Section 2 Liquid Metals

*Liquid Metals*

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**30**

**Chapter 4**

Metals

**Abstract**

parameters

**33**

**1. Introduction**

ceramic interface [11].

*Hadef Zakaria and Kamli Kenza*

the electric properties of combination.

Adhesion Phenomenon of Liquid

In this chapter, we study an interfacial phenomenon between liquid metals and ceramic substrates. Therefore, investigation of these phenomena is of great importance not only in technological applications but also in fundamental understanding of physical behavior of the adhesion between two different materials as far as their electrical structures and physiochemical properties are concerned. Moreover, adhesion energy is interpreted thermodynamically by the interfacial interactions and the nature of bonding between liquid metal and ceramic material. The adhesion energy in metal/ceramic systems is determined by using an electro-acoustical model based on the propagation of the acoustic wave in the interface and strongly depends on

**Keywords:** Liquid metal, Ceramics, Adhesion, Interfaces, Gap energy, Acoustic

Metalized ceramics by liquid metal have a crucial uses in several modern technological applications such as solar cell [1–4] electrical devices [5–7] and Micro Electro Mechanical Systems (MEMS) [8–10]. Recently, these systems are used as the conductive wiring of microelectronic circuits; there has been considerable interest in the characterization of the structure and properties of liquid metal/

However, the coating of ceramic surfaces can affect most of the properties of the interface. Therefore, the investigation of interfacial phenomena between metals and ceramic substrates is of great importance not only in technological applications but also in fundamental understanding of physical behavior of the adhesion between two different materials as far as their electrical structures and physiochemical properties are concerned. In fact, at the interface of a metal/ceramic system, adhesion occurs when the atoms or molecules of the two contacting surfaces approach each other so closely that attractive forces between approaching atoms (or molecules) bond them together. The strength of the bond depends on the size of the atoms, the distance between them, and the presence or absence of contaminant matter on the surface [1]. Hence, the strength or wea1kness of bonds is the key factor to determine the interface stability: good adhesion, welded adhesion, perfect bonding, weak bonding smooth interface, etc. The metal/ceramic contact is characterized by the adhesion energy, *Wad*, which is the work per unit area of the interface needed to separate reversibly a metal/ceramic interface [2]. This physicochemical

#### **Chapter 4**
