The bipolar devices considered include the p-n junction diode, the bipolar transistor, and thyristors. A description is provided of special microwave devices, giving attention to tunnel devices, IMPATT and related transit-time diodes, and transferred-electron devices. Photonic devices investigated include LED and semiconductor lasers, photodetectors, and solar cells.
Similar records in OSTI. GOV collections:. GOV Book: Physics of semiconductor devices 2nd edition. Title: Physics of semiconductor devices 2nd edition. Full Record Other Related Research. Abstract A resume is presented regarding the physics and properties of semiconductors, taking into account aspects of crystal structure, the energy bands, the carrier concentration at thermal equilibrium, carrier transport phenomena, basic equations for semiconductor device operation, and phonon spectra and optical, thermal, and high-field properties of semiconductors.
From Eq. Using Eq. Because the second term on the right-hand side of the Eq. From Fig. At K, all boron impurities are ionized. However, the mobilities and resistivities for these two samples are different.
Assuming complete ionization, the Fermi level measured from the intrinsic Fermi level is 0. Then from Eq. The value is comparable to the thermal velocity, the linear relationship between drift velocity and the electric field is not valid.
The intrinsic carriers density in Si at different temperatures can be obtained by using Fig. ND E 3. E 2. E Current Density 2. E 1. E 5. E 0. We can use following equations to determine the parameters of the diode. As the temperature increases, the total reverse current also increases. That is, the total electron current increases. The impact ionization takes place when the electron gains enough energy from the electrical field to create an electron- hole pair. When the temperature increases, total number of electron increases resulting in easy to lose their energy by collision with other electron before breaking the lattice bonds.
This need higher breakdown voltage. The obtained electrostatic potentials are 1. The depletion widths are 3. The total depletion width will be reduced when the heterojunction is forward-biased from the thermal equilibrium condition.
We can sketch p n x pn 0 curves by using a computer program: 1. By multiplying this 2 value by q and the cross-sectional area A, we can obtain the same expression as Q B. In Problem 3, 1. In Eq. W2 Therefore, the collector current is directly proportional to the minority carrier charge stored in the base.
And the collector current components are given by 1. The emitter efficiency can be obtained by I En IE I En The value is very close to unity. The mobility of an average impurity concentration of 6. Comparing the equations with Eq. Referring Eq. The neutral base width should be 0. The impurity concentration of the n1 region is cm For a reverse block voltage of V, we can choose a width such that punch-through occurs, i.
Co The bandgap in degenerately doped Si is around 1eV due to bandgap- narrowing effect. Pros: 1. Higher operation speed. High device density Cons: 1. More complicated fabrication flow. High manufacturing cost. Therefore, From Eq. The pinch-off voltage is qN D d12 1. By neglecting the second term in Eq. For same energy but a width of 8 meV, we use the same well thickness of 6. The resonant-tunneling current is related to the integrated flux of electrons whose energy is in the range where the transmission coefficient is large.
Take the solution which is the only practical one, i. The threshold current in Fig. The efficiencies are The segregation coefficient of boron in silicon is 0. It is smaller than unity, so the solubility of B in Si under solid phase is smaller than that of the melt. Therefore, the excess B atoms will be thrown-off into the melt, then the concentration of B in the melt will be increased.
The tail- end of the crystal is the last to solidify. Therefore, the concentration of B in the tail-end of grown crystal will be higher than that of seed-end. The reason is that the solubility in the melt is proportional to the temperature, and the temperature is higher in the center part than at the perimeter. Therefore, the solubility is higher in the center part, causing a higher impurity concentration there.
We have from Eq. The corresponding doping concentration varies from 2. From the Fig. Therefore, the As content will be lost when the temperature is increased. Thus the composition of liquid GaAs always becomes gallium rich.
We divide the wafer into four symmetrical parts for convenient dicing, and discard the perimeter parts of the wafer. Usually the quality of the perimeter parts is the worst due to the edge effects. For close-packing arrange, there are 3 pie shaped sections in the equilateral triangle. The molecular weight is The x value is about 0. The time required to grow 0. For the field oxide with an original thickness 0.
Another method is to use boron doped P-glass which will reflow at temperatures less than Moderately low temperatures are usually used for polysilicon deposition, and silane decomposition occurs at lower temperatures than that for chloride reactions.
In addition, silane is used for better coverage over amorphous materials such SiO 2. There are two reasons. One is to minimize the thermal budget of the wafer, reducing dopant diffusion and material degradation.
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