History of IC:
1947 :transistor was invented and demonstrated @bell labs
1958: crude IC (basic form of an integrated circuit (IC) before it’s fully developed or refined.
It might not have all the features or sophistication of a more advanced IC.) Ge @Texas Instrument.
1961: 1st sillicon IC in market @fairchild semiconductor
made of 2 transistor ,register, interconnect
VLSI (very large scale integration):
all about integration
due to advancement of sillicon technology now on the same amount of silicon 10-1000million transistor, 1/2 to ~30 miles
of interconnect
1000 times faster operation
cost few dollar
Advantage of VLSI:
less area
less power consumption
Less testing
Higher reliability because due to improved on chip interconnects
Higher speed because reduce interconnect length
Significant cost saving
Moore’s Law:
In 1965: Gordon Moore stated that silicon technology will the no of transistor on a chip every year.
Later updated in 1975: no of transistor double after every two year.
Microprocessor technology: it developed after Ic
Microprocessor=IC tech+Software
IC Technology
Semicondutor Wafer: circular in nature made of semiconductor material
size of wafer: 12inches (like a dinner plate size( only for remember purpose)).
Small piece of wafer is called Die
Multiple Die coming out of wafer.
Classification of IC technology:
You can classify based on two ways
- Based on no of devices used(FET)
- Based on feature size of the process
Based on no of devices used(FET):
SSI(Small scale integration):
1 to 100 transistor used and develpoed in 1960
use of making gates ,op-amp, linear ckt etc.
MSI(Medium scale integration):
100 to 1000 transistor used and develpoed in 1965
use of making registor, filter etc.
LSI(Large scale integration):
1000 to 10000 transistor used and develpoed in 1970
use of making microprocessor, Analog to digital converter(A/D) etc.
VLSI(Very Large scale integration):
10000 to 100000 transistor develpoed in 1975
use of making memory,computer, DSP etc..
VVLSI(Very Very Large scale integration):
Billion of transistor used and develpoed in 1975
use of making SOC(System on chip)
Dennard Scaling:
Under the constant electric field predicts an increase in speed & low power consumption of digital Mos ckt. when critical dimension are scaled down in 1974
Critical dimension: length , width and thickness of oxide
Goal of the IC designer:
Meet the mareket requirements:
Satisfying the customer needs
Beating the competition ( increasing performance or functionality of the product
and reducing cost compared to the avialable solution)
Achieved by using next generation silicon technology
new design concept + tools
high level of integeration
Design Approach:
- full custom: full control of design ,it best but takes more time
- Semi Custom: based on standard cell( use cell libraries from vendor), faster design time
- EPLA/EPLD: FPGA
electrically programmable , very flexible ,fastest design time
