<P><B>Abstract</B></P> <P>We report on the fabrication and transport characteristics of van der Waals (vdW)-contacted planar Josephson junctions. In a device, two pieces of cleaved 2H-NbSe<SUB>2</SUB> superconducting flakes and a monolayer graphene sheet serve as the superconducting electrodes and the normal-conducting spacer, respectively. A stack of NbSe<SUB>2</SUB>−graphene−hexagonal-boron-nitride (hBN) heterostructure with clean and flat interfaces was prepared by a dry transfer technique. The outermost hBN layer protected the NbSe<SUB>2</SUB>−graphene−NbSe<SUB>2</SUB> Josephson junction from chemical contamination during the fabrication processes. The Josephson coupling was confirmed by a periodic modulation of the junction critical current <SUB> I c </SUB> in a perpendicular magnetic field. The temperature dependence of <SUB> I c </SUB> showed long and diffusive Josephson coupling characteristics. The temperature dependence of the superconducting gap, obtained from the multiple Andreev reflection features, followed the Bardeen−Cooper−Schrieffer (BCS) prediction.</P>
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