Feng Ying, Chen Ke
Nanotechnology. 2015 Jan 21;26(3):035302. doi: 10.1088/0957-4484/26/3/035302. Epub 2014 Dec 30.
We report a dry transfer method that can tranfer chemical vapor deposition (CVD) grown graphene onto liquid-sensitive surfaces. The graphene grown on copper (Cu) foil substrate was first transferred onto a freestanding 4 μm thick sputtered Cu film using the conventional wet transfer process, followed by a dry transfer process onto the target surface using a polydimethylsiloxane stamp. The dry-transferred graphene has similar properties to traditional wet-transferred graphene, characterized by scanning electron microscopy, atomic force microscopy, Raman spectroscopy, and electrical transport measurements. It has a sheet resistance of 1.6 ∼ 3.4 kΩ/□, hole density of (4.1 ∼ 5.3) × 10(12) cm(-2), and hole mobility of 460 ∼ 760 cm(2) V(-1) s(-1) without doping at room temperature. The results suggest that large-scale CVD-grown graphene can be transferred with good quality and without contaminating the target surface by any liquid. Mg/MgO/graphene tunnel junctions were fabricated using this transfer method. The junctions show good tunneling characteristics, which demonstrates the transfer technique can also be used to fabricate graphene devices on liquid-sensitive surfaces.
我们报道了一种干式转移方法，该方法能够将化学气相沉积（CVD）生长的石墨烯转移到对液体敏感的表面上。首先，使用传统的湿式转移工艺，将生长在铜（Cu）箔衬底上的石墨烯转移到一个独立的4μm厚的溅射铜膜上，然后使用聚二甲基硅氧烷印章通过干式转移工艺将其转移到目标表面。通过扫描电子显微镜、原子力显微镜、拉曼光谱和电输运测量对干式转移的石墨烯进行表征，结果表明其具有与传统湿式转移石墨烯相似的性质。在室温下未掺杂时，其方块电阻为1.6 ∼ 3.4 kΩ/□，空穴密度为(4.1 ∼ 5.3)×10(12) cm(-2)，空穴迁移率为460 ∼ 760 cm(2) V(-1) s(-1)。结果表明，大规模CVD生长的石墨烯能够以高质量进行转移，且不会被任何液体污染目标表面。利用这种转移方法制备了Mg/MgO/石墨烯隧道结。这些结表现出良好的隧穿特性，这表明该转移技术也可用于在对液体敏感的表面上制备石墨烯器件。
