Seminar On Bicmos Technology Submitted To Submitted By

Seminar On Bicmos Technology Submitted To: Submitted By: www. mobikida. wordpress. com Laxman Ghaytadak Satish

CONTENTS § § § § Introduction Abstract Characteristics of CMOS Technology Characteristics of Bipolar Technology Combine advantages in Bi. CMOS Technology Bi. CMOS Fabrication Bi. CMOS Integrated Circuits Advantages of Bi. CMOS Disadvantages of Bi. CMOS Applications of Bi. CMOS Comparison between CMOS and Bi. CMOS Products Conclusion Literature Survey

INTRODUCTION �The history of semiconductor devices started in 1930’s when Lienfed and Heil first proposed the mosfet. �Bipolar Technology was started in 1980’s. �CMOS Technology was also started in mid 1980’s. �Later in 1990 there was a cross over between bipolar and CMOS Technology. �In Bi. CMOS technology, both the MOS and bipolar device are fabricated on the same chip.

�The objective of the Bi. CMOS is to combine bipolar and CMOS so as to exploit the advantages of both the technlogies. �Today Bi. CMOS has become one of the dominant technologies used for high speed, low power and highly functional VLSI circuits. �The process step required for both CMOS and bipolar are similar so the Bi. CMOS process has been enhanced and integrated into the CMOS process without any additional steps.

�The primary approach to realize high performance Bi. CMOS devices is the addition of bipolar process steps to a baseline CMOS process. �The Bi. CMOS gates could be used as an effective way of speeding up the VLSI circuits. �The applications of Bi. CMOS are vast. �Advantages of bipolar and CMOS circuits can be retained in Bi. CMOS chips. �Bi. CMOS technology enables high performance integrated circuits IC’s but increases process complexity.

ABSTRACT �Bi. CMOS technology is a combination of Bipolar and CMOS technology. �CMOS technology offers less power dissipation, smaller noise margins, and higher packing density. �Bipolar technology, on the other hand, ensures high switching and I/O speed and good noise performance �Now we are in 3 rd Generation Bi. CMOS Technology.

�Bi. CMOS technology accomplishes both - improved speed over CMOS and lower power dissipation than bipolar technology. �The main drawback of Bi. CMOS technology is the higher costs due to the added process complexity. �This greater process complexity in Bi. CMOS results in a cost increase compared to conventional CMOS technology.

Characteristics of CMOS Technology � Lower static power dissipation � Higher noise margins � Higher packing density � High yield with large integrated complex functions � High input impedance (low drive current) � Scaleable threshold voltage � High delay load sensitivity � Low output drive current (issue when driving large capacitive loads) � Low transconductance, where transconductance, gm Vin � Bi-directional capability (drain & source are interchangeable) � A near ideal switching device � Low gain

Characteristics of Bipolar Technology � Higher switching speed � Higher current drive per unit area, higher gain � Generally better noise performance and better high frequency characteristics � Improved I/O speed (particularly significant with the growing importance of package limitations in high speed systems). � high power dissipation � lower input impedance (high drive current) � low packing density � low delay sensitivity to load � High transconductance gm (gm Vin) � It is essentially unidirectional.

Combine advantages in Bi. CMOS Technology �It follows that Bi. CMOS technology goes some way towards combining the virtues of both CMOS and Bipolar technologies �Improved speed over purely-CMOS technology �Lower power dissipation than purely-bipolar technology(Lower power consumption than bipolar) �Flexible I/Os for high performance �Improved current drive over CMOS �Improved packing density over bipolar �High input impedance �Low output impedance �High Gain and low noise

Bi. CMOS FABRICATION

Bi. CMOS Integrated Circuits

ADVANTAGES �Improved speed over CMOS �Improved current drive over CMOS �Improved packing density over bipolar �Lower power consumption than bipolar �High input impedance �Low output impedance �High Gain and low noise

DISADVANTAGES �Increased manufacturing process complexity �higher cost �Speed degradation due to scaling �longer fabrication cycle time Bi. CMOS process �Bipolar process + Well + Gate Oxide & Poly + CMOS process

APPLICATIONS OF BICMOS �Full custom ICs �ALU’s, Barrel Shifters �SRAM, DRAM �Microproessor, Controller �Semi custom ICs �Register, Flipflop , Standard cells �Adders, mixers, ADC, DAC �Gate arrays �Flash A/D Coverters

COMPARISON between BASIC CMOS & Bi. CMOS 1. Speed Comparison 3. Area Comparison 2. Delay Comparison

REFERENCES �www. google. com �www. wikipedia. org

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