In this paper we report on the characterization of the Hamamatsu VUV4 (S/N: S13370-6152) Vacuum Ultra-Violet (VUV) sensitive Silicon Photo-Multipliers (SiPMs) as part of the development of a solution for the detection of liquid xenon scintillation light for the nEXO experiment. Various SiPM features, such as: dark noise, gain, correlated avalanches, direct crosstalk and Photon Detection Efficiency (PDE) were measured in a dedicated setup at TRIUMF. SiPMs were characterized in the range $163 text{ } text{K} leq text{T}leq 233 text{ } text{K}$. At an over voltage of $3.1pm0.2$ V and at $text{T}=163 text{ }text{K}$ we report a number of Correlated Avalanches (CAs) per pulse in the $1 upmutext{s}$ interval following the trigger pulse of $0.161pm0.005$. At the same settings the Dark-Noise (DN) rate is $0.137pm0.002 text{ Hz/mm}^{2}$. Both the number of CAs and the DN rate are within nEXO specifications. The PDE of the Hamamatsu VUV4 was measured for two different devices at $text{T}=233 text{ }text{K}$ for a mean wavelength of $189pm7text{ nm}$. At $3.6pm0.2$ V and $3.5pm0.2$ V of over voltage we report a PDE of $13.4pm2.6text{ }%$ and $11pm2%$, corresponding to a saturation PDE of $14.8pm2.8text{ }%$ and $12.2pm2.3%$, respectively. Both values are well below the $24text{ }%$ saturation PDE advertised by Hamamatsu. More generally, the second device tested at $3.5pm0.2$ V of over voltage is below the nEXO PDE requirement. The first one instead yields a PDE that is marginally close to meeting the nEXO specifications. This suggests that with modest improvements the Hamamatsu VUV4 MPPCs could be considered as an alternative to the FBK-LF SiPMs for the final design of the nEXO detector.
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