Ultrafast Growth of Large‐Area Uniform, Millimeter‐Size MoSe₂ Single Crystals on Low‐Cost Soda‐Lime Glass

Abstract

2D semiconducting transition metal dichalcogenides (TMDCs) have emerged as essential building blocks for engineering next‐generation integrated electronics. To achieve this, the controllable synthesis of monolayer TMDCs with high crystal quality, low cost, and high yield is crucial, while it remains challenging. Herein, the direct synthesis of large‐area uniform, millimeter‐size monolayer MoSe2 single crystals on a 6‐centimeter‐long soda‐lime glass template, by using a designed “beam‐bridge” assisted metal oxide precursor feeding strategy via chemical vapor deposition (CVD), is reported. Notably, several tenths of millimeter‐scale, triangular‐shaped monolayer MoSe2 single crystals are obtained in one batch within 25 s’ growth, affording so far the fastest growth rate (≈50 µm s−1). This ultrafast growth behavior is proposed to be mediated by the sufficient, homogeneous release of Mo‐based precursor, the catalytic property of sodium atoms on soda‐lime glass substrate, as well as the improved surface kinetics on the molten glass surface. Moreover, the thickness‐controlled growth from monolayer to bilayers is also realized. This work provides brand new insights for the batch production of large single‐crystal TMDCs, which should propel its practical applications in versatile fields.

Chemical Vapor Deposition of Uniform and Large-Domain Molybdenum Disulfide Crystals on Glass/Al2O3 Substrates

“…The MoS 2 domains exhibited triangle shapes and demonstrated lateral sizes larger than 400 μm, which is comparable to the MoS 2 domain sizes on glass substrates reported in other works [ 12 , 26 ]. The large crystal size could be attributed to the smooth, molten surface together with the catalytic role of the glass substrates, as reported in previous works [ 12 , 26 , 27 , 35 , 36 ]. As shown in Figure 3 b, numerous tiny islands could be observed on the large MoS 2 triangle domains after additional magnification.…”

“…Therefore, as shown in Figure 5 c,d, the Al 2 O 3 buffer layer would not affect the Mo-source supply during the process of MoS 2 growth and MoS 2 crystals with uniform thickness were grown. Furthermore, as discussed in previous works [ 12 , 26 , 27 , 35 , 36 ], the large domain size of MoS 2 at the center region of glass substrates could be ascribed to the smooth, molten glass surface under high temperature, together with the catalytic role of Na in the glass substrates, which reduce the energy barrier in the CVD process.…”

Wafer-Scale Uniform Synthesis of 2D Transition Metal Dichalcogenides Single Crystals via Chemical Vapor Deposition

“…Very recently, our group realized the large-area growth of uniformly distributed, millimeter-scale monolayer MoSe 2 single crystals on 6 cm long molten-soda-lime glass substrates, by designing a "beam-bridge" assisted metal oxide precursor feeding strategy (Figure 4a). 37 Dozens of discrete MoSe 2 flakes even visible to the naked eye were obtained on soda-lime glass after a very short growth time of ∼25 s (Figure 4b). The millimeter-sized, triangular-shaped MoSe 2 single crystals uniformly distributed on molten glass with a size of 6.0 × 3.5 cm 2 (Figure 4c−e), which was ascribed to the specially designed "beam-bridge" like a metal-precursor-container positioned between metal precursor and substrate.…”

NaCl-Assisted Chemical Vapor Deposition of Large-Domain Bilayer MoS2 on Soda-Lime Glass

“…Wang et al successfully prepared MoS 2 crystals by CVD using sulfur (S) powder and molybdenum trioxide (MoO 3 ) as precursors and SiO 2 /Si as a growth substrate [ 20 ], with the size reaching micrometers [ 21 , 22 , 23 , 24 ]. So far, the domain size of monolayer MoS 2 crystal growth based on CVD has reached the millimeter level [ 25 , 26 ].…”