EP0480689A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Ion implantation and surface processing method and apparatus
Assignee: Raytheon Co
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Filing: 1991-10-09
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Granted: —
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Expires: 2011-10-09
Abstract
Abstract A capacitor (58) is charged to a high potential or voltage from a power source (52). A plasma switch, (56) preferably a CROSSATRON modulator switch, is periodically closed and opened to discharge the capacitor (58) into an object (12) for implantation with ions from a plasma (19) in a plasma source ion implantation apparatus (10). The periodic discharge results in the application of high voltage negative pulses to the object (12), causing ions from the plasma (19) to be accelerated toward, and implanted into the object (12). A pulse transformer (92) is preferably provided between the plasma switch (56) and capacitor (58), and the object (12) to step up the voltage of the pulses and enable the plasma switch (56) to operate at lower voltage levels. The plasma switch (56) enables high duty factor and power operation, and may be combined with arc detection and suppression circuitry (64) to prevent arcing between the object (12) and plasma (19). A second power source (52), capacitor (58), and plasma switch (56) may be provided to apply positive pulses to the object (12) in alternation with the negative pulses to cause generation of the plasma, or to accelerate electrons into the object (12) for performing thermally assisted ion implantation, surface annealing, and the like.
Inventors
- 👤 Dan M. Goebel
- 👤 Jesse N. Matossian
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 03:06
CPC Classifications
H; H05; H05H; H05H1/00; H05H1/24; H01; H01J; H01J37/00; H01J37/32; H01J37/32431; H01J37/32697; C; C23; C23C; C23C14/00; C23C14/22; C23C14/48; H01J37/30; H01J37/317; H01J37/3171; H01J37/32009; H01J37/32412; H01J37/32422
Claims Analysis
Total Claims: 56
Claim 1
Independent Claim
105 words
An ion implantation apparatus comprising: a container for enclosing an object to be implanted; plasma generator means for generating a plasma which surrounds the object in the container; and a pulse modulator for applying electrical pulses to the object which cause ions to be accelerated from the plasma toward and be implanted into the object, the pulse modulator including: power source means for generating an electrical potential; capacitor means connected in circuit with the power source means for charging therefrom; and plasma switch means connected in circuit for causing the capacitor means to periodically discharge into and thereby apply said electrical pulses to the object.
Claim 2
Dependent Claim
19 words
An apparatus as in claim 1, in which the plasma switch means comprises a cold cathode, crossed-magnetic-field modulator switch.
Claim 3
Dependent Claim
39 words
An apparatus as in claim 1, in which: the capacitor means is connected in parallel circuit with the power source means; and the plasma switch means is connected in series circuit with the object across the power source means.
Claim 4
Dependent Claim
30 words
An apparatus as in claim 1, in which the plasma switch means is constructed to periodically connect a negatively charged end of the capacitor means in circuit to the object.
Claim 5
Dependent Claim
43 words
An apparatus as in claim 4, in which the plasma switch means comprises a cold cathode, crossed-magnetic-field modulator switch having a cathode connected in circuit to the negative end of the power source means, and an anode connected in series to the object.
Claim 6
Dependent Claim
39 words
An apparatus as in claim 1, in which: the plasma switch means is connected in parallel circuit with the power source means; and the capacitor means is connected in series circuit with the object across the plasma switch means.
Claim 7
Dependent Claim
50 words
An apparatus as in claim 6, in which: the plasma switch means is connected in circuit between the positively charged end of the capacitor means and the negative end of the power source means; and the negatively charged end of the capacitor means is connected in circuit to the object.
Claim 8
Dependent Claim
49 words
An apparatus as in claim 7, in which the plasma switch means comprises a cold cathode, crossed-magnetic-field modulator switch having a cathode connected in circuit to the negative end of the power source means and an anode connected in circuit to the positively charged end of the capacitor means.
Claim 9
Dependent Claim
19 words
An apparatus as in claim 8, in which the cathode of the cold cathode, crossed-magnetic-field modulator switch is grounded.
Claim 10
Dependent Claim
18 words
An apparatus as in claim 9, in which the negative end of the power source means is grounded.
Claim 11
Dependent Claim
34 words
An apparatus as in claim 1, further comprising pulse transformer means connected in circuit between the capacitor means and the object for stepping up the voltage of the electrical pulses applied to the object.
Claim 12
Dependent Claim
59 words
An apparatus as in claim 1, further comprising: arc detector means for detecting an imminent arcing condition between the object and the plasma; and arc suppression means responsive to the arc detector means for controlling the plasma switch means to terminate said discharge of the capacitor means into the object in response to detection of said imminent arcing condition.
Claim 13
Dependent Claim
41 words
An apparatus as in claim 12, in which the arc detector means comprises current sensor means for detecting flow of current from the capacitor means into the object above a level which is predetermined to correspond to said imminent arcing condition.
Claim 14
Dependent Claim
52 words
An apparatus as in claim 12, in which: the plasma switch means is connected in circuit to close and thereby cause the capacitor means to discharge into the object; and the arc suppression means is constructed to cause the plasma switch means to open in response to-detection of said imminent arcing condition.
Claim 15
Dependent Claim
19 words
An apparatus as in claim 14, in which the plasma switch means comprises a cold cathode, crossed-magnetic-field modulator switch.
Claim 16
Dependent Claim
123 words
An apparatus as in claim 1, in which: said power source means, capacitor means and plasma switch means are connected in circuit to apply said electrical pulses to the object with a negative polarity; the pulse modulator further comprises: second power source means for generating a second electrical potential; second capacitor means connected in circuit with the second power source means for charging therefrom; and second plasma switch means connected in circuit for causing the capacitor means to periodically discharge into the object and thereby apply second electrical pulses to the object; and the second power source means, second capacitor means and second plasma switch means are connected in circuit to apply the second electrical pulses to the object with a positive polarity.
Claim 17
Dependent Claim
46 words
An apparatus as in claim 16, in which the second power source means, second capacitor means and second plasma switch means are constructed to apply the second electrical pulses having the positive polarity to the object in alternation with said electrical pulses having the negative polarity.
Claim 18
Dependent Claim
25 words
An apparatus as in claim 16, in which the first and second plasma switch means comprise first and second cold cathode, crossed-magnetic-field modulator switches respectively.
Claim 19
Dependent Claim
36 words
An apparatus as in claim 16, in which the first and second plasma switch means each comprise; a plasma switch; and control means for individually controlling the opening and closing times of the respective plasma switch.
Claim 20
Dependent Claim
71 words
A pulse modulator for applying electrical pulses to an object for implantation with ions from a plasma in a plasma source ion implantation apparatus, comprising: power source means for generating an electrical potential; capacitor means connected in circuit with the power source means for charging therefrom; and plasma switch means connected in circuit for causing the capacitor means to periodically discharge into and thereby apply said electrical pulses to the object.
Claim 21
Dependent Claim
20 words
A pulse modulator as in claim 20, in which the plasma switch means comprises a cold cathode, crossed-magnetic-field modulator switch.
Claim 22
Dependent Claim
40 words
A pulse modulator as in claim 20, in which: the capacitor means is connected in parallel circuit with the power source means; and the plasma switch means is connected in series circuit with the object across the power source means.
Claim 23
Dependent Claim
31 words
A pulse modulator as in claim 20, in which the plasma switch means is constructed to periodically connect a negatively charged end of the capacitor means in circuit to the object.
Claim 24
Dependent Claim
44 words
A pulse modulator as in claim 23, in which the plasma switch means comprises a cold cathode, crossed-magnetic-field modulator switch having a cathode connected in circuit to the negative end of the power source means, and an anode connected in series to the object.
Claim 25
Dependent Claim
40 words
A pulse modulator as in claim 20, in which: the plasma switch means is connected in parallel circuit with the power source means; and the capacitor means is connected in series circuit with the object across the plasma switch means.
Claim 26
Dependent Claim
51 words
A pulse modulator as in claim 25, in which: the plasma switch means is connected in circuit between the positively charged end of the capacitor means and the negative end of the power source means; and the negatively charged end of the capacitor means is connected in circuit to the object.
Claim 27
Dependent Claim
50 words
A pulse modulator as in claim 26, in which the plasma switch means comprises a cold cathode, crossed-magnetic-field modulator switch having a cathode connected in circuit to the negative end of the power source means and an anode connected in circuit to the positively charged end of the capacitor means.
Claim 28
Dependent Claim
20 words
A pulse modulator as in claim 27, in which the cathode of the cold cathode, crossed-magnetic-field modulator switch is grounded.
Claim 29
Dependent Claim
19 words
A pulse modulator as in claim 28, in which the negative end of the power source means is grounded.
Claim 30
Dependent Claim
35 words
A pulse modulator as in claim 20, further comprising pulse transformer means connected in circuit between the capacitor means and the object for stepping up the voltage of the electrical pulses applied to the object.
Claim 31
Dependent Claim
60 words
A pulse modulator as in claim 20, further comprising: arc detector means for detecting an imminent arcing condition between the object and the plasma; and arc suppression means responsive to the arc detector means for controlling the plasma switch means to terminate said discharge of the capacitor means into the object in response to detection of said imminent arcing condition.
Claim 32
Dependent Claim
42 words
A pulse modulator as in claim 31, in which the arc detector means comprises current sensor means for detecting flow of current from the capacitor means into the object above a level which is predetermined to correspond to said imminent arcing condition.
Claim 33
Dependent Claim
54 words
A pulse modulator as in claim 31, in which: the plasma switch means is connected in circuit to close and thereby cause the capacitor means to discharge into the object; and the arc suppression means is constructed to cause the plasma switch means to open in response to detection of said imminent arcing condition.
Claim 34
Dependent Claim
20 words
A pulse modulator as in claim 33, in which the plasma switch means comprises a cold cathode, crossed-magnetic-field modulator switch.
Claim 35
Dependent Claim
124 words
A pulse modulator as in claim 20, in which: said power source means, capacitor means and plasma switch means are connected in circuit to apply said electrical pulses to the object with a negative polarity; the pulse modulator further comprises: second power source means for generating a second electrical potential; second capacitor means connected in circuit with the second power source means for charging therefrom; and second plasma switch means connected in circuit for causing the capacitor means to periodically discharge into the object and thereby apply second electrical pulses to the object; and the second power source means, second capacitor means and second plasma switch means are connected in circuit to apply the second electrical pulses to the object with a positive polarity.
Claim 36
Dependent Claim
47 words
A pulse modulator as in claim 35, in which the second power source means, second capacitor means and second plasma switch means are constructed to apply the second electrical pulses having the positive polarity to the object in alternation with said electrical pulses having the negative polarity.
Claim 37
Dependent Claim
26 words
A pulse modulator as in claim 35, in which the first and second plasma switch means comprise first and second cold cathode, crossed-magnetic-field modulator switches respectively.
Claim 38
Dependent Claim
37 words
A pulse modulator as in claim 35, in which the first and second plasma switch means each comprise; a plasma switch; and control means for individually controlling the opening and closing times of the respective plasma switch.
Claim 39
Dependent Claim
91 words
A bipolar pulse modulator for individually applying negative and positive electrical pulses to an object for implantation with ions from a plasma in a plasma source ion implantation apparatus, comprising: negative power source means; first plasma switch means connected in circuit for periodically electrically connecting the negative power source means to the object; positive power source means; and second plasma switch means connected in circuit for periodically electrically connecting the positive power source means to the object during periods when the negative power source means is not connected to the object.
Claim 40
Dependent Claim
27 words
A bipolar pulse modulator as in claim 39, in which the first and second plasma switch means comprise first and second cold cathode, crossed-magnetic-field modulator switches respectively.
Claim 41
Dependent Claim
37 words
A pulse modulator as in claim 39, in which the first and second plasma switch means each comprise; a plasma switch; and control means for individually controlling the opening and closing times of the respective plasma switch.
Claim 42
Dependent Claim
53 words
A bipolar pulse modulator as in claim 39, in which: the negative and positive power source means comprise first and second capacitor means respectively; and the first and second plasma switch means are connected in circuit to close and thereby cause the first and second capacitor means respectively to discharge into the object.
Claim 43
Dependent Claim
79 words
A bipolar pulse modulator as in claim 39, in which: the first plasma switch means comprises a first cold cathode, crossed-magnetic-field modulator switch having a cathode connected in circuit to the negative power source means and an anode connected in circuit to the object; and the second plasma switch means comprises a second cold cathode, crossed-magnetic-field modulator switch having an anode connected in circuit to the positive power source means and a cathode connected in circuit to the object.
Claim 44
Dependent Claim
44 words
A bipolar pulse modulator as in claim 39, further comprising pulse transformer means connected in circuit between the negative and positive power source means and the object for stepping up the voltage of the negative and positive electrical pulses applied to the object respectively.
Claim 45
Dependent Claim
66 words
A bipolar pulse modulator as in claim 39, further comprising: arc detector means for detecting an imminent arcing condition between the object and the plasma; and arc suppression means responsive to the arc detector means for controlling the first and second plasma switch means to terminate application of the negative and positive electrical pulses to the object in response to detection of said imminent arcing condition.
Claim 46
Dependent Claim
34 words
A bipolar pulse modulator as in claim 39, further comprising control means for controlling the first and second plasma switch means to alternately connect the negative and positive power source means to the object.
Claim 47
Dependent Claim
89 words
A bipolar pulse modulator for individually applying negative and positive electrical pulses to an object for implantation with ions from a plasma in a plasma source ion implantation apparatus, comprising: negative power source means; first switch means connected in circuit for periodically electrically connecting the negative power source means to the object; positive power source means; and second switch means connected in circuit for periodically electrically connecting the positive power source means to the object during periods when the negative power source means is not connected to the object.
Claim 48
Dependent Claim
24 words
A bipolar pulse modulator as in claim 47, in which the first and second switch means comprise first and second vacuum tube switches respectively.
Claim 49
Dependent Claim
38 words
A pulse modulator as in claim 47, in which the first and second switch means each comprise; a vacuum tube switch; and control means for individually controlling the opening and closing times of the respective vacuum tube switch.
Claim 50
Dependent Claim
52 words
A bipolar pulse modulator as in claim 47, in which: the negative and positive power source means comprise first and second capacitor means respectively; and the first and second switch means are connected in circuit to close and thereby cause the first and second capacitor means respectively to discharge into the object.
Claim 51
Dependent Claim
73 words
A bipolar pulse modulator as in claim 47, in which: the first switch means comprises a first vacuum tube switch having a cathode connected in circuit to the negative power source means and an anode connected in circuit to the object; and the second switch means comprises a second vacuum tube switch having an anode connected in circuit to the positive power source means and a cathode connected in circuit to the object.
Claim 52
Dependent Claim
44 words
A bipolar pulse modulator as in claim 47, further comprising pulse transformer means connected in circuit between the negative and positive power source means and the object for stepping up the voltage of the negative and positive electrical pulses applied to the object respectively.
Claim 53
Dependent Claim
33 words
A bipolar pulse modulator as in claim 47, further comprising control means for controlling the first and second switch means to alternately connect the negative and positive power source means to the object.
Claim 54
Independent Claim
33 words
A method of applying electrical pulses to an object for implantation with ions from a plasma in a plasma source ion implantation apparatus, comprising alternatingly applying positive and negative pulses to the object.
Claim 55
Dependent Claim
27 words
A method as in claim 54, comprising applying the negative pulses having a waveform selected to cause ions from the plasma to be implanted into the object.
Claim 56
Dependent Claim
21 words
A method as in claim 55, comprising applying the positive pulses having a waveform selected to cause generation of the plasma.
References Cited (Backward Citations)
No citation records indexed.
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