SILICON ON INSULATOR TECHNOLOGY

SILICON ON INSULATOR(SOI)

SOI is a technology used for providing isolated substrates for manufacturing BICMOS.
In this 3 methods are there

1.Dielectric Isolation

2.wafer bonding method

3.smart cut process

SOI technology advantages

• Reduction of junction depth
• low leakage current
• Better high speed characteristics (capacitance)
• No highly doped layer beneath the device
• lower gds conductance at high frequency
• Better Soft Error Rate at small dimension
• Latch-up immunity due to BOX
• Better integration density
• Low voltage thanks to dynamic threshold voltage
• Low power (P = C.V².f +Ileak.V)
• High resistivity substrate availability
• Less substrate loss
• Reduction of cross-talk through substrate in mixed ICs
• High quality factor for passives

SOI technology drawbacks

• Kink effect
• Parasitic bipolar transistor
• gds increase
• Self heating effect due to low thermal conductivity of BOX
• mobility degradation drain current diminution