**3.2 MEMS technology process**

**Bulk micromachining** produces mechanical structures in the silicon substrate by using etching masks. Bulk micro-machined module is shown in **Figure 8**.

**Surface Micromachining** produce mechanical structures above the substrate surface by using sacrificial layer. Surface micro-machined module is presented in **Figure 9**. In Bulk micromachining technology silicon is machined using etching processes. Surface micromachining uses layers deposition on the substrate to produce a structural layer.

**Figure 8.** *MEMS bulk micromachining technology.*

*MEMS surface micromachining technology.*

Surface micromachining process does not depend on the substrate used. It can be part of other production processes that modify the substrate. For example, fabrication of MEMS on a substrate with embedded control devices, in which MEMS process is integrated with integrated circuit technology.

**13**

*Introductory Chapter: Ultra-Wideband Technologies DOI: http://dx.doi.org/10.5772/intechopen.97675*

• MEMS Switching matrix with low loss

• MEMS 90GHz Detection Arrays

low-cost and small volume.

filters, antennas, and phase shifters.

light such as optical reflectors and switches.

**3.3 MEMS components**

**Figure 11.**

*MEMS bolometer coupled antenna array.*

This process is used to manufacture a wide spectrum of MEMS modules for several applications. Bulk micromachining is a subtractive fabrication process, that converts the substrate, into the mechanical parts of the MEMS module. MEMS modules can be designed by using electromagnetic software such as ADS, HFSS, and CST. The design outcomes layers masks, layout that are used to produce the MEMS module. MEMS production process is shown in **Figure 10**. In **Figure 11** the block diagram of a MEMS bolometer coupled antenna array is presented. Packaging of MEMS modules may be more complicated. However, higher devices are easier to produce when compared to surface micromachining. Applications of RF MEMS technology:

• Tunable microwave MEMS passive elements such as inductors and filters

MEMS components are categorized in one of several applications. Such as:

1.**MEMS The goal of MEMS sensors** is to sense changes and interact with the environments. MEMS sensors include sensors that detect change in temperature, sensors that detect chemical changes, movement sensors, optical sensors, radiation sensors and inertia sensors. MEMS sensors are useful due to their

2.**Microwave MEMS** are modules used to transmit microwave signals, to switch or to filter RF signals. **Microwave MEMS** include tunable capacitors, switches,

3.**Optical MEMS** are compact modules that amplify, direct, reflect, and filter

4.Thermal or electrostatic actuators provide power to other components or devices.

5.**Biological MEMS** are modules that, interact with biological tissue. These modules interact with biological cells, medical reagents, proteins, and other

• MEMS antenna arrays coupled to bolometer for detection arrays

*Introductory Chapter: Ultra-Wideband Technologies DOI: http://dx.doi.org/10.5772/intechopen.97675*

**Figure 11.** *MEMS bolometer coupled antenna array.*

This process is used to manufacture a wide spectrum of MEMS modules for several applications. Bulk micromachining is a subtractive fabrication process, that converts the substrate, into the mechanical parts of the MEMS module. MEMS modules can be designed by using electromagnetic software such as ADS, HFSS, and CST. The design outcomes layers masks, layout that are used to produce the MEMS module. MEMS production process is shown in **Figure 10**. In **Figure 11** the block diagram of a MEMS bolometer coupled antenna array is presented. Packaging of MEMS modules may be more complicated. However, higher devices are easier to produce when compared to surface micromachining. Applications of RF MEMS technology:

