**1. Introduction**

An atomical graphene layer, which was invented in 2004 [1, 2], is considered as one of the best candidates for a broad application range with novel electronic and optoelectronic behaviors [1–21]. Unfortunately, the conductive graphene with no bandgap prevented its outstanding physical and chemical potentials. Thus, its bandgap tuning via various approaches is highly desired for extreme performance devices (**Figure 1**).

Recently, etching technologies are emerging as one of the best efficient tools to tune a device's performance, thereby extending to many different fields in broadband [20–30]. The new approaches include the following: (i) inductively coupled plasma (ICP), neutral beam-based atomic layer etching (ALE), ion beam and reactive ion etching (RIE) [22–29], (ii) chemical vapor deposition (CVD) [30, 31] and (iii) thermally activated nanoparticles [32]. Plasma has used Si-integrated circuits for etching [22]. Among breakthroughs, plasma etching represents an important role in Si and non-Si (metal)-assisted devices. This chapter will present recent advances in new graphene etch technologies and their related applications.

**Figure 1.**

*Etch processing of graphene few-layer or graphene nanoribbon on various substrates through plasma, physic, chemistry to tune its electronics and optoelectronics.*
