Thin oxides with in situ native oxide removal [n-MOSFETs]

1997 ◽  
Vol 18 (9) ◽  
pp. 417-419 ◽  
Author(s):  
A. Chin ◽  
W.J. Chen ◽  
T. Chang ◽  
R.H. Kao ◽  
B.C. Lin ◽  
...  
Keyword(s):  
Native Oxide ◽  
Oxide Removal

Polysilicon Emitter Transistors Manufactured using a Novel Limited Reaction Processing System

1989 ◽  
Vol 146 ◽  
Author(s):  
Fred Ruddell ◽  
Colin Parkes ◽  
B Mervyn Armstrong ◽  
Harold S Gamble
Keyword(s):  
Thermal Processing ◽  
Rapid Thermal Processing ◽  
Processing System ◽  
Bipolar Transistors ◽  
Native Oxide ◽  
Plasma Oxidation ◽  
Oxide Removal ◽  
Polysilicon Emitter ◽  
Reaction Processing

ABSTRACTThis paper describes a LPCVD reactor which was developed for multiple sequential in-situ processing. The system is capable of rapid thermal processing in the presence of plasma stimulation and has been used for native oxide removal, plasma oxidation and silicon deposition. Polysilicon layers produced by the system are incorporated into N-P-N polysilicon emitter bipolar transistors. These devices fabricated using a sequential in-situ plasma clean-polysilicon deposition schedule exhibited uniform gains limited to that of long single crystal emitters. Devices with either plasma grown or native oxide layers below the polysilicon exhibited much higher gains. The suitability of the system for sequential and limited reaction processing has been established.

Thermally Driven In-Situ Removal of Native Oxide Using Anhydrous Hydrogen Fluoride

1993 ◽  
Vol 318 ◽  
Author(s):  
Pushkar P. Apte ◽  
Heungsoo Park ◽  
Krishna C. Saraswat ◽  
C. R. Helms
Keyword(s):  
Hydrogen Fluoride ◽  
Native Oxide ◽  
Epitaxial Silicon ◽  
Crystal Silicon ◽  
Silicon Deposition ◽  
Native Oxides ◽  
Anhydrous Hydrogen Fluoride ◽  
Thermally Driven ◽  
Oxide Removal

ABSTRACTIn-situ native-oxide removal is critical for epitaxial single-crystal silicon deposition, for polysilicon emitters and contacts and for ultrathin gate dielectric films in integrated circuit (IC) fabrication. We have developed an in-situ, thermally-driven, anhydrous hydrogen fluoride (AHF)-based native-oxide removal technique in which the wafer is treated by AHF at low temperatures (300-400°C) and a short (10 sec) 950°C ‘spike’ in AHF-H2 immediately prior to Si deposition. This process removes native oxides formed by standard wet cleans such as HC1:H202 and NH4OH:H202, as well as native oxides formed by the clean-room ambient. Further, the technique is an effective pre-clean for both polysilicon and epitaxial silicon deposition. This flexibility, combined with other salient features such as simplicity and a low thermal budget, make the process eminently suited for IC fabrication.

Microanalysis of Tungsten Silicide/Polysilicon Interface: Effectiveness of in Situ Rie Clean on Removal of Native Oxide

1990 ◽  
Vol 182 ◽  
Author(s):  
Ronald S. Nowicki ◽  
Patrice Geraghty ◽  
David W. Harris ◽  
Gayle Lux
Keyword(s):  
Oxide Layer ◽  
Silicon Surface ◽  
Secondary Ion Mass Spectrometry ◽  
Film Deposition ◽  
Native Oxide ◽  
Native Oxide Layer ◽  
Tungsten Silicide ◽  
High Temperature Heat Treatment ◽  
Oxide Removal

AbstractThe presence of a thin (10-30Å) oxide (“native oxide”) layer on a silicon surface prior to the deposition of another film on that surface can contribute todifficulties with subsequent device processing steps, e.g. contact metallization and hightemperature annealing or oxidation. Thus, the in situ process capability of “native oxide” removal affords an advantage over the conventional method of aqueous hydrofluoric acid cleaning prior to a film deposition step. This study describes such a technique, in which an in situ pre-deposition clean with C2F6 gas, using reactive ion etching (RIE) prior to tungsten silicide deposition, is employed. This technique allows post-silicide deposition high-temperature heat treatment and wet oxidation without loss of film adhesion or other obvious degradative effects. We also report the useof Secondary Ion Mass Spectrometry (SIMS) to show that this procedure has een effective in the removal of the oxide layer prior to silicide deposition. This study includes definition of the RIE etch parameters which provide acceptable etch selectivity of the oxideto silicon, and avoidance of excessive fluoropolymer formation on the silicon surface.

In Situ Wafer Cleaning Prior to Selective HemiSpherical Grain (HSG) Poly-Silicon Deposition Using RT-CVD

1998 ◽  
Vol 525 ◽  
Author(s):  
B. J. Brosilow ◽  
S. Levy ◽  
Y. E. Gilboa
Keyword(s):  
Silicon Surfaces ◽  
Ex Situ ◽  
Native Oxide ◽  
Poly Silicon ◽  
Wafer Cleaning ◽  
Cleaning Procedures ◽  
Temperature Window ◽  
Oxide Removal ◽  
Cell Capacitance

ABSTRACTHemispherical grained (HSG) polycrystalline-silicon surfaces are used in DRAM manufacturing to enhance cell capacitance by increasing the surface area of the capacitor electrodes. We study the formation of HSG poly-silicon in a Rapid Thermal CVD (RT-CVD) cluster tool with in-situ native oxide removal. Compared to conventional ex-situ wet cleaning procedures, use of the in-situ native oxide removal both decreases the process temperature at which HSG formation occurs and increases the width of the temperature window within which desirable HSG layers are formed.

Processing of InP and GaAs Surfaces by Hydrogen and Oxygen Plasmas: In Situ Real Time Ellipsometric Monitoring

1996 ◽  
Vol 448 ◽  
Author(s):  
M. Losurdo ◽  
P. Capezzuto ◽  
G. Bruno
Keyword(s):  
Real Time ◽  
Uv Light ◽  
Native Oxide ◽  
Kinetics Of Oxidation ◽  
Hydrogen Plasmas ◽  
Defect Passivation ◽  
Hydrogen Exposure ◽  
Oxide Removal ◽  
Kinetics Of

AbstractRemote radiofrequency H2 and O2 plasma processing of InP and GaAs surfaces was investigated by in situ real time spectroscopic ellipsometry. Hydrogen plasmas were used for the native oxide removal and the defect passivation of III-V surfaces. The effect of hydrogen exposure time and of crystallographic orientation (GaAs (100), (110), (111)) on the chemistry and kinetics of oxygen removal and of phosphorus/arsenic depletion was investigated. Oxygen plasma anodization was used to grow oxide films on GaAs (100), (110) and (111) substrates. The effect of bias voltage and UV-light irradiation on the chemistry and kinetics of oxidation process and on the oxide properties was studied. The composition and morphology of the InP and GaAs surfaces resulting from these plasma treatments was described.

In Situ Diagnostics of Vuv Laser Cvd of Semiconductor Interfaces by Ftir Spectroscopy and Spectroscopic Ellipsometry

1995 ◽  
Vol 397 ◽  
Author(s):  
M. Barth ◽  
J. Knobloch ◽  
P. Hess
Keyword(s):  
Film Thickness ◽  
Bulk Material ◽  
Substrate Surface ◽  
Cluster Formation ◽  
Interface Layer ◽  
Native Oxide ◽  
Initial Growth ◽  
Difference Spectra ◽  
Si Substrates

ABSTRACTThe growth of high quality amorphous hydrogenated semiconductor films was explored with different in situ spectroscopic methods. Nucleation of ArF laser-induced CVD of a-Ge:H on different substrates was investigated by real time ellipsometry, whereas the F2 laser (157nm) deposition of a-Si:H was monitored by FTIR transmission spectroscopy. The ellipsometric studies reveal a significant influence of the substrate surface on the nucleation stage, which in fact determines the electronic and mechanical properties of the bulk material. Coalescence of initial clusters occurs at a thickness of 16 Å for atomically smooth hydrogen-terminated c-Si substrates, whereas on native oxide covered c-Si substrates the bulk volume void fractions are not reached until 35 Å film thickness. For the first time we present a series of IR transmission spectra with monolayer resolution of the initial growth of a-Si:H. Hereby the film thickness was measured simultaneously using a quartz crystal microbalance with corresponding sensitivity. The results give evidence for cluster formation with a coalescence radius of about 20 Å. Difference spectra calculated for layers at different depths with definite thickness reveal that the hydrogen-rich interface layer stays at the substrate surface and does not move with the surface of the growing film. The decrease of the Urbach energy switching from native oxide to H-terminated substrates suggests a strong influence of the interface morphology on the bulk material quality.

In situ removal of a native oxide layer from an amorphous silicon surface with a UV laser for subsequent layer growth

CrystEngComm ◽  
2018 ◽  
Vol 20 (44) ◽  
pp. 7170-7177 ◽  
Author(s):  
Christian Ehlers ◽  
Stefan Kayser ◽  
David Uebel ◽  
Roman Bansen ◽  
Toni Markurt ◽  
...  
Keyword(s):  
Laser Pulse ◽  
Amorphous Silicon ◽  
Oxide Layer ◽  
Silicon Surface ◽  
Layer Growth ◽  
Native Oxide ◽  
Native Oxide Layer ◽  
Uv Laser ◽  
Subsequent Layer

An in situ method for selectively heating a substrate by a laser pulse was modelled and investigated experimentally.

In-Situ UHV TEM Investigations of the Initial Stages of Cu(001) Oxidation

1997 ◽  
Vol 3 (S2) ◽  
pp. 583-584
Author(s):  
J. C. Yang ◽  
M. Yeadon ◽  
B. Kolasa ◽  
J. M. Gibson
Keyword(s):  
High Vacuum ◽  
Copper Film ◽  
Ultra High Vacuum ◽  
Native Oxide ◽  
In Situ Tem ◽  
Face Centered Cubic ◽  
Free Standing ◽  
Transmission Electron ◽  
Face Centered

We studied the beginning oxidation stage of a model metal system by in-situ transmission electron microscopy (TEM) in order to gain insights into the initial kinetics of oxidation. In-situ TEM experiments can distinguish between nucleation and growth since individual oxide islands are imaged. We chose to investigate Cu, since it is a simple face-centered cubic metal. Also, Cu is a highly promising metal interconnect material because of its low resistivity and good electromigration properties as compared to Al.Single crystal -1000Å 99.999% purity copper films were grown on irradiated NaCl in an UHV e-beam evaporator system. The free-standing copper film was placed on a specially designed holder, which permits resistive heating of the sample. The microscope used for this experiment is a modified ultra-high vacuum, with base pressure of 10−9 torr, JEOL200CX, operated at l00kV. To remove the native oxide formed during exposure in air, the Cu film was annealed at ∼350°C

Sign in / Sign up

Export Citation Format

Share Document