SU997581A1 - Semiconductor device - Google Patents

Abstract

A SEMICONDUCTOR DEVICE based on a MIS structure containing a semiconductor, dielectric and metal layer, characterized in that, in order to influence the straightening coefficient and obtain a domed capacitance-voltage characteristic, the layers are made of a material that satisfies the following relations:, 3 , 2 f, iJ & 2 where the difference of the work function between the layers of the dielectric and the metal; LF2 is the difference of the work output between the dielectric and the semiconductor; L is the difference between the energies of the Ferm level and the bottom of the conduction band of the dielectric; g L is the difference between the energies of the Fer level (L m and the bottom of the conduction band of the semiconductor. CO x SP 00

Description

The invention relates to the field of semiconductor microelectronics and can be used in the case of a research institute for semiconductor devices based on MIS structures.

Known MJin-diode; consisting of a metal (M) layer, a dielectric layer (D, E of which a nonlinear semiconductor resistance layer is taken), and a semiconductor layer (P ;, the intermediate dielectric layer I1rath in such a diode is active, however, independent of the semiconductor role. Coefficient The type of diode is low because the interrelationship of the design parameters of the materials used, such as the work function L 1 J, is not taken into account:

The closest to the technical nature of the invention is a 2 semiconductor device based on a MIS structure containing layers of a semiconductor, a dielectric, and a metal. Ag., 0,. Is used as a dielectric layer in a semiconductor device.

However, such a device has an insufficient rectifier coefficient and,

; 4frame Parameters tl AI-AI „, a, -n Su;. Al-ZnO-p. „... i ,,

The aim of the invention is to increase the rectification rate and obtain dome-shaped volt-farad characteristics.

It is stated that in the proposed semiconductor device based on a MIS structure containing layers of a semiconducting dielectric and a metal, the layers are made of materials that satisfy the following relations: 3.2

1.7 fW2

where f is the difference between the work functions of the dielectric and metal layers; LF2 is the difference between the work functions of the dielectric and semiconductor layers;

level energy difference

a, Fermi and the bottom of the conduction band of the dielectric; level energy difference

 2 Fermi and bottom of the semiconductor conduction band. The invention is explained in the table and the drawing, where the table shows the energy parameters (& F, jF2, -L2-ZNuch-nennya contact potential difference, K - rectification factor) Si j y1-2n-Si, 16-6,136, 22-4.16 -6066 22-4,16-2,06

4% 0.2 j6.22-4, 326.22-4.28 1.94

2, 1.6 i; 6

and, 08c, 9 2 0; 3

2,420,68 1,3

057i, 56 .06

ii, 2o1, - 3.3

An external contact potential difference, which is distributed by contacting materials J to r-C, leads to the formation of spatial charge regions (PE), the curvature of the zones in the semiconductor and the dielectric. Since the resistivity of a dielectric is much greater than the resistivity of a metal and greater than the resistivity of a semiconductor, rf - /% 1, where O, is the charge of an electron) is concentrated on the dielectric,. Whereas the question is between the floor and a dielectric, the internal contact potential difference for electrons (as well as for holes) makes it possible to control when a voltage is applied to a conduction voltage and a valence and electric carriers that are involved in the current transfer and the formation of simple regions Charges

The operation of a semiconductor device based on a MIS structure (AI-ZnP-pSd) is based on the use of spatial charge regions. The presence of spatial charge regions (asymmetric in general) in the dielectric and semiconductor makes it possible to obtain unipolar conductivity and change the capacitance of the MIS structure not only in the depletion mode of the research institute of the semiconductor, but also in the enrichment mode. nnoy. In order for the interconnection of the contacting materials to be significant, it is necessary that the external contact potential differences are not as small as in the prototype (see the table Compliance with conditions that require dimensionless quantities in the mathematical record of the relationship between the parameters of the contacting materials that provide a positive effect the operation of the device requires the use of a ratio of values, for example, the table shows the values of this ratio. For an M-structure of M-Zn O-n Si, the external contact potential difference is large e, but the rectification coefficient is 10, since the tunneling mechanism of the current passage makes a large contribution. By comparing the values, the lower limit can be set. For the MIS structure A.1.1-ZnO-pSi 0.74 eV. The bending of the zones cannot be very large, since breakdown between the semiconductor and the dielectric is then possible. to be oce the bending of the zones H: N- (nQexp-cr / kT) 3 where Pd is the equilibrium carrier concentration in the bulk of the semiconductor; T - absolute temperature; K is the Boltzmann constant, Dl ZnO According to Yu-VSM 3, 4-i, b eV. Thus, the upper limit LF2, 2. However, the external contact potential difference is not sufficient to achieve the goal. Internal contact potential difference is sufficient. Since the drop probability is proportional to -V -, the internal contact potential should not be as large as in the prototype. The gablitz makes it possible to establish the limits of the possible variation of t,. The verification of the operation of the MIS-structure of Al-ZnO-pSi was carried out using the following parameters: thickness of zinc oxide film 560 A, thickness of p Si plate; - with p-10.0 ohm-cm 300 µm, diode area 2-1П cm. Volt-ampere characteristics were measured using standard equipment consisting of an AM1TSU120 h voltage source, BK7-3 / A4-M2 / voltage measuring instruments, M-95 current with an external P4 shunt, and a milliammeter. Voltage-capacitance characteristics were measured using an L2-7 bridge with an ITO-AO voltage source. Measurement was carried out before the procedure described in the instruction manual for the specified equipment. The measurement results are shown in the drawing, where in FIG. 1 shows the current-voltage characteristics: for p-type silicon, 1, and for p-type silicon, 2; on . 2 gives the capacitance-voltage characteristics: for silicon with n-type conductivity 3 and for silicon with p-type conductivity 4. Rectification coefficient. The shape of the capacitance-voltage characteristic differs from that known and has a dome-shaped shape, which creates additional possibilities for application in microelectronics. The use of the invention makes it possible to obtain semiconductor devices with a high rectifying coefficient and a dome-shaped voltage-capacitance characteristic.

Claims (4)

SEMICONDUCTOR DEVICE based on an MIS structure containing a layer of semiconductor, dielectric and metal, characterized in that, in order to increase the rectification coefficient and obtain a dome-shaped VLTF characteristic, the layers are made of material "satisfying the following ratios: 1.5 <<3, 2 1.7 4 Δ ₁ ! & _G <5-, 3, where 4f_, is the difference between the work functions between the layers of the dielectric and metal; 4 <t * 2 is the difference in the work function between the layers of the dielectric and the semiconductor; the energy difference between the Fermi level and the bottom of the conduction band of the dielectric; £ the difference in the energies of the Fer-G mi level and the bottom of the semiconductor conduction band. ABOUT