The recombination of chlorine atoms at surfaces

Chlorine atom recombination coefficient (γCl) measurements are reported for a variety of surfaces and at a range of surface temperatures. The surfaces include crystalline silicon, quartz, anodized aluminum, tungsten, stainless steel, polycrystalline silicon, and photoresist. Surface temperatures ranged from about −90 °C up to 85 °C. Measurements were made in a vacuum chamber with chlorine atoms and molecules effusing from an external discharge source as a molecular beam and impacting a selected surface. The incident and reflected beam compositions calculated using a modulated beam mass spectrometer were used to infer the recombination coefficient. At room temperature, the values of γCl ranged from below the detection sensitivity (about 0.01) for crystalline silicon to ∼0.85 for stainless steel. Other surfaces displayed intermediate values between these extremes. For example, γCl for polycrystalline silicon is about 0.2–0.3 at room temperature. All surfaces, except stainless steel, displayed increasing val...

[1]  M. Rossi,et al.  The heterogeneous interaction of Br(2P3/2) and Br(2P1/2) with surfaces of Teflon™ and polycrystalline nickel , 1995 .

[2]  Kazunori Tsujimoto,et al.  Low‐temperature reactive ion etching and microwave plasma etching of silicon , 1988 .

[3]  W. Rodebush,et al.  Atomic Chlorine and its Reaction with Hydrogen1 , 1933 .

[4]  Lewis,et al.  New mechanism for hydrogen desorption from covalent surfaces: The monohydride phase on Si(100). , 1989, Physical review letters.

[5]  G. D. Billing,et al.  Hydrogen and deuterium recombination rates on a copper surface , 1997 .

[6]  M. Rossi,et al.  Interaction of chlorine atom(2P3/2) and chlorine atom(2P1/2) with polycrystalline nickel surfaces , 1991 .

[7]  J. Gregus,et al.  Scaling of Si and GaAs trench etch rates with aspect ratio, feature width, and substrate temperature , 1995 .

[8]  V. M. Donnelly.  A simple optical emission method for measuring percent dissociations of feed gases in plasmas: Application to Cl2 in a high‐density helical resonator plasma , 1996 .

[9]  M. Vasile,et al.  Electron impact ionization cross sections of F2 and Cl2 , 1981 .

[10]  P. Nordine,et al.  Heterogeneous fluorine atom recombination/reaction on several materials of construction , 1976 .

[11]  C. Rettner.  Reaction of an H‐atom beam with Cl/Au(111): Dynamics of concurrent Eley–Rideal and Langmuir–Hinshelwood mechanisms , 1994 .

[12]  E. A. Ogryzlo.  HALOGEN ATOM REACTIONS: I. THE ELECTRICAL DISCHARGE AS A SOURCE OF HALOGEN ATOMS , 1961 .

[13]  J. Linnett,et al.  The kinetics of the recombination of oxygen atoms at a glass surface , 1956, Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences.

[14]  J. Linnett,et al.  The recombination of oxygen atoms at surfaces , 1958 .

[15]  Jane P. Chang,et al.  Kinetic study of low energy ion-enhanced polysilicon etching using Cl, Cl2, and Cl+ beam scattering , 1997 .

[16]  C. Rettner,et al.  Distinguishing the Direct and Indirect Products of a Gas-Surface Reaction , 1994, Science.

[17]  J. Amorim,et al.  On the use of actinometry to measure the dissociation in O2 DC glow discharges: determination of the wall recombination probability , 1995 .

[18]  J. Coburn,et al.  Molecular‐beam study of gas‐surface chemistry in the ion‐assisted etching of silicon with atomic and molecular hydrogen and chlorine , 1990 .

[19]  V. M. Donnelly.  Mass spectrometric measurements of neutral reactant and product densities during Si etching in a high‐density helical resonator Cl2 plasma , 1996 .

[20]  H. F. Winters,et al.  Etching reactions for silicon with F atoms: Product distributions and ion enhancement mechanisms , 1991 .

[21]  Wetzel,et al.  Absolute electron-impact-ionization cross-section measurements of the halogen atoms. , 1987, Physical review. A, General physics.

[22]  W. H. Weinberg,et al.  Hydrogen desorption from the monohydride phase on Si(100) , 1990 .

[23]  M. Lieberman,et al.  Role of etch products in polysilicon etching in a high-density chlorine discharge , 1996 .

[24]  H. P. Broida,et al.  Microwave Discharge Cavities Operating at 2450 MHz , 1964 .

[25]  C. Kolb,et al.  An ultrahigh vacuum compatible fluorine atom source for gas–surface reaction studies , 1986 .

[26]  Jane P. Chang,et al.  Kinetic study of low energy argon ion-enhanced plasma etching of polysilicon with atomic/molecular chlorine , 1997 .