**3. Conductive Ag-glass composite powder**

Ag has very high conductivity, and thus, it has been used as an electrode for solar cells and various electric circuits [18–20].

The electrode layer formed is mixed with glass frit and an inorganic binder in addition to the conductive powder and organic binder to form a paste through heat treatment after printing. The glass frit plays an important role when sintering power by acting as a pool of liquid sintering agent, as well as in densification by helping to form an electrode layer without pores between the powders. Since a small amount (The mixing ratio of the conductive powder of the electrode and the glass frit is generally at least 8–20 times different) is added compared to the conductive powder, it is very difficult to evenly disperse it throughout. In addition, when a large amount is added to evenly disperse the entire electrode layer, the content of the conductive powder must be relatively low due to the density of the paste, which causes a problem of lowering the conductivity. In order to overcome this problem, the electrode powder synthesis technology in which glass and Ag powder are composited into a core-shell

**Figure 1.**

*Formation mechanism of silver-glass composite powder [21].*
