摘要:

Deep proton-isolated (GaAl)As/GaAs lasers have been fabricated in structures where the active layer was 40 μm from the surface. Proton-isolation masks have been made enabling high proton energies, up to 2.5 MeV, to be used. By chemically delineating the proton-bombarded regions studies have been made of proton penetration in (GaAl) As/GaAs laser structures. This work was extended to include a study of proton penetration in other III-V compound semiconductors and results show that the energy-range data for GaAs, InP and GaSb is very similar. The characteristics of deep proton-isolated (GaAl) As/GaAs lasers have been investigated and results are given which show that improvements to the external quantum efficiency, peak power operation and reliability can be realised by using this technique of laser fabrication.

DOI:10.1049/ij-ssed.1979.0001

出版商:IEE    

年代:1979

数据来源: IET

摘要:

A method for determining the surface-state charge densityQssof metal-thin tunnel oxide-silicon (m.i.s.) structures is presented, using the 3-terminal m.i.s. thyristor (m.i.s.t.) devices. Values of interface state charges are obtained fromI/Vcharacteristics of the device. Measurements were carried out and it was found that aQss= 1.6 × 10−7Ccm−2, equivalent to an electronic charge of 1012cm−2, is of the right order for thin oxides grown at low temperatures of 800°C, and is in agreement with other published results.

DOI:10.1049/ij-ssed.1979.0002

出版商:IEE    

年代:1979

数据来源: IET

摘要:

In the first part of this paper the effects of introducing specific interface trap configurations into the ideal m.o.s. system are considered while maintaining the condition for equilibrium. The theory is then used to fit an experimental curve and it is found that only three rectangular distributions placed appropriately in the energy gap are sufficient to give close agreement. In the second part the capacitance/voltage relationships are considered of an m.o.s. system biased with a linear voltage ramp of such rate as to generate the quasiequilibrium curve for part of the voltage range, and a nonequilibrium portion for the remainder. A theory is developed for the transition point and the subsequent nonequilibrium behaviour, based on the assumption that interface traps that interact only with the conduction band are the dominating influence. Experimental data are presented which provides reasonable agreement with the theory.

DOI:10.1049/ij-ssed.1979.0003

出版商:IEE    

年代:1979

数据来源: IET

摘要:

The discharge behaviour of m.n.o.s. structures with no applied voltage is investigated at temperatures from −155° C to 120° C for times from 10 to 104s. The decay rate is practically independent of the temperature up to 80° C but increases significantly at 120° C. The discharge curves are explained by direct tunnelling from traps, combined with the thermal excitation of these traps. The time dependence of the charge centroid is ascribed to a redistribution of the stored charge in the nitride. A correlation between the decay rate increase after write-erase cycling with the increased nitride conductivity is found.

DOI:10.1049/ij-ssed.1979.0004

出版商:IEE    

年代:1979

数据来源: IET

摘要:

The possibility of making a shift register using an array ofp+-i-n+diodes has been examined by investigating the transfer action of the on state of negative resistance characteristics between closely spacedp+-i-n+diodes. A gold-doped Si substrate is used to fabricate thep+-i-n+structure. The possibility of the transfer of the on state has been examined. The main requirements for transferring are as follows: (a) The array of diodes must be located within about 500 µm in lateral length, (b) The operation time of the transfer action must be within about 10µs. To clarify the transfer mechanism, experiments concerning the effect of carrier diffusion, Joule heat and recombination radiation due to on state current from one diode to the adjacent diode have been carried out. From the experimental results, it has been found that the transfer mechanism is dominated by carrier diffusion from the filamentary current path of one diode to the next.

DOI:10.1049/ij-ssed.1979.0005

出版商:IEE    

年代:1979

数据来源: IET

摘要:

The scanning electron microscope (s.e.m.) is widely used for the topographical examination and X-ray elemental analysis of integrated circuits, and is increasingly being used in electrical contrast modes. The voltage-contrast (v.c.) mode is particularly important because of the small dimensions of the devices found in current l.s.i. circuits which preclude the use of mechanical probes, and because of the minimal circuit loading which the electron beam imposes in high-frequency applications. Voltage contrast can now give a fair degree of measurement accuracy both in the static and dynamic cases. The dynamic situations often require the use of stroboscopic and sampling techniques, where the primary electron beam is chopped at a frequency locked to that of the signal being examined.

DOI:10.1049/ij-ssed.1979.0008

出版商:IEE    

年代:1979

数据来源: IET