1. EE 5340 Semiconductor Device Theory Lecture 7 - Fall 2010
Professor Ronald L. Carter

2. Second Assignment
Please print and bring to class a signed copy of the document appearing at
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3. Silicon Planar Process1
M&K1 Fig. 2.1 Basic fabrication steps in the silicon planar process:
(a) oxide formation,
(b) oxide removal,
(c) deposition of dopant atoms,
(d) diffusion of dopant atoms into exposed regions of silicon.
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4. LOCOS Process1
1Fig 2.26 LOCal Oxidation of Silicon (LOCOS). (a) Defined pattern consisting of stress-relief oxide and Si3N4 where further oxidation is not desired, (b) thick oxide layer grown over the bare silicon region, (c) stress-relief oxide and Si3N4 removed by etching, (d) scanning electron micrograph (5000 X) showing LOCOS-processed wafer at (b).
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5. Al Interconnects1
1Figure (p. 104) A thin layer of aluminum can be used to connect various doped regions of a semiconductor device. 1
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6. Ion Implantation1
1Figure (p. 80) In ion implantation, a beam of high-energy ions strikes selected regions of the semiconductor surface, penetrating into these exposed regions.
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7. Phosphorous implant Range (M&K1 Figure 2
Phosphorous implant Range (M&K1 Figure 2.17) Projected range Rp and its standard devia-tion DRp for implantation of phosphorus into Si, SiO2, Si3N4, and Al [M&K ref 11].
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8. Implant and Diffusion Profiles
Figure Complementary-error-function and Gaussian distribu-tions; the vertical axis is normalized to the peak con-centration Cs, while the horizon-tal axis is normal-ized to the char-acteristic length
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9. Diffused or Implanted IC Resistor (Fig 2.451)
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10. An IC Resistor with L = 8W (M&K)1
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11. Typical IC doping profile (M&K Fig. 2.441)
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12. Mobilities**
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13. IC Resistor Conductance
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14. An IC Resistor with Ns = 8, R = 8Rs (M&K)1
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15. The effect of lateral diffusion (M&K1)
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16. A serpentine pattern IC Resistor (M&K1)
R = NSRS NCRS
note: RC = 0.65RS
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17. References
1 and M&KDevice Electronics for Integrated Circuits, 2 ed., by Muller and Kamins, Wiley, New York, See Semiconductor Device Fundamentals, by Pierret, Addison-Wesley, 1996, for another treatment of the m model.
2Physics of Semiconductor Devices, by S. M. Sze, Wiley, New York, 1981.
3Semiconductor Physics & Devices, 2nd ed., by Neamen, Irwin, Chicago, 1997.
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