A rather large amount of shallow donors is created in p-type Czochralski silicon (Cz Si) wafers after a hydrogen plasma exposure at ∼270 °C (substrate temperature) and a subsequent annealing in the temperature range of 350-450 °C. This two-step process has been used for the fabrication p-n junction diodes at low temperatures. Current-voltage characteristics show that the breakdown voltages of these diodes are higher than 100 V. The diode leakage is found to be improved after slow ramp annealing at temperatures up to 250 °C. Deep level transient spectroscopy measurements reveal that the oxygen related thermal donor is not the dominant doping species as expected before.

Ballistic electron emission microscopy (BEEM) and deep level transient spectroscopy (DLTS) have been used to study the effects of substrate damage introduced by an ion-milling process in PtSi/n-Si Schottky contacts. Argon ions with well-defined energies of 300, 500, 700, 1000, 1500 eV were used to sputter n-type Si substrates in an ion beam sputtering system before metal deposition and silicide formation. Histograms of the PtSi/n-Si Schottky barrier height (SBH) measured by BEEM show that the mean SBH decreases with increasing ion energy, which can be explained as a result of donor-like defects that are introduced by the ion milling treatment. From DLTS measurements, we found direct evidence for the presence of such defects.

The recombination activity of oxygen precipitation related lattice defects in p- and n-type silicon is studied with photoluminescence (PL) and microwave absorption (MWA) techniques. A direct correlation is observed between the amount of precipitated oxygen and the extended defect density on one hand and the minority carrier lifetime and PL activity on the other hand. The PL analyses show as dominant features in the spectra the Dl and D2 lines. The relative amplitude of the D-lines in the different samples is investigated as a function of the oxygen content, defect density and excitation level. The results are correlated with those of complementary techniques and are interrelated on the basis of Shockley-Read-Hall (SRH) theory.

Results are reported of a Deep Level Transient Spectroscopy (DLTS) study of the conversion of the divacancy, with energy level at Ev+0.19eV, to a level at Ev+0.24eV after anneal at temperatures below its dissociation temperature (300°C). In literature both levels have been associated with the donor level of the divacancy.

Diodes processed on p-type Float Zone (FZ) and Czochralski (Cz) silicon wafers with boron concentration between 0.2 and 3E15 cm−3 are irradiated with 2 MeV electrons. Before and after anneal (200°C and 250°C) DLTS spectra are recorded to get a full electrical characterisation of the induced defects.

The observed conversion is proposed to be a gradual transformation of the divacancy to a divacancy-oxygen complex.

The results are presented of a fundamental study of electrically active damage introduced in silicon diodes by irradiation with the fission products resulting from the decay of a 252Cf source and with high energy protons. The influence of the oxygen content of the silicon substrate and the irradiation type on the damage formation is investigated using deep level transient spectroscopy. A radiation hardening effect by interstitial oxygen is observed. Bom types of irradiation create the same dominant defect levels but with different relative densities. The identification of the induced deep levels are confirmed by isochronal annealing results.

1007×100 μm2 n+− Si/p-Si1−x Gex diodes fabricated on conventional p-type Si substrates are irradiated at room temperature with 1-MeV electrons with fluences from 1.0×1014 to 1.0×1015 e/cm2 in a high voltage transmission electron microscope. The boron concentration and germanium fraction of the Si1−x Gex epitaxial layer used for the diodes in this study are 5×1017 cm−3 and x = 0.12, respectively. The degradation of diodes is investigated by means of current/voltage and capacitance/voltage measurements. The characteristics of the electrically active defects induced in the Si1−x Gex epitaxial layer by irradiation are also examined by using deep level transient spectroscopy and capacitance/temperature measurements. The degradation of the diode performance and the presence of deep levels are investigated as a function of electron fluence. In order to examine the recovery process, an isochronal thermal anneal is performed in the temperature range between 100 and 400°C.