.88 μm, 0.61 μm, 0.50 μm, with gate biases VBG = -5 V.
- Drain voltage: VD (V)
- Drain current: ID (μA/μm)
- TLM 1 - IDVD (V_BG = -10 V): ID - VD measurement of WOx - Au contacts with varying channel lengths 1.01 μm, 0.88 μm, 0.61 μm, 0.50 μm, with gate biases VBG = -10 V.
- Drain voltage: VD (V)
- Drain current: ID (μA/μm)
File: WSe2_IDVG_and_R.xlsx
Description: Contains ID - VBG measurements on monolayer WSe2 using WOx - Rh and Ti - Rh contacts. With VD = -1 V, and Lch = 2 μm. Also contains the calculated resistance of WSe2 devices as a function of the WOx and Ti thicknesses.
Sheet Titles & Columns:
- 1.5 nm - WO_x (V_D = -1 V): ID - VBG measurements on monolayer WSe2 using 1.5 nm WOx - Rh contacts.
- Back gate voltage: VG
- Drain current: ID (μA/μm)
- 3 nm - WO_x (V_D = -1 V): ID - VBG measurements on monolayer WSe2 using 3 nm WOx - Rh contacts.
- Back gate voltage: VG
- Drain current: ID (μA/μm)
- 0.5 nm - Ti (V_D = -1 V): ID - VBG measurements on monolayer WSe2 using 0.5 nm Ti - Rh contacts.
- Back gate voltage: VG
- Drain current: ID (μA/μm)
- 4 nm - Ti (V_D = -1 V): ID - VBG measurements on monolayer WSe2 using 4 nm Ti - Rh contacts.
- Back gate voltage: VG
- Drain current: ID (μA/μm)
- R - WO_x: calculated resistance of WSe2 devices as a function of the WOx thicknesses.
- Thickness: nm
- Resistance: R (Ω·μm)
- R - Ti: calculated resistance of WSe2 devices as a function of the Ti thicknesses.
- Thickness: nm
- Resistance: R (Ω·μm)
File: WSe2_AFM_measurements.xlsx
Description: Contains the normalized adhesion forces on WSe2 and SiO2 surfaces using WOx- and Ti-coated AFM tips for the measurements. Also contains a representative force vs. displacement curve using the WOx coated tip on WSe2.
Sheet Titles & Columns:
- Adhesion on WSe2: normalized adhesion forces on WSe2 using WOx- and Ti-coated AFM tips for the measurements.
- WOX coated AFM tip adhesion force: nN/nm2
- Ti coated AFM tip adhesion force: nN/nm2
- Adhesion on SiO2: normalized adhesion forces on SiO2 using WOx- and Ti-coated AFM tips for the measurements.
- WOX coated AFM tip adhesion force: nN/nm2
- Ti coated AFM tip adhesion force: nN/nm2
- Force vs. displacement: representative force vs. displacement curve using the WOx coated tip on WSe2.
- Displacement: nm
- Trace curve - Force: nN
- Displacement: nm
- Retrace curve - Force: nN
File: Energy_Band_on_WSe2_WOx_and_Ti.xlsx
Description: Energy band structure of WSe2 / WO3 / metal and WSe2 / Ti / metal stacks.
Sheet Titles & Columns:
- WOx_adhesion_layer_on_WSe2: Energy band structure of WSe2 / WO3 / metal stack.
- Displacement - Ec (nm): conduction band displacement
- Ec - Energy (eV): conduction band energy
- Displacement (nm): valance band displacement
- Ev - Energy (eV): valence band energy
- Displacement - EF (nm): fermi level displacement
- EF - Energy (eV): Fermi level energy
- Ti_adhesion_layer_on_WSe2: Energy band structure of WSe2 / Ti / metal stack.
- Displacement - Ec (nm): conduction band displacement
- Ec - Energy (eV): conduction band energy
- Displacement (nm): valance band displacement
- Ev - Energy (eV): valence band energy
- Displacement - EF (nm): fermi level displacement
- EF - Energy (eV): Fermi level energy
File: XPS_WSe2_WOx_stack.xlsx
Description: XPS spectra of bulk WSe2 and evaporated 1 nm WOx on p++ Si substrate. Contains the W 4f and Se 3d spectra of the WSe2 - WOx stack.
Sheet Titles & Columns:
- W4f spectrum of WSe2 WOx stack: W 4f spectrum of the WSe2 - WOx stack.
- Binding Energy (eV)
- CPS: counts per second
- WSe2 4f7/2 (Counts)
- WSe2 4f5/2 (Counts)
- WO3 4f7/2 (Counts)
- WO3 4f5/2 (Counts)
- Background (Counts)
- Envelope (Counts)
- Se3d spectrum of WSe2 WOx stack: Se 3d spectrum of the WSe2 - WOx stack.
- Binding Energy (eV)
- CPS: counts per second
- WSe2 3d5/2 (Counts)
- WSe2 3d3/2 (Counts)
- Background (Counts)
- Envelope(Counts)
File: XPS_evaporated_Ti_WOx.xlsx
Description: XPS spectra of evaporated 3 nm WOx and 3 nm Ti on p++ Si substrates. W 4f and Valence band edge spectra of WOx and Ti 2p and Valence band edge spectra of Ti.
Sheet Titles & Columns:
- Valence band edge of 3 nm WOx: Valence band edge spectra of WOx
- Binding Energy (eV)
- Counts
- Valence band edge of 3 nm Ti: Valence band edge spectra of Ti
- Binding Energy (eV)
- Counts
- W 4f spectrum of WOx: W 4f spectrum of WOx
- Binding Energy (eV)
- CPS: counts per second
- WO3 4f7/2 (Counts)
- WO3 4f5/2 (Counts)
- WO3 5p3/2 (Counts)
- Background (Counts)
- Envelope (Counts)
- W 4f spectrum of WOx: Ti 2p spectrum of Ti.
- Binding Energy (eV)
- CPS: counts per second
- Ti 2p3/2 (Counts)
- Ti 2p1/2 (Counts)
- TiO2 2p3/2 (Counts)
- TiO2 2p1/2(Counts)
- Ti (II) 2p3/2 (Counts)
- Ti (II) 2p1/2 (Counts)
- Ti (III) 2p3/2 (Counts)
- Ti (III) 2p1/2 (Counts)
- Background (Counts)
- Envelope (Counts)