Interlayers silicon nitride

Stoichiometric and hydrogenated amorphous silicon nitrides (Si3N4, and a-SiNx H, respectively) have many uses in the microelectronics industry, such as to passivate various capless devices and to act as a diffusion barrier against species such as H2O or Na+. Silicon nitride is also employed as a diffusion barrier in selective silicon oxidation (because of the low oxidation rate) and as an interlayer insulator material [2]. 

Density of Cubic Boron Nitride. The c-BN structure, with its tetrahedral bonding, is isotropic and, except on the (111) plane, is more compact than that of h-BN (with its sjp anisotropic structure and wide interlayer spacing). Consequently c>BN has higher theoretical density than h-BN (3.43 g/cm vs. 2.34 g/cm ). It should be pointed out that the diamond-like structure of cubic boron nitride is similar to those of the other two refiactory covalent nitrides, i.e., aluminum nitride and silicon nitride, as weU as silicon carbide (see Ch. 7, Sec. 3.0). 

Singh, M., Martinez Fernandez, J., Asthana, R., Rico, J. R. (2012). Interfacial characterization of silicon nitride/silicon nitride joints brazed using Cu-base active metal interlayers. Ceramics International, 38, 2793-2802. doi 10.1016/j. ceramint.2011.11.050. 

Finally, we will consider PECVD silicon oxynitrides, and their unique characteristics. When oxygen is added to a PECVD nitride film, there are indications that it may improve its crack resistance as a final passivation layer.13 Also, there may be advantages in terms of its electrical characteristics as an interlayer dielectric. Therefore, the nature of films grown when N20 is added to a SiH4, NH3 and He gas mixture in a high frequency (13.56 MHz), cold-wall, parallel-plate reactor have been studied. 

Multi-chip modules, in which chips are attached with TAB directly to an interconnection substrate, typically silicon or aluminum nitride or other ceramics, represent an emerging technology. The module interconnect circuits are generated with IC fabrication technology, but at a relatively modest level of resolution. Typically, as shown in Figure 6, the substrates can include power and ground planes plus one or more signal planes, and low dielectric constant interlayer materials such as polyimides. These modules, which have feature sizes ca. 5 to 50 pm, and which are mounted directly on the PC board or serve as the board itself,... 

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