This paper presents the first results of a photocapacitance investigation applied to the deep levels introduced by the 1.1 MeV proton bombardment into the Si PIN diodes. The ion density spectra asymptotic to the saturating value are measured at each wavelength using the forward injection in the dark in order to neutralize each deep level before photoexcitation. The present PHCAP method reveals the presence of proton-induced deep donors at 0.44 and 0.52 eV below the conduction band and a monotonic increase of the level density with increasing proton dosage. The Ec -0.79 eV deep level is detected even in virgin crystals, regardless of the proton irradiation. The PHCAP measurements after photoexcitation reveal the photoinduced emissions and capture characteristics of these deep levels and prove the photoinduced deionization of the ionized deep donors at 0.70-0.74 and 0.35-0.38 eV above the valence band. By varying the initially irradiating photon energy, the excitation PHCAP measurements also reveal the neutral state of the 0.38 eV + Ev ionized level to be 0.83 eV below the conduction band. From the PHCAP results on the emission and capture characteristics of the deep levels, it is shown that the amount of the Frank-Condon shifts (dFc) ofEc -0.44, 0.52, and 0.83 eV level are 0, 55, and 35 meV, respectively.

Intermittent injection of trisdimethylaminophosphorus (TDMAP) is applied for selective etching of the InP in ultrahigh vacuum by using molecular layer epitaxy equipment. The etching depth is controlled by the number of injection cycles of TDMAP in a self‐limiting fashion. The etch rate per injection cycle increases with the injection time of TDMAP and is saturated. The etch rate is well described by a Langmuir‐type equation. The etch rate is independent of the injection time at times longer than 0.3 s, and is also independent of the injection pressure of TDMAP. This is almost independent of the vacuum time. The activation energy for etching with TDMAP is determined to be 1.27 eV, which is half of that for the decomposition of phosphorus from InP substrate. Well‐controlled digital etching is realized at substrate temperatures as low as 350°C. © 1999 The Electrochemical Society. All rights reserved.

This paper reports the results of photocapacitance measurements applied to the metal‐ SiO2‐normalSi structure. Photocapacitance measurements under a constant capacitance condition determine the spatial distribution of deep levels existing at normalSi/SiO2 interface regions. The photocapacitance method revealed deep levels distributed in a spectral region of 0.4–1.05 eV optically, and an optical level located 1.05 eV below the conduction band in the n‐ normalSi/SiO2 interface region. With respect to p‐ normalSi/SiO2 , deep levels distributed at 0.4–0.85 eV and 0.85 eV, 1.05 eV levels above the valence band, were observed. Differences of interface level densities are shown as a function of Si conduction type and different preparations of oxide layers. Comparisons with the results of capacitance‐voltage measurements are also discussed. © 1999 The Electrochemical Society. All rights reserved.

No abstract