philipp_1963#

H. R. Philipp and H. Ehrenreich, “Optical properties of semiconductors”, Phys. Rev. 129, 1550 (1963)

Source record · Catalogue · Review register

Source kind: measurement

Recorded technique: Near-normal-incidence reflectance of Si, Ge, GaP, GaAs, InAs and InSb, 1.5-25 eV, with a vacuum grating monochromator (Johnson’s design, off-axis pivot), a tungsten lamp or a capillary discharge lamp, sodium-salicylate-coated photomultipliers; etched samples, exposed to air for the minimum time needed for mounting, then to the monochromator’s ‘poor vacuum’. Below 1.5 eV the reflectance is extrapolated to values computed from dielectric-constant measurements. Kramers-Kronig analysis for eps_1, eps_2 and the energy-loss function -Im eps^-1 (p. 1551).

Materials in structured entries: None recorded.

Dataset quantities: None recorded.

Contents: 0 datasets; 0 formulas.

Curation notes#

Journal pages 1550-1560 = pdf pages 1-11. Identity checked against the first page. NOTHING IS TRANSCRIBED as a dataset: the optical data of silicon are in figures only, and the one table holds plasma energies, for which the vocabulary has no quantity.

WHAT THE PAPER HOLDS FOR SILICON (figures, not digitised): - Fig. 3 (pp. 1552-1553): reflectance R, eps_1, eps_2 and -Im eps^-1 of Si (with Ge, InAs, GaAs, GaP) against photon energy to 25 eV, from the Kramers-Kronig analysis. - Fig. 4 (p. 1556): experimental and theoretical eps_1 and eps_2 (the theory applies above about 12 eV, abstract); for Si the one adjustable parameter is the valence relaxation time, tau_v = 1.6e-16 s (caption). - Fig. 5 (p. 1557): n_eff against E; for silicon it ‘appears to saturate very nearly at a value of four electrons per atom as expected’, with a slight overshoot (p. 1557). - Fig. 6 (p. 1557): eps_0,eff against E; silicon’s ‘saturate[s] at a value corresponding to the independently measured low-frequency dielectric constant’ (p. 1557-1558), with no d-band contribution. - Fig. 7(b) (p. 1559): -Im eps^-1 of Si from the optical data and from characteristic energy-loss experiments (Dimigen, Z. Physik 165, 53 (1961)).

TABLE I (p. 1558; tbl_9092a0513e62, checked against its image), plasma energies in eV (no vocabulary quantity; notes only). Silicon: free-electron omega_Pv (four valence electrons per atom) 16.6; effective Omega_Pv 16.6; eps_1(omega) = 0 at 15.0; maximum of -Im eps^-1 from the optical data 16.4, and from electron energy loss 16.9 (footnote a, Dimigen). The same columns for Ge (15.5, 16.2, 13.8, 16.0, 16.4), GaP (16.6, 16.3, 13.3, 16.9), GaAs (15.5, 12.3, 9.7, 14.7) and InSb (12.7, 11.5, 10.9, 12.0, 13.0). Text: in Si the next filled band ‘lies about 80 eV below the valence bands’ (pp. 1553, 1557, citing Phillips and Kleinman); Si has no d band, so its effective and free-electron plasma frequencies coincide.

ACCURACY. ‘The samples are conceivably subject to atmospheric contamination and the data should be treated with some caution until further studies ... can be made on bulk surfaces prepared under conditions of ultrahigh vacuum’ (p. 1551); the sum-rule analysis ‘depends very sensitively on the absolute values of eps_2 and, hence, of the reflectance’ (p. 1558). No numerical uncertainty is stated. Temperature not stated (room temperature).

NUMERIC ROUTE. Palik’s handbook chapter on silicon (edwards_1985, Table XII) does NOT tabulate this paper’s values: its Philipp rows (5-20 eV, tag [26]) are from Philipp, J. Appl. Phys. 43, 2836 (1972) and a 1982 private communication, on chemically prepared surfaces; it cites this group’s work only as Philipp and Taft 1960 [25] and Philipp and Ehrenreich 1967 (Semiconductors and Semimetals, Vol. 2) [27]. So no tabulation of these 1963 curves is known here; they are not digitised (TC-699: edwards_1985’s [26] values are the printed numbers of Philipp’s later silicon data over the same range).

Recorded bibliographic identity status: VALIDATED_WITH_WARNINGS. This concerns identification of the source; it does not establish the scientific correctness of its contents.

Datasets#

No datasets are recorded.

Formulas#

No formulas are recorded.

Corrections#

No dataset errata are recorded in this source record.

Formula corrections, where recorded, appear with their formulas above. Curation notes may also discuss corrections or unresolved interpretation. Consult the review register for the checks and decisions.