INTEGRATED CIRCUITS

• An Integrated Circuit is complete electronic circuit in which both the active & passive components are fabricated on a tiny single chip of SILICON
• Active components are those components which are able to produce gain.
• Passive components are those components which do not have this ability.
• Tremendous changes in Electronic circuitry starts after the invention of Triode by L.D Forest in 1907.
• Invention of Transistor in 1948 by W.H Bardeen & I.Bardeen electronic circuit became reduced in size.
• In early 1960 field of microelectronic born to meet the requirement of Military.
• SSI- small scale integration
• LSI - large scale integration
• MSI - medium scale integration
• VLSI - very large scale integration
• ULSI - ultra large scale integration
• GSI - giga scale integration
• An Integrated Circuit is complete electronic circuit in which both the active & passive components are fabricated on a tiny single chip of SILICON
• CLASSIFICATION OF INTEGRATED CIRCUITS

  • ON STRUCTURE BASIS
  • ON FUNCTION BASIS
• ON STRUCTURE BASIS

  • MONOLITHIC INTEGRATED CIRCUITS
  • HYBRID/MULTICHIP INTEGRATED CIRCUITS
  • THICK & THIN FILM INTEGRATED CIRCUITS
• MONOLITHIC IC

  The word monolithic means "SINGLE STONE" or more appropriately "Single solid structure'.

  In this all circuit all components are fabricated within single continuous piece of silicon crystalline material called “WAFER” or "SUBSTRATE"
• ADVANTAGES & DISADVANTAGES OF MONOLITHIC IC's

  
  

  These have advantage of lower cost and high reliability.

  
  

  However they have poor isolation between the components, short range of passive components, no flexibility of circuit design.

  
  

  INDUCTORS cannot be fabricated
• THICK & THIN FILM IC

  
  

  The difference between between thick & thin film are not their relative thickness but method of depositing film.

  These IC's are not formed within single silicon wafer but surface of an insulating substrate such as glass or ceramic materials.

  Only passive components are formed through thick or thin film.
• THIN FILM IC

  
  

  Such circuits are constructed by depositing film of conducting material through a mask on the surface of substrate made of glass or ceramic.

  
  

  Following methods are used to produce thin film.

  
  

  VACUUM EVAPORATION CATHODE SPUTTERING
• THICK FILM IC

  
  

  These are printed thin film circuits.

  
  

  Silk screen printing techniques are employed to create the desired circuit pattern on the surface of substrate
• ADVANTAGES & DISADVANTAGES OF FILM IC's

  These have advantages of forming passive components of broader range.

  
  

  High tolerance

  
  

  Isolation is better

  
  

  Better high frequency performance

  
  

  Not able to fabricate active components Comparatively higher cost

  
  

  Larger physical size
• HYBRID IC

  
  

  These IC's are formed either by interconnecting a number of individual chips or by combination of film & monolithic ICs

  
  

  They have chief advantage high flexibility but too much expensive for mass production and least reliability.
• ON FUNCTION BASIS

  LINEAR

  DIGITAL
• LINEAR IC's (LICs)

  • These also referred as "Analog IC".
  • They possess much high reliability
  • Their use is much less as compared to digital and mostly used in military and industrial application
• USE OF LIC's

  • Operational amp.
  • Power amp.
  • Microwave amp.
  • Voltage comparators
  • Small - signal amp.
  • RF & IF amp.
  • Multipliers
  • Voltage regulators
• DIGITAL IC's

  • About 80% of IC market has been captured by digital IC which is mostly used in computer IC
  • Digital IC contain circuits whose input and output voltages are limited to 2 possible level - high and low
• USES OF DIGITAL IC's

  • Digital circuits
  • Flip-flops
  • Counters
  • Clock chips
  • Calculator chips
  • Memory chips
  • Microprocessors
• ADVANTAGES OF IC's

  • Extremely small physical size
  • Very small weight
  • Reduced cost
  • Extremely high reliability
  • Increased response time & speed
  • Low power consumption
  • Easy replacement
  • Higher yield
• DRAWBACK OF IC's

  • Coils & inductors cannot be fabricated
  • IC's function are fairly low voltage
  • They handle only limited amount of power
  • They are quite delicate and cannot withstand rough handling or excessive heat