World Abstracts on Microelectronics and Reliability
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adaptive equalization can be achieved at the receiver by processing only the phase of the sampled signal. Additionally, experimental results are presented which demonstrate the superiority of this design over conventional coherent demodulators.
Static n-MOS RAM idles on trickle current. F. A. SCHERPENBERG. Electronics 129 (27 January 1981). On-chip circuits route battery power into the random-access memory's write-enable line; high-resistance loads limit current needs.
C-MOS a-d converter interfaces easily with many microprocessors. THOMASM. FREDERIKSEN.Electronics 150 (24 March 1981). With a span accommodation down to 180mV, this 8-bit unit can also replace a 12-bit analog-todigital device in some applications.
Stress-sensitive properties of silicon-gate MOS devices. HIROAKI MIKOSHIBA. Solid-St. Electron. 24, 221 (1981). Stress-sensitive properties were measured on both p- and nchannel silicongate MOS devices fabricated on (100) Si at room temperature. Stress-induced variations in drain currents for both enhancement- and depletion-mode MOS transistors with various channel-dopings were measured over a wide range of gate biases. In addition to piezoresistance effect, remarkable drain-current variations were observed at weak-inversion and explained theoretically in terms of changes in minority carrier densities due to energy band shifts by stresses. Elastoresistance shearconstants for polycrystalline-silicon gate layers were also obtained and compared with coefficients for source-drain diffused layers. Further, the elastoresistance of p-type polycrystalline-silicon films was investigated on dopingconcentration dependences. A theoretical model for polycrystalline-silicon elastoresistance was developed based on the barrier model for conductivity in polycrystallinesilicon. Results obtained from the model were compared with the experimental results and found to be in good agreement at higher doping-concentrations than trap density.
Silicon temperature sensors require little compensation. JOHN GOSCH. Electronics 3E (5 May 1981). Gold contacts on n crystal form sensor that's nearly linear over -50°-to + 150°C range; resistors can do compensation. Semiconductor device sensitive to magnetic field gradient. N. J. JANAV1CIENE, I. S. LEVITAS,J. K. POZELA and K. K. STALIORAITIS.Solid-St. Electron. 24, 407 (1981). In the paper theoretical and experimental analysis of the performance of a device sensitive to the gradient of magnetic induction is presented. The device employs magnetogradient effect and consists of a semiconducting resistor fabricated from germanium and has sensitivity of the order of 5 mV mm Gs- 1. 3-d MOS FETs shrink static RAM cells and analog circuit blocks. JOHN G. POSA. Electronics 39 (5 May 1981). Single device well merges two or more transistors; a differential pair fits in one well, a memory cell in two.
CAD station aims at VLSI design. MARTIN MARSHALL. Electronics 171 (7 April 1981). Intended for a designer working on a silicon subdivision, dual-8086 unit lowers perstation cost of CAD efforts.
Functional and in-circuit testing team up to tackle VLSI in the 'g0s. PETER HANSEN. Electronics 189 (21 April 1981). The combination of techniques speeds checkout and fault isolation on high-density boards while cutting software development effort.
Multifunction chip plays many parts in analog design. DAVID L. GILLOOLYand PAUL HENNEUSE.Electronics 121 (7 April 1981). Containing TTL-gated transconductance amplifiers, a buffer, and a comparator, the device cuts the components count of data-conversion and control systems.
7. SEMICONDUCTOR INTEGRATED CIRCUITS, DEVICES AND MATERIALS A model for the breakdown characteristics of p-channel MOS transistor protection devices. H. MAES, P. SIX and W. SANSEN. Solid-St. Electron. 24, 523 (1981). Gate controlled diodes, MOS transistors with grounded gate, source and substrate and gate controlled pnn+ structures are compared when used as a protective input device on p-channel MOS integrated circuits. For this purpose two pulse techniques are developed which allow an accurate determination of the dynamic resistance by minimizing the walk-out of the breakdown voltage during the measurement. While the breakdown voltage does not differ much for the different types of devices, the dynamic resistance however is found to be considerably lower for the MOS transistor than for both other devices. For these low values the series resistance of the drain and source diffusion is shown to constitute already an important contribution. The lower dynamic resistance of MOST's can be ascribed to parasitic bipolar transistor operation during breakdown. The identification of this mechanism leads to a simple model for the MOS transistor in breakdown which has been experimentally verified and confirmed. Guidelines for the definition of the source diffusion for an optimal protective functioning can be obtained from this model. Mobility of majority carriers in doped noncompensated silicon. T. I, TosIc, D. A. TJAPKINand M. M. JEV~C. Solid-St. Electron. 24, 577 (1981). A unique theoretical model of mobility calculation of majority carriers in n-type doped noncompensated silicon at T = 300 K is given. Starting with the Fermi statistics and spherical but non-parabolic
equienergetic surfaces, a procedure to calculate mobility is proposed which allows to take complex dependence between the density of states and energy in heavily doped semiconductors under consideration. The following types of scattering are observed; scattering by ionized impurities, acoustic-mode scattering and intervalley scattering. Besides, electron-electron scattering influence is also taken under consideration. Based on the suggested model the calculation of mobility in a phosphorus doped silicon in the impurity concentration range from 1015 to 102°cm-3, and the comparison with the experiment were done.
Electron light scattering from doped silicon. I. P. IPATOVA, A. V. SUBASHIEVand V. A. VOITENKO.Solid-St. Commun. 37, 893 (1981). The light scattering from homogeneous intervalley fluctuations of free carriers density in n-Si is calculated for any degree of the electron gas degeneration. Effects of the external stress on the scattering spectrum are considered. Results allow to explain the basic qualitative results of the experiment [7]. Interface edge effect and its contribution to the frequency dispersion of metal-oxide-semiconductor admittance. Y. C. SUN and C. T. SAH. Solid-St. Electron. 24, 569 (1981). Room temperature frequency dispersion of the admittance of Metal-Oxide-Semiconductor (MOS) capacitors made on non-degenerate n-type silicon substrate with (111) surface orientation was studied. A simplified lumped equivalent circuit model which takes into account the interface edge effect, i.e. carrier generation-recombination-trapping via