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US 5,256,579 AGranted
Tunable-frequency Gunn diodes fabrication with focused ion beams
AssigneeMassachusetts Institute of Technology
InventorsHenri Lezec, Khalid Ismail
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Abstract
The abstract isn’t available for this document.
Claims39
A method of making a planar Gunn diode capable of frequency-tunable and continuous-wave oscillations in the transit-time mode of operation, such method comprising the steps of:
- a. providing a semiconductor substrate terminate at a first location by a cathode electrode and terminated at a second location by an anode electrode;
- b. selecting, for the semiconductor substrate, a doping profile having a cross-sectional area which varies as a function of the distance from the first location;
- c. implanting in the semiconductor substrate ions of an impurity by using a focused ion beam, such that the cross-sectional area of the implantation varies along a path between the first location and the second location according to the selected doping profile;
- d. annealing the semiconductor for a suitable time and at a suitable temperature whereby at least some of the implanted ions are activated to become the charge carriers of the device.
1 more element
A method of making a planar Gunn diode capable of continuous wave oscillations in the transit-time mode of operation, such method comprising steps of:
- a. providing a semiconductor substrate terminated at a first location by a cathode electrode and terminated at a second location by an anode electrode;
- b. implanting in the semiconductor substrate ions of an impurity using an ion beam;
- and
- c. annealing the semiconductor for a suitable time and at a suitable temperature whereby at least some of the implanted ions are activated to form charge carriers in the device.
1 more element
A method of making a planar Gunn diode capable of continuous wave oscillations in the transit-time mode of operation, such method comprising steps of:
- a. providing a semiconductor substrate terminated at a first location by a cathode electrode and terminated at a second location by an anode electrode;
- b. implanting, using focused ion beam and a single implantation energy, ions of an impurity which ions have a low diffusion coefficient in the semiconductor substrate in the semiconductor substrate;
- c. annealing the semiconductor for a suitable time and at a suitable temperature whereby at least some of the implanted ions are activated to form charge carriers in the device;
- d. selecting for the semiconductor substrate, a doping profile having a doping concentration which varies as a function of the distance from the first location;
- and
- wherein the concentration of the implanted ions varies along a path between the first location and the second location according to the selecting doping profile.
3 more elements
A method of making a planar Gunn diode capable of continuous wave oscillations in the transit-time mode of operation, such method comprising the steps of:
- providing a semiconductor substrate terminated at a first location by a cathode electrode, terminated at a second location by an anode electrode and having a surface extending from the cathode to the anode;
- implanting in the semiconductor substrate ions of an impurity using an ion beam;
- annealing the semiconductor substrate for a suitable time and at a suitable temperature whereby at least some of the implanted ions are activated to form charge carriers in the device, wherein the charge carriers have a concentration which increases form the surface of the semiconductor material to a peak depth and which decreases from the peak depth.
A method of making a planar Gunn diode capable of continuous wave oscillations in the transit-time mode of operation, such method comprising steps of:
- a. providing a semiconductor substrate terminated at a first location by a cathode electrode and terminated at a second location by an anode electrode;
- b. implanting, using a focused ion beam and a single implantation energy, in the semiconductor substrate ions of an impurity which ions have a low diffusion coefficient in the semiconductor substrate;
- and
- c. annealing the semiconductor for a suitable time and at a suitable temperature whereby at least some of the implanted ions are activated to form charge carriers in the device.
1 more element
A method of making a planar Gunn diode capable of continuous wave oscillations in the transit-time mode of operation, such method comprising the steps of:
- providing a semiconductor substrate terminated at a first location by a cathode electrode, terminated at a second location by an anode electrode and having a surface extending from the cathode to the anode;
- implanting in the semiconductor substrate ions of an impurity using a focused ion beam;
- annealing the semiconductor substrate for a suitable time and at a suitable temperature whereby at least some of the implanted ions are activated to form charge carriers in the device, wherein the charge carriers have a concentration which increases from the surface of the semiconductor material to a peak depth and which decreases from the peak depth;
- selecting for the semiconductor substrate, a doping profile having a doping concentration which varies as a function of the distance from the first location;
- and
- wherein the concentration of the implanted ions varies along a path between the first location and the second location according to the selecting doping profile.
3 more elements
A method of making a planar Gunn diode capable of frequency-tunable and continuous-wave oscillations in the transit-time mode of operation, such method comprising the steps of:
- a. providing a semiconductor substrate terminated at a first location by a cathode electrode and terminated at a second location by an anode electrode;
- b. selecting, for the semiconductor substrate, a doping profile having a doping concentration which varies as a function of the distance from the first location;
- c. implanting in the semiconductor substrate ions of an impurity by using a focused ion beam, such that the concentration of the implanted ions varies along a path between the first location and the second location according to the selected doping profile;
- and
- d. annealing the semiconductor for a suitable time and at a suitable temperature whereby at least some of the implanted ions are activated to form the charge carriers of the device.
2 more elements
A method of making a planar Gunn diode capable of frequency-tunable and continuous-wave oscillations in the transit-time mode of operation, such method comprising the steps of:
- a. providing a semiconductor substrate terminated at a first location by a cathode electrode and terminated at a second location by an anode electrode;
- b. selecting, for the semiconductor substrate, a doping profile having a doping concentration which varies as a function of the distance from the first location;
- c. implanting in the semiconductor substrate ions of an impurity by using a focused ion beam, such that the concentration of the implanted ions varies along a path between the first location and the second location according to the selected doping profile;
- d. annealing the semiconductor for a suitable time and at a suitable temperature whereby at least some of the implanted ions are activated to form the charge carriers of the device;
- and
- e. patterning on the surface of the semiconductor intermediate the first and second locations at least one Schottky barrier gate.
3 more elements
A method of making a planar Gunn diode capable of frequency-tunable and continuous-wave oscillations in the transit-time mode of operation, such method comprising the steps of:
- a. providing a semiconductor substrate terminated at a first location by a cathode electrode and terminated at a second location by an anode electrode;
- b. selecting, for the semiconductor substrate, a doping profile having a cross-sectional area which varies as a function of the distance from the first location;
- c. implanting in the semiconductor substrate ions of an impurity by using a focused ion beam, such that the cross-sectional area of the implantation varies along a path between the first location and the second location according to the selected doping profile;
- d. annealing the semiconductor for a suitable time and at a suitable temperature whereby at least some of the implanted ions are activated to become the charge carriers of the device;
- and
- e. patterning on the surface of the semiconductor intermediate the first and second locations at least one Schottky barrier gate.
3 more elements
Dependencies are inferred from the claim text.