EP0504603B1 - Dispositif semiconducteur émetteur d'électrons - Google Patents

Dispositif semiconducteur émetteur d'électrons Download PDF

Info

Publication number
EP0504603B1
EP0504603B1 EP92102746A EP92102746A EP0504603B1 EP 0504603 B1 EP0504603 B1 EP 0504603B1 EP 92102746 A EP92102746 A EP 92102746A EP 92102746 A EP92102746 A EP 92102746A EP 0504603 B1 EP0504603 B1 EP 0504603B1
Authority
EP
European Patent Office
Prior art keywords
type semiconductor
semiconductor region
electron emission
region
high density
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP92102746A
Other languages
German (de)
English (en)
Other versions
EP0504603A1 (fr
Inventor
Nobuo C/O Canon Kabushiki Kaisha Watanabe
Norio C/O Canon Kabushiki Kaisha Kaneko
Masahiko C/O Canon Kabushiki Kaisha Okunuki
Takeo C/O Canon Kabushiki Kaisha Tsukamoto
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Canon Inc
Original Assignee
Canon Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from JP4557991A external-priority patent/JP3135070B2/ja
Priority claimed from JP5559791A external-priority patent/JP3137267B2/ja
Priority claimed from JP23445791A external-priority patent/JPH0574331A/ja
Priority claimed from JP23445691A external-priority patent/JPH0574330A/ja
Application filed by Canon Inc filed Critical Canon Inc
Publication of EP0504603A1 publication Critical patent/EP0504603A1/fr
Application granted granted Critical
Publication of EP0504603B1 publication Critical patent/EP0504603B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01JELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J1/00Details of electrodes, of magnetic control means, of screens, or of the mounting or spacing thereof, common to two or more basic types of discharge tubes or lamps
    • H01J1/02Main electrodes
    • H01J1/30Cold cathodes, e.g. field-emissive cathode
    • H01J1/308Semiconductor cathodes, e.g. cathodes with PN junction layers

Definitions

  • the present invention relates to a semiconductor electron emission device having an electron emission portion comprised of a Schottky barrier junction between a metal material or metallic compound material and a semiconductor for emitting electrons from a solid surface thereof.
  • Such a semiconductor electron emission device is one in which an electron emission portion is fabricated by forming a p-type semiconductor layer and an n-type semiconductor layer on a semiconductor substrate, and depositing cesium on the surface of the n-type semiconductor layer to have a decreased work function of the surface. And a reverse bias voltage is applied across a pn junction formed of the p-type semiconductor layer and the n-type semiconductor layer to cause the avalanche breakdown to make hot electrons, and emit the electrons from the electron emission portion in a direction perpendicular to the surface of the semiconductor substrate.
  • a semiconductor electron emission device in which a Schottky barrier junction is formed of the p-type semiconductor and a metal material, or the p-type semiconductor and a metallic compound, and a reverse bias voltage is applied across the Schottky barrier junction to cause the avalanche breakdown to make hot electrons and emit the electrons from the electron emission portion in a direction perpendicular to the surface of the semiconductor substrate, as described in Japanese Laid-Open Patent Application No. 1-220328.
  • the avalanche breakdown is caused in the high density p-type semiconductor region where the depletion layer width is formed thinnest, so that electrons having high energy produced therein are emitted from a solid surface to the outside.
  • the shape of the depletion layer around the pn junction or Schottky barrier junction has a radius of curvature determined by a carrier density of semiconductor and an applied voltage, and the electric field is more concentrated on the depletion layer than in other regions. Accordingly, the breakdown or leakage of the current around the depletion layer may occur at a lower applied voltage than the avalanche breakdown occurs in the high density p-type semiconductor region so that the device characteristics may be deteriorated.
  • the electron emission device having the pn junction or Schottky barrier junction, it is possible to increase the radius of curvature around the depletion layer with a decreased carrier density of the p-type semiconductor around the high density p-type semiconductor region where the avalanche breakdown occurs, thereby preventing the breakdown at the lower voltage, but the electrical resistance between an electrode for supplying carriers and the high density p-type semiconductor region where the avalanche breakdown occurs may increase, causing the operating voltage of device to rise, and a problem with the deterioration of device may occur due to the Joule heating.
  • a guard ring structure of high density n-type semiconductor was formed, concentrically with the high density p-type semiconductor region, within the p-type semiconductor region.
  • the depletion layer was formed continuously from the high density p-type semiconductor region outward to the p-type semiconductor region and the high density n-type semiconductor layer so as to have a large radius of curvature in the most outside region, thereby preventing the breakdown or the leakage of current around the depletion layer.
  • a manufacturing process such as the ion injection or the thermal diffusion for forming the ring-like n-type semiconductor region (guard ring structure) at a high density, or a process for forming the ohmic junction electrode to apply the voltage to the guard ring of the high density n-type semiconductor is necessary, in which there is a problem that the manufacturing process is complex.
  • the conventional semiconductor electron emission device it is required to supply electrons sufficiently to the high density p-type semiconductor region defining the avalanche amplification, when emitting electrons produced by the avalanche amplification mechanism.
  • the high density p-type semiconductor region is surrounded by the p-type semiconductor region having a high resistivity, and thus spaced away from the semiconductor or metallic electrode having a low resistivity for supplying electrons.
  • the current is concentrated in the high density p-type semiconductor region and the neighborhood thereof, so that the Joule heat is generated in the region having a high resistance, and it was difficult to prevent the breakage or deterioration of device due to the temperature elevation, or the fluctuation in the emission amount of electrons.
  • EP-A-0 331 373 discloses a semiconductor electron emission device having an electron emission portion comprised of a Schottky barrier junction between a metal material or a metallic compound material and a semiconductor for emitting electrons from a solid surface thereof, and implicitly a semiconductor electron emission device having an electron emission portion comprised of a pn-junction.
  • the shape of the depletion area around the electron emission area depends strongly from the carrier density, and the electric field is more concentrated on the depletion layer than in other regions. Accordingly, the breakdown or leakage of the current around the depletion layer may occur at a lower applied voltage than if the avalanche breakdown occurs in the high density p-type semiconductor region intrinsically required. Thus, the device characteristics are deteriorated.
  • the present invention was achieved in the light of the problems associated with the conventional arts as above described, and aimed to provide a smaller semiconductor electron emission device in which the device structure and the manufacturing process can be simplified, and a higher speed of device in the operation can be attained, while resolving the above-mentioned conventional problems.
  • Fig. 1 is a cross-sectional view showing a first example of a semiconductor electron emission device according to the present invention.
  • Fig. 2 is a view showing one example of an energy band for the semiconductor electron emission device of Schottky barrier junction.
  • Fig. 3 is a diagram showing one example of the current-voltage characteristics for the semiconductor electron emission device according to the present invention.
  • Fig. 4 is a diagram showing another example of the current-voltage characteristics for the semiconductor electron emission device according to the present invention.
  • Fig. 5 is a cross-sectional view showing a second example of a semiconductor electron emission device according to the present invention.
  • Figs. 6A and 6B are cross-sectional views showing a third example of a semiconductor electron emission device according to the present invention.
  • Fig. 7 is a cross-sectional view showing a fourth example of a semiconductor electron emission device according to the present invention.
  • Fig. 8 is a cross-sectional view showing a fifth example of a semiconductor electron emission device according to the present invention.
  • Figs. 9A and 9B are cross-sectional views showing a sixth example of a semiconductor electron emission deivce according to the present invention.
  • a second p-type semiconductor region having a lower carrier density and a third p-type semiconductor region having a further lower carrier density are formed around a first p-type semiconductor region of high density bringing about the avalanche breakdown.
  • a depletion layer the shape of which is thinnest in the first p-type semiconductor region so that the electric field is likely to be concentrated thereon. Accordingly, it is possible to bring about the avalanche breakdown efficiently only in the first p-type semiconductor region.
  • the series resistance value of semiconductor electron emission devices can be decreased by using the fourth p-type semiconductor region having a higher carrier density than the second p-type semiconductor region as the passage for the supply of carriers to the first p-type semiconductor region.
  • Fig. 1 is a cross-sectional view showing a semiconductor electron emission device of Schottky barrier junction type in the first example of the present invention.
  • the semiconductor electron emission device in this example is a Schottky barrier junction device in which a cylindrical high density p-type semiconductor region 105 which is a first p-type semiconductor region and a p-type semiconductor region 104, which is a fourth p-type semiconductor region, for supplying carriers to the high density p-type semiconductor region 105 are disposed in contact with each other on a substantial central portion of a high density p-type semiconductor substrate 101, a p-type semiconductor region 103 which is a second p-type semiconductor region and a low density p-type semiconductor region 102 which is a third p-type semiconductor region are disposed concentrically outwardly around the high density p-type semiconductor region 105 and the p-type semiconductor region 104, and a Schottky electrode 108 which is a metallic film for forming the Schottky barrier junction with the high density p-type semiconductor region 105 is disposed on the surface of the device.
  • the semiconductor electron emission device in this example is provided with an ohmic junction electrode 106 to the high density p-type semiconductor substrate 101 and an electrode wiring 109 to the Schottky electrode 108 for applying a reverse voltage to the Schottky barrier junction, the reverse voltage being applied from a power source 110.
  • the electrode wiring 109 is in contact with the Schottky electrode 108 on an insulating film 107 formed on the low density p-type semiconductor region 102 in order to prevent the short circuit with each p-type semiconductor region as previously described.
  • 111 shows the shape of a depletion layer end in a state where the reverse voltage is applied
  • 112 shows a region where the avalanche breakdown occurs with the application of the reverse voltage.
  • the bottom Ec of a conduction band for the p-type semiconductor is at a higher energy level than the vacuum level E VAC for the metal electrode forming the Schottky barrier, so that the avalanche breakdown is brought about.
  • An electron produced by the avalanche breakdown obtains a higher energy than the lattice temperature with the electric field within a depletion layer produced at an interface between semiconductor and metal electrode, and injected from the p-type semiconductor into the metal electrode forming the Schottky barrier junction.
  • the electron having a greater energy than the work function on the surface of metal electrode forming the Schottky barrier junction is discharged into the vacuum. Accordingly, the treatment for the surface of metal electrode to have a lower work function leads to an increase in the emission amount of electrons, as previously described.
  • FIG. 1 A manufacturing process of the semiconductor electron emission device as shown in Fig. 1 will be described specifically by way of an example.
  • the semiconductor electron emission device thus fabricated was installed within a vacuum chamber within which the degree of vacuum was retained at about 1x10 -7 Torr, and a voltage of 7V was applied between the ohmic junction electrode 106 and the electrode wiring 109 from a power source 110, so that the electron emisson of about 15pA was observed from the surface of the Schottky electrode 108 above the high density p-type semiconductor region 105. If the applied voltage (device voltage) was sequentially increased up to 10V, the electron emission amount (emission current) was sequentially increased up to about 100pA, as shown in Fig. 3.
  • a depletion layer 111 spreads about 0.04 ⁇ m beyond a Schottky barrier interface with the Schottky electrode 108 in the high density p-type semiconductor region 105, when this device voltage is applied.
  • the electric field is most concentrated on an avalanche region 112 of the high density p-type semiconductor region 105, in which region the avalanche breakdown occurs most efficiently.
  • a semiconductor electron emission device which was fabricated by changing only the Be density of the p-type semiconductor region 104 which is a fourth p-type semiconductor region for supplying carriers to the high density p-type semiconductor region 105 which is a first p-type semiconductor region to 3x10 18 cm -3 in the fabrication conditions as above described, was installed within the same vacuum chamber. If a device voltage of 5V was applied to the semiconductor electron emission device from the power source 110, the electron emission (emission current) of about 20pA was observed from the surface of the Schottky electrode 108 above the high density p-type semiconductor region 105. If the device voltage was sequentially increased up to 7V, the emission current was also sequentially increased up to about 100pA.
  • GaAs was used as the semiconductor, but other semiconductor materials such as Si, Ge, GaP, AlAs, GaAsP, AlGaAs, SiC, BP, AlN, or diamond are applicable in principle, and particularly, the material of indirect transition type and having a wide band gap is preferable.
  • the semi-insulating region can be fabricated by the use of various endogenic defects or residual impurities within the crystal, and purposely added compensating impurities. When this semi-insulating region is formed, undoped crystal not containing the dopant is also applicable because of its semi-insulating property.
  • the material for the ohmic junction electrode 106 requires to form the Schottky junction with the p-type semiconductor, and may be, for example, Al, Au or LaB 6 , in addition to tungsten (w), as commonly well known.
  • the electron emission efficiency increases with smaller work function of the electrode surface, as previously described, the electron emission efficiency can be increased by coating a material of low work function such as Cs on the surface, when the work function of the material is large.
  • Fig. 5 is a cross-sectional view showing a semiconductor electron emission device of pn junction type in the second example of the present invention.
  • the semiconductor electron emission device in this example is a pn junction device having an electron emission portion in which a cylindrical high density p-type semiconductor region 505 which is a first p-type semiconductor region and a p-type semiconductor region 504, which is a fourth p-type semiconductor region, for supplying carriers to the high density p-type semiconductor region 505 are disposed in contact with each other on a substantial central portion of a high density p-type semiconductor substrate 501, and a p-type semiconductor conductor region 503 which is a second p-type region and a low density p-type semiconductor region 502 which is a third p-type semiconductor region are disposed concentrically outwardly around the high density p-type semiconductor region 505 and the p-type semiconductor region 504, and a high density n-type semiconductor region 506 which is an n-type semiconductor region for forming the pn junction with the high density p-type semiconductor region 505 is disposed thereon.
  • the semiconductor electron emission device in this example is provided with an ohmic junction electrode 507 to the high density p-type semiconductor substrate 501, an ohmic junction electrode 509 to the high density n-type semiconductor region 506, and a low work function coating 510 formed on the high density n-type semiconductor region 506, for applying a reverse voltage to the pn junction, the reverse voltage being applied from a power source 511.
  • the ohmic junction electrode 509 is in contact with the high density n-type semiconductor region 506 via an insulating film 508 formed along an edge portion of the surface on the low density p-type semiconductor region 502 in order to prevent the short circuit with the low density p-type semiconductor region 502.
  • 512 shows the shape of a depletion layer end in a state where the reverse voltage is applied
  • 513 shows a region where the avalanche breakdown occurs with the application of the reverse voltage.
  • a manufacturing process of the semiconductor electron emission device of pn junction type will be described specifically by way of an example.
  • the semiconductor electron emission device thus fabricated was installed within a vacuum chamber which was retained at about 1x10 -11 Torr or less, and a device voltage of 6V was applied between the ohmic junction electrodes 507 and 509 from the power source 511, so that the electron emission of about 0.1 ⁇ A was observed from the surface of the low work function coating 510 (Cs) above the high density p-type semiconductor region 505.
  • a device voltage of 6V was applied between the ohmic junction electrodes 507 and 509 from the power source 511, so that the electron emission of about 0.1 ⁇ A was observed from the surface of the low work function coating 510 (Cs) above the high density p-type semiconductor region 505.
  • Fig. 6 is a view showing a multi semiconductor electron emission device of Schottky barrier type provided with a plurality of electron emission portions, in a third example of the present invention, in which Fig. 6A is a plan view thereof, and Fig. 6B is a cross-sectional view taken along the line A-A' of Fig. 6A.
  • the multi semiconductor electron emission device of this example is provided with four electron emission portions 600A, 600B, 600C and 600D, like a matrix, on a high density p-type semiconductor region 602 formed on a semiconductor substrate 601.
  • the electron emission portion 600A Since the electron emission portions 600A, 600B, 600C and 600D all have the same constitution, the electron emission portion 600A will be exemplified.
  • the electron emission portion 600A has the same constitution as in the previous first example, comprising a high density p-type semiconductor region 606A which is a first p-type semiconductor region, a p-type semiconductor region semiconductor 605A which is a fourth p-type region disposed in contact with the high density p-type semiconductor region 606A for supplying carriers to the high density p-type semiconductor region 606A, a p-type semiconductor region 604A which is a second p-type semiconductor region located around the high density p-type semiconductor region 606A and the p-type semiconductor region 605A, a low density p-type semiconductor region 603 which is a third p-type semiconductor region located around the p-type semiconductor region 604A, and a Schottky electrode 611A for forming the Schottky barrier junction with the high density p-type semiconductor region 606A.
  • the electrode wiring 610A is in contact with the Schottky electrode 611A on an insulating film 608 formed on the low density p-type semiconductor region 603 in order to prevent the short circuit with each p-type semiconductor region as previously described.
  • the ohmic junction electrode 609 is connected via the high density p-type semiconductor region 607 to the high density p-type semiconductor region 602, and in this example, provided at two positions as shown in Fig. 6A.
  • This ohmic junction electrode 609 is a common electrode to the four electron emission portions 600A, 600B, 600C and 600D.
  • the Schottky electrode 611A may be connected in common with Schottky electrodes 611B, 611C and 611D (611C, 611D are not shown) of other electron emission portions 600B, 600C and 600D, in which case as the ohmic junction electrode 609 is commonly used, the four electron emission portions 600A, 600B, 600C and 600D are controlled simultaneously for the electron emission operation.
  • the Schottky electrodes 611A, 611B, 611C and 611D of the electron emission portions 600A, 600B, 600C and 600D are independent of each other, the control for each electron emission portion 600A, 600B, 600C and 600D is allowed.
  • the portion except for the ohmic junction electrode 609 is covered via a supporting member 612 made of insulating material with a gate 613 composed of metallic film provided on the insulating layer 608.
  • This gate 613 is formed with opening portions 614A, 614B, 614C and 614D at positions corresponding to and upward of the electron emission portions 600A, 600B, 600C and 600D, respectively, whereby electrons emitted from each electron emission portion 600A, 600B, 600C and 600D are passed through the opening portions 614A, 614B, 614C and 614D outward.
  • a manufacturing process of the multi semiconductor electron emission device will be described specifically by way of an example.
  • the multi semiconductor electron emission device having the four electron emission portions 600A, 600B, 600C, 600D was completed.
  • a multi semiconductor electron emission device having the electron emission portions arranged like a matrix, 20 in the X direction, and 10 in the Y direction, was fabricated, and installed within a vacuum chamber within which the degree of vacuum was at about 1x10 -7 Torr. If a reverse voltage of 7V was applied to the entire area of the electron emission portions, the electron emission of about 20nA in total was observed. Also, by applying a reverse voltage only between arbitrary ohmic junction electrode 609 and arbitrary electrode wiring 610, it was observed that only device located at its intersection emitted electrons. In this way, with this example, it is possible to form an electron emission device having the same electron emission characteristics as a conventional multi semiconductor electron emission device and simply fabricated.
  • the n-type semiconductor region having a low carrier density is formed around a first p-type semiconductor region having a high density bringing about the avalanche breakdown.
  • the second p-type semiconductor region as the passage of supplying carriers to the first p-type semiconductor region, it is possible to make the series resistance of device an appropriate value. Accordingly, the operating speed can be increased.
  • Fig. 7 is a cross-sectional view showing a semiconductor electron emission device of Schottky barrier junction type in the fourth example of the present invention.
  • the semiconductor electron emission device in this example is a Schottky barrier junction device in which a cylindrical high density p-type semiconductor region 703 which is a first p-type semiconductor region and a p-type semiconductor region 704, which is a second p-type semiconductor region, for supplying carriers to the high density p-type semiconductor region 703 are disposed in contact with each other on a substantial central portion of a high density p-type semiconductor substrate 701, a low density n-type semiconductor region 702 which is an n-type semiconductor region is disposed concentrically outwardly around the high density p-type semiconductor region 703 and the p-type semiconductor region 704, and a Schottky electrode 708 which is a metallic film for forming the Schottky barrier junction with the high density p-type semiconductor region 703 is disposed on the surface of the device.
  • the semiconductor electron emission device in this example is provided with an ohmic junction electrode 706 to the high density p-type semiconductor substrate 701 and an electrode wiring 707 to the Schottky electrode 708 for applying a reverse voltage to the Schottky barrier junction, the reverse voltage being applied from a power source 709.
  • the electrode wiring 707 is in contact with the Schottky electrode 708 on an insulating film 705 formed on the low density n-type semiconductor region 702 in order to prevent the short circuit with each p-type semiconductor region as previously described.
  • 710 shows the shape of a depletion layer end in a state where the reverse voltage is applied.
  • the electron emission process in the semiconductor electron emission device using the Schottky barrier junction of the present invention is the same as described in Fig. 2.
  • a manufacturing process of the semiconductor electron emission device as shown in Fig. 7 will be described specifically by way of an example.
  • the semiconductor electron emission device thus fabricated was installed within a vacuum chamber within which the degree of vacuum was retained at about 1x10 -7 Torr, and a voltage of 7V was applied between the ohmic junction electrode 706 and the electrode wiring 709 from a power source 709, so that the electron emission of about 15pA was observed from the surface of the Schottky electrode 708 above the high density p-type semiconductor region 703. If the applied voltage (device voltage) was sequentially increased up to 10V, the electron emission amount (emission current) was also sequentially increased up to about 100pA, as shown in Fig. 3.
  • a depletion layer 710 spreads about 0.04 ⁇ m beyond a Schottky barrier interface with the Schottky electrode 708 in the high density p-type semiconductor region 703, when this device voltage is applied.
  • the electric field is most concentrated on a portion of the high density p-type semiconductor region 703, in which region the avalanche breakdown occurs efficiently.
  • a semiconductor electron emission device fabricated by changing only the Be density of the p-type semiconductor region 704 which is a second p-type semiconductor region for supplying carriers to the high density p-type semiconductor region 703 which is a first p-type semiconductor region to 3x10 18 cm -3 in the fabrication conditions as above described, was installed within the same vacuum chamber. If a device voltage of 5V was applied to the semiconductor electron emission device from the power source 709, the electron emission (emission current) of about 20pA was observed from the surface of the Schottky electrode 708 above the high density p-type semiconductor region 703. If the device voltage was sequentially increased up to 7V, the emission current was also sequentially increased up to about 100pA.
  • GaAs was used as the semiconductor, but other semiconductor materials such as Si, Cc, GaP, AlAs, GaAsP, AlGaAs, SiC, BP, AlN, or diamond are applicable in principle, and particularly, the material of indirect transition type and having a wide band gap is preferable.
  • the material for the ohmic junction electrode 706 requires to form the Schottky barrier junction with the p-type semiconductor, and may be, for example, Al, Au or LaB 6 , in addition to tungsten (W), as commonly well known.
  • W tungsten
  • the electron emission efficiency increases with smaller work function of the electrode surface, as previously described, the electron emission efficiency can be increased by coating a material of low work function such as Cs on the surface, when the work function of the material is large.
  • Fig. 8 is a cross-sectional view showing a semiconductor electron emission device of pn junction type in the fifth example of the present invention.
  • the semiconductor electron emission device in this example is a pn junction device having an electron emission portion in which a cylindrical high density p-type semiconductor region 803 which is a first p-type semiconductor region and a p-type semiconductor conductor region 804, which is a second p-type region, for supplying carriers to the high density p-type semiconductor region 803 are disposed in contact with each other on a substantial central portion of a high density p-type semiconductor substrate 801, a low density n-type semiconductor region 802 which is a second n-type semiconductor region is disposed concentrically outwardly around the high density p-type semiconductor region 803 and the p-type semiconductor region 004, and a high density n-type semiconductor region 805 which is a first n-type semiconductor region for forming the pn junction with the high density p-type semiconductor region 803 is disposed thereon.
  • the semiconductor electron emission device in this example is provided with an ohmic junction electrode 807 to the high density p-type semiconductor substrate 801, an ohmic junction electrode 808 to the high density n-type semiconductor region 805, and a low work function coating 809 formed on the high density n-type semiconductor region 805, for applying a reverse voltage to the pn junction, the reverse voltage being applied from a power source 810.
  • the ohmic junction electrode 808 is in contact with the high density n-type semiconductor region 805 via an insulating film 806 formed along an edge portion of the surface on the low density p-type semiconductor region 802 in order to prevent the short circuit with the low density n-type semiconductor region 802.
  • 811 shows the shape of a depletion layer end in a state where the reverse voltage is applied.
  • a manufacturing process of the semiconductor electron emission device of pn junction type will be described specifically by way of an example.
  • the semiconductor electron emission device thus fabricated was installed within a vacuum chamber which was retained at about 1x10 -11 Torr or less, and a device voltage of 6V was applied between the ohmic junction electrodes 807 and 808 from the power source 810, so that the electron emission of about 0.1 ⁇ A was observed from the surface of the low work function coating 809 (Cs) above the high density n-type semiconductor region 805.
  • a device voltage of 6V was applied between the ohmic junction electrodes 807 and 808 from the power source 810, so that the electron emission of about 0.1 ⁇ A was observed from the surface of the low work function coating 809 (Cs) above the high density n-type semiconductor region 805.
  • Fig. 9 is a view showing a multi semiconductor electron emission device of Schottky barrier type provided with a plurality of electron emission portions, in a sixth example of the present invention, in which (a) is a plan view thereof, and (b) is a cross-sectional view taken along the line A-A' of (a).
  • the multi semiconductor electron emission device of this example is provided with four electron emission portions 900A, 900B, 900C and 900D, like a matrix, on a high density p-type semiconductor region 902 formed on a semiconductor substrate 901.
  • the electron emission portion 900A Since the electron emission portions 900A, 900B, 900C and 900D all have the same constitution, the electron emission portion 900A will be exemplified.
  • the electron emission portion 900A has the same constitution as in the previous fourth example, comprising a high density p-type semiconductor region 904A which is a first p-type semiconductor region, a p-type semiconductor region 905A which is a second p-type semiconductor region disposed in contact with the high density p-type semiconductor region 904A for supplying carriers to the high density p-type semiconductor conductor region 904A, a low density n-type semiconductor region 903 which is a n-type semiconductor region located around the high density p-type semiconductor region 904A and the p-type semiconductor region 905A, and a Schottky electrode 910A for forming the Schottky barrier junction with the high density p-type semiconductor region 904A.
  • the electrode wiring 909A is in contact with the Schottky electrode 910A on an insulating film 907 formed on the low density n-type semiconductor region 903 in order to prevent the short circuit with each p-type semiconductor region as previously described.
  • the ohmic junction electrode 908 is connected via the high density p-type semiconductor region 906 to the high density p-type semiconductor region 902, and in this example, provided at two positions as shown in Fig. 9A.
  • This ohmic junction electrode 908 is a common electrode to the four electron emission portions 900A, 900B, 900C and 900D.
  • the Schottky electrode 910A may be connected in common with Schottky electrodes 910B, 910C and 910D (910C, 910D are not shown) of other electron emission portions 900B, 900C and 900D, in which case as the ohmic junction electrode 908 is commonly used, the four electron emission portions 900A, 900B, 900C and 900D are controlled simultaneously for the electron emission operation.
  • the Schottky electrodes 910A, 910B, 910C and 910D of the electron emission portions 900A, 900B, 900C and 900D are independent of each other, the control for each electron emission portion 900A, 900B, 900C and 900D is allowed.
  • the portion except for the ohmic junction electrode 908 is covered via a supporting member 911 made of insulating material with a gate 912 composed of metallic film provided on the insulating layer 907.
  • This gate 912 is formed with opening portions 913A, 913B, 913C and 913D at positions corresponding to and upward of the electron emission portions 900A, 900B, 900C and 900D, respectively, whereby electrons emitted from each electron emission portion 900A, 900B, 900C and 900D are passed through the opening portions 913A, 913B, 913C and 913D outward.
  • a manufacturing process of the multi semiconductor electron emission device will be described specifically by way of an example.
  • the multi semiconductor electron emission device having the four electron emission portions 900A, 900B, 900C, 900D were completed.
  • a multi semiconductor electron emission device having the electron emission portions arranged like a matrix, 20 in the X direction, and 10 in the Y direction, was fabricated, and installed within a vacuum chamber within which the degree of vacuum was at about 1x10 -7 Torr. If a reverse voltage of 7V was applied to the entire area of the electron emission portions, the electron emission of about 20nA in total was observed. Also, by applying a reverse voltage only between arbitrary ohmic junction electrode 908 and arbitrary electrode wiring 909, it was observed that only device located at its intersection emitted electrons. In this way, with this example, it is possible to form an electron emission device having the same electron emission characteristics as a conventional multi semiconductor electron emission device and simply fabricated.
  • the present invention it is possible to make faster the operating speed of the device by providing the region of small resistivity in the vicinity of the high density p-type semiconductor region bringing about the avalanche breakdown. Further, it is possible to avoid the breakage or deterioration of the device due to the Joule heating in the vicinity of the high density p-type semiconductor region bringing about the avalanche breakdown, and reduce the fluctuation in the electron emission amount.
  • the present invention can exhibit the following effects owing to the constitution as above described.

Landscapes

  • Cold Cathode And The Manufacture (AREA)
  • Electrodes Of Semiconductors (AREA)

Claims (21)

  1. Dispositif semiconducteur d'émission d'électrons ayant une partie d'émission d'électrons constituée d'une jonction à barrière de Schottky entre une matière du type métal ou une matière du type composé métallique (108) et un semiconducteur pour émettre des électrons (e-) à partir d'une surface pleine de cette matière,
       caractérisé en ce que
    ladite partie d'émission d'électrons comporte :
    une première région (105) en semiconducteur de type p provoquant le claquage par avalanche en formant ladite jonction à barrière de Schottky ;
    une deuxième région (103) de semiconducteurs de type p située autour de ladite première région (105) à semiconducteur de type p ;
    une troisième région (102) de semiconducteur de type p située autour de ladite deuxième (103) de semiconducteur de type p ; et
    une quatrième région (104) de semiconducteur de type p destinée à fournir des porteurs à ladite première région (105) de semiconducteur de type p.
  2. Dispositif selon la revendication 1,
       caractérisé en ce que
       la relation de densité entre des densités de porteurs desdites première à quatrième régions (102 à 105) de semiconducteur de type p est telle que (première région 105 de semiconducteur de type p) > (quatrième région 104 de semiconducteur de type p) > (deuxième région 103 de semiconducteur de type p) > (troisième région 102 de semi-conducteur de type p).
  3. Dispositif selon la revendication 1,
       caractérisé en ce que
       la relation de densité entre des densités de porteurs desdites première à quatrième régions de semi-conducteur de type p est telle que (quatrième région de semiconducteur de type p) >/= (première région de semi-conducteur du type p) > (deuxième région de semiconducteur de type p) > (troisième région de semiconducteur de type p).
  4. Dispositif semiconducteur d'émission d'électrons ayant une partie d'émission d'électrons constituée d'une jonction pn entre un semiconducteur de type n et un semiconducteur du type p pour émettre des électrons à partir d'une surface pleine de cette partie,
       caractérisé en ce que
    ladite partie d'émission d'électrons comporte :
    une région (506) de semiconducteur de type n située sur ladite surface pleine pour former ladite jonction pn ;
    une première région (505) de semiconducteur du type p provoquant le claquage par avalanche en formant ladite jonction pn avec ladite région (506) de semiconducteur du type n ;
    une deuxième région (503) de semiconducteur de type p située autour de ladite première région (505) de semiconducteur de type p ;
    une troisième région (502) de semiconducteur de type p située autour de ladite deuxième région (503) de semiconducteur de type p ; et
    une quatrième région (504) de semiconducteur de type p pour fournir des porteurs à ladite première région de semiconducteurs de type p.
  5. Dispositif selon la revendication 4,
       caractérisé en ce que
       la relation de densité entre les densités de porteurs desdites première à quatrième régions (502 à 505) de semiconducteur de type p et ladite région (506) de semiconducteur de type n est telle que (région 506 de semiconducteur de type n) > (première région 505 de semiconducteur de type p) > (quatrième région 504 de semiconducteur de type p) > (deuxième région 503 de semiconducteur du type p) > (troisième région 502 de semiconducteur de type p).
  6. Dispositif selon la revendication 4,
       caractérisé en ce que
       la relation de densité entre des densités de porteurs desdites première et quatrième régions de semi-conducteur de type p de ladite région de semiconducteur de type n telle que, (région 506 de semiconducteur de type n) > (quatrième région 504 de semiconducteur de type p) >/= (première région 506 de semiconducteur de type p) > (deuxième région 503 de semiconducteur de type p) > (troisième région 502 de semiconducteur du type p).
  7. Dispositif semiconducteur d'émission d'électrons ayant une partie d'émission d'électrons constituée d'une jonction à barrière de Schottky ayant une matière du type métal ou une matière du type composé métallique et un semiconducteur pour émettre des électrons à partir d'une surface pleine de cette partie,
       caractérisé en ce que
    ladite partie d'émission d'électrons comporte :
    une première région (703) de semiconducteur du type p provoquant le claquage par avalanche en formant ladite jonction à barrière de Schottky ;
    une deuxième région (704) de semiconducteur de type p, située en contact avec ladite première région (703) de semiconducteur du type p, pour fournir des porteurs à ladite première région (703) de semiconducteur de type p ; et
    une région (702) de semiconducteur du type n située autour de ladite première région (703) de semiconducteur de type p, pour former une jonction pn avec ladite première région (703) de semiconducteur de type p, ainsi que pour former ladite jonction à barrière de Schottky avec ladite matière du type métal ou ladite matière (708) du type composé métallique.
  8. Dispositif selon la revendication 7,
       caractérisé en ce que
       la relation de densité entre les densités de porteurs desdites première et deuxième régions (703, 704) de semiconducteur de type p et ladite région (702) de semiconducteur de type n est telle que (première région 703 de semiconducteur de type p) > (deuxième région 704 de semiconducteur de type p) > (région 702 de semiconducteur de type n).
  9. Dispositif selon la revendication 7,
       caractérisé en ce que
       la relation de densité entre les densités de porteurs desdites première et deuxième régions (703, 704) de semiconducteur de type p et de ladite région (702) de semiconducteur de type n est telle que (deuxième région 704 de semiconducteur de type p) >/= (première région 703 de semiconducteur de type p) > (région 702 de semiconducteur de type n).
  10. Dispositif semiconducteur d'émission d'électrons ayant une partie d'émission d'électrons constituée d'une jonction pn entre un semiconducteur de type n et un semiconducteur de type p pour émettre des électrons à partir d'une surface pleine de cette partie,
       caractérisé en ce que
    ladite partie d'émission d'électrons comporte :
    une première région (805) de semiconducteur de type n située sur une surface pleine ;
    une première région (803) de semiconducteur de type p provoquant ledit claquage par avalanche en formant ladite jonction pn avec ladite première région (805) de semiconducteur de type n ;
    une deuxième région (804) de semiconducteur de type p située en contact avec ladite première région (803) de semiconducteur de type p pour fournir les porteurs à ladite première région (803) de semiconducteur de type p ; et
    une deuxième région (802) de semiconducteur du type n, située autour de ladite première région (803) de semiconducteur de type p, pour former la jonction pn avec ladite première région (803) de semiconducteur du type p.
  11. Dispositif selon la revendication 10,
       caractérisé en ce que
       la relation de densité entre les densités de porteurs desdites première et deuxième régions (803, 804) de semiconducteur de type p et desdites première et deuxième régions (802, 805) de semiconducteur de type n est telle que (première région 805 de semiconducteur de type n) > (première région 803 de semiconducteur de type p) > (deuxième région 804 de semiconducteur de type p) > (deuxième région 802 de semiconducteur du type n).
  12. Dispositif selon la revendication 10,
       caractérisé en ce que
       la relation de densité entre les densités de porteurs desdites première et deuxième régions (803, 804) de semiconducteur du type p et desdites première et deuxième régions (802, 805) de semiconducteur de type n est telle que (première région 805 de semiconducteur de type n) > (deuxième région 804 de semiconducteur de type p) >/= (première région 803 de semiconducteur du type p) > deuxième région (802) de semiconducteur de type n).
  13. Dispositif selon les revendications 1 à 6,
       caractérisé en ce que
       lesdites première régions (105, 505) de semiconducteur de type p et ladite quatrième région (104 ; 504) de semiconducteur de type p de ladite partie d'émission d'électrons sont en contact.
  14. Dispositif selon l'une quelconque des revendications précédentes 1 à 12,
       caractérisé en ce que une électrode pour définir la direction de projection d'électrons émis depuis ladite partie d'émission d'électrons est prévue au voisinage de ladite surface pleine.
  15. Dispositif selon l'une quelconque des revendications 1 à 12,
       caractérisé en ce que
       une électrode pour définir l'énergie cinétique d'électrons émis à partir de ladite partie d'émission d'électrons est prévue au voisinage de ladite surface pleine.
  16. Dispositif selon l'une quelconque des revendications précédentes 1 à 3 et 7 à 9,
       caractérisé en ce que
       une matière, ayant un travail d'extraction différent de celui de ladite matière du type métal ou de ladite matière du type composé métallique, est déposée sur la surface de ladite partie d'émission d'électrons formée d'une matière du type métal ou d'une matière du type composé métallique formant la barrière à jonction de Schottky.
  17. Dispositif selon l'une quelconque des revendications précédentes 1 à 12,
       caractérisé en ce que
       ladite partie d'émission d'électrons est formée sur un substrat semiconducteur.
  18. Dispositif selon l'une quelconque des revendications précédentes 1 à 12,
       caractérisé en ce que
       plusieurs parties d'émission d'électrons (600A à 600D) sont prévues sur le même substrat.
  19. Dispositif selon la revendication 18,
       caractérisé en ce que
       ledit même substrat est un substrat semiconducteur.
  20. Dispositif selon la revendication 18,
       caractérisé en ce que
       plusieurs parties d'émission d'électrons (600A à 600D) sont électriquement indépendantes pour émettre des électrons séparément.
    21. Dispositif selon l'une quelconque des revendications précédentes 1 à 12,
       caractérisé en ce que
       lesdites régions de semiconducteur de type p ou lesdites régions de semiconducteur de type n de la partie d'émission d'électrons sont formées par le procédé d'injection ionique.
EP92102746A 1991-02-20 1992-02-19 Dispositif semiconducteur émetteur d'électrons Expired - Lifetime EP0504603B1 (fr)

Applications Claiming Priority (8)

Application Number Priority Date Filing Date Title
JP45579/91 1991-02-20
JP4557991A JP3135070B2 (ja) 1991-02-20 1991-02-20 半導体電子放出素子
JP55597/91 1991-02-28
JP5559791A JP3137267B2 (ja) 1991-02-28 1991-02-28 半導体電子放出素子
JP23445791A JPH0574331A (ja) 1991-09-13 1991-09-13 半導体電子放出素子
JP234456/91 1991-09-13
JP234457/91 1991-09-13
JP23445691A JPH0574330A (ja) 1991-09-13 1991-09-13 半導体電子放出素子

Publications (2)

Publication Number Publication Date
EP0504603A1 EP0504603A1 (fr) 1992-09-23
EP0504603B1 true EP0504603B1 (fr) 1997-07-16

Family

ID=27461730

Family Applications (1)

Application Number Title Priority Date Filing Date
EP92102746A Expired - Lifetime EP0504603B1 (fr) 1991-02-20 1992-02-19 Dispositif semiconducteur émetteur d'électrons

Country Status (3)

Country Link
EP (1) EP0504603B1 (fr)
AT (1) ATE155610T1 (fr)
DE (1) DE69220823T2 (fr)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE69911012T2 (de) 1998-06-11 2004-06-17 Petr Viscor Flacher elektronenemitter

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL184589C (nl) * 1979-07-13 1989-09-01 Philips Nv Halfgeleiderinrichting voor het opwekken van een elektronenbundel en werkwijze voor het vervaardigen van een dergelijke halfgeleiderinrichting.
NL8600675A (nl) * 1986-03-17 1987-10-16 Philips Nv Halfgeleiderinrichting voor het opwekken van een elektronenstroom.
JP2788243B2 (ja) * 1988-02-27 1998-08-20 キヤノン株式会社 半導体電子放出素子及び半導体電子放出装置

Also Published As

Publication number Publication date
EP0504603A1 (fr) 1992-09-23
DE69220823D1 (de) 1997-08-21
ATE155610T1 (de) 1997-08-15
DE69220823T2 (de) 1998-01-22

Similar Documents

Publication Publication Date Title
KR100338140B1 (ko) 전계 방사형 전자원
EP0532019B1 (fr) Dispositif semi-conducteur émetteur d'électrons
US5138402A (en) Semiconductor electron emitting device
US7170223B2 (en) Emitter with dielectric layer having implanted conducting centers
US5414272A (en) Semiconductor electron emission element
US5107311A (en) Semiconductor light-emitting device
EP0504603B1 (fr) Dispositif semiconducteur émetteur d'électrons
US6577058B2 (en) Injection cold emitter with negative electron affinity based on wide-gap semiconductor structure with controlling base
JP2809078B2 (ja) 電界放出冷陰極およびその製造方法
EP0720779A1 (fr) Dispositif a effet de transfert d'electrons
JP2002359380A (ja) ターンオフ時間の短い光導電スイッチ
JP2586834B2 (ja) 単一電子素子とその製造方法
JPH0574328A (ja) 半導体電子放出素子
JPH0574331A (ja) 半導体電子放出素子
EP0630084B1 (fr) Laser à semi-conducteur
JPH06162918A (ja) 半導体電子放出素子並びにその製造方法
JPH0574329A (ja) 半導体電子放出素子
JP3403165B2 (ja) 電子放出素子の製造方法
JP3260502B2 (ja) 電子放出素子
JP3135070B2 (ja) 半導体電子放出素子
JPH0574330A (ja) 半導体電子放出素子
JP3137267B2 (ja) 半導体電子放出素子
JPH0574332A (ja) 半導体電子放出素子
JPH0794103A (ja) 金属−絶縁体−金属型電子放出素子およびそれを用いた電子線放出装置等の応用機器の駆動方法
JPH0778553A (ja) 微小電界放出陰極装置およびその製造方法

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FR GB GR IT LI LU NL PT SE

17P Request for examination filed

Effective date: 19930209

17Q First examination report despatched

Effective date: 19931227

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AT BE CH DE DK ES FR GB GR IT LI LU NL PT SE

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LI

Effective date: 19970716

Ref country code: GR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 19970716

Ref country code: ES

Free format text: THE PATENT HAS BEEN ANNULLED BY A DECISION OF A NATIONAL AUTHORITY

Effective date: 19970716

Ref country code: DK

Effective date: 19970716

Ref country code: CH

Effective date: 19970716

Ref country code: BE

Effective date: 19970716

Ref country code: AT

Effective date: 19970716

REF Corresponds to:

Ref document number: 155610

Country of ref document: AT

Date of ref document: 19970815

Kind code of ref document: T

REG Reference to a national code

Ref country code: CH

Ref legal event code: EP

REF Corresponds to:

Ref document number: 69220823

Country of ref document: DE

Date of ref document: 19970821

ITF It: translation for a ep patent filed

Owner name: SOCIETA' ITALIANA BREVETTI S.P.A.

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Effective date: 19971016

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: PT

Effective date: 19971022

ET Fr: translation filed
REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LU

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 19980219

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: NL

Payment date: 20050203

Year of fee payment: 14

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20050208

Year of fee payment: 14

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20050216

Year of fee payment: 14

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20050217

Year of fee payment: 14

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20060219

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: IT

Payment date: 20060228

Year of fee payment: 15

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: NL

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20060901

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20060901

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20060219

NLV4 Nl: lapsed or anulled due to non-payment of the annual fee

Effective date: 20060901

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

Effective date: 20061031

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20060228

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20070219