In this paper, the effects on insulated gate field-effect transistor device characteristics due to implantation of silicon into the gate insulator have been studied. Contrary to what one might have expected in an oxygen-deficient insulator, the primary defects generated, as detected by optically assisted injection of electrons into the gate insulators of damaged devices, are large quantities, as much as 1.3×1012 cm−2, of neutral electron traps (NET). Secondary types of defects found appear to be fixed negative charge, approximately 2.3×1011 cm−2 in the worse case, and a smaller amount of fixed positive charge (FPC), approximately 1.7×1011 cm−2 in the worse case. It was found that none of these defects could be removed by employing conventional postmetal annealing conditions in forming gas (10% H2, 90% N2) at 400 °C for up to 60 min. The defects created by ion implantation appear to be quite different from those created by x-ray or electron irradiation, where large quantities of FPC and NET are generated which can be annealed in a similar postmetal annealing cycles.

We have succeeded in developing encapsulated silicon-vacuum field-emission transistors by using integrated circuit technology. This success will accelerate the development of integrated circuit of silicon-vacuum field-emission devices. Preliminary electrical characteristics of these encapsulated silicon-vacuum field-emission transistors show very similar characteristics to the gated field-emitter diode. However, the turn-on voltage and the transconductance are lower compared to the open gated field emitters.

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Abstract— Cathodoluminescent flat‐panel displays can be made with field‐emitter arrays (FEAs). Using orientation‐dependent etching and a linear thermal‐oxidation process, uniform and reproducible FEAs which yield more than 10 μA per tip with less than 140‐Vdc extraction voltages have been fabricated. Modulation voltages are in the 40‐V region. These FEAs can be the basis for a simple and inexpensive cathodoluminescent flat‐panel display.

In the present paper, the residual electrical effects, before and after postmetal annealing, on insulated gate field‐effect transistor (IGFET) device characteristics due to implantation of oxygen at a dose of 1015 cm−2 into 36‐nm‐thick gate insulators following their growth have been studied. The primary defects detected via optically assisted injection of electrons into the gate insulators of the damaged IGFETs were neutral electron traps (NETs), present in concentrations as high as 1.4×1011 cm−2 . Secondary types of defects found appear to be fixed negative charge (FNC), approximately 0.7×1011 cm−2 in the worst case, and a smaller amount of fixed positive charge (FPC), less than 1010 cm−2 in the worst case. It is not surprising (unlike the case for silicon implantation under similar conditions) that a smaller number of defects is generated by oxygen implanted into gate insulators following its growth, since the device is subjected to a series of high‐temperature processing steps after the implantation. These high‐temperature processes appear to result in the redistribution and/or volatilization of most of the excess oxygen atoms; volatilization of silicon, on the other hand, is much less likely. Similar to what was observed with silicon‐implanted gate insulators, it was found that these defects could not be removed by employing conventional postmetal annealing (PMA) conditions in forming gas (10% H2 , 90% N2 ) at 400°C for 30 min. The defects created by ion implantation appear to be quite different from those created by x‐ray or electron irradiation, where large quantities of FPCs and NETs are generated, which can be annealed in PMA cycles. It is found that oxygen‐implanted gate insulators appear to be much more susceptible to x‐ray radiation than unimplanted devices. The residual defects in oxygen‐implanted devices, following x‐ray radiation and subsequent PMA annealing for up to 120 min, were found to be greater than that in unimplanted devices. The results with silicon ions earlier, and oxygen ions now, indicate that if the insulator is damaged by such species during processing, as might occur due to knock‐on from the gate electrode during source/drain formation, unannealable defects will form which would also tend to make the device structure more susceptible to radiation damage in a hostile environment, or to large hot electron drift, accompanying conventional use.