Static field-induced semiconductor devices

Claim 2

Claim 2. The field effect transistor (10;50;80;110;140;170;232,234;272,274;310) of Claim 1, further characterized by: the channel region (20;55;98;126;160;184;265,266;304,306;328,330) being formed of a substantially intrinsic amorphous semiconductor material; and the built-in charge of the field inducing body (16,26;66,68,70;94;124;158;192;246,248;288,292;312) shifting the Fermi level of the channel region to make it either an n-type or a p-type semiconductor.

Claim 3

Claim 3. The field effect transistor (10;50;80;110;140;170;232,234;272,274;310) of Claim 1, further characterized by the built-in charge of the field inducing body (16,26;66,68,70;94;124;158;192;246,248;288,292;312) shifting the Fermi level of the channel region (20;55;98;126;160;184;265,266;304,306;328,330) so less voltage has to be applied to the gate (30;60,78;82;112;154;188;254,256;278,302;324,326) to switch the channel region from a substantially non-conducting to a substantially conducting state.

Claim 4

Claim 4. The field effect transistor (10;50;80;110;140;170;232,234;272,274;310) of Claim 1, further characterized by the built-in charge of the field inducing body (16,26;66,68,70;94;124;158;192;246,248;288,292;312) shifting the Fermi level of the channel region (20;55;98;126;160;184;265,266;304,306;328,330) so the channel region becomes substantially conducting in the absence of any voltage app1ied to the gate (30;60,78;82;112;154;188;254,256;278,302;324,326), and so a voltage must be applied to the gate to make the channel region substantially non-conducting.

Claim 5

Claim 5. The field effect transistor (10;50;80;110;140;170;232,234;272,274;310) of Claim 1, further characterized by having a body (18;72,74;92;118;148;182;238;282,294;316) of amorphous semiconductor material in which the channel region (20;55;98;126;160;184;265,266;304,306;328,330) is located, and by the field inducing body (16,26;66,68,70;94;124;158;192;246,248;288,292;312) being in contact with said body of amorphous semiconductor material.

Claim 6

Claim 6. The field effect transistor (10;50;80;110;140;170;232,234;272,274;310) of Claim 5, further characterized by: the body (18;72,74;92;118;148;182;238;282,294;316) of amorphous semiconductor material and the field inducing body (16,26;66,68,70;94;124;158;192;246,248;288,292;312) each being made of layers of deposited material; one of said two layers being deposited in contact with the other, and the built-in charge of the field inducing layer being formed in the creation of such layers.

Claim 7

Claim 7. The field effect transistor (10;50;80;110;140;170;232,234;272,274;310) of Claim 6, further characterized by said field inducing layer (16,26;66,68,70;94;124;158;192;246,248;288,292;312) being formed of an intrinsically charging material of the type which forms independently of the addition to such material of any impurity doping atoms, a built-in charge when a layer of such intrinsic material and the layer (18;72,74;92;118;148;182;238;282,294;316) of amorphous semiconductor material are deposited, one in contact with the other.

Claim 8

Claim 8. The field effect transistor (10;50;80;110;140;170;232,234;272,274;310) of Claim 7, further characterized by the intrinsically charging material (16,26;66,68,70;94;124;158;192;246,248;288,292;312) being an alloy of amorphous silicon including a member chosen from the group consisting essentially of: carbon, hydrogen, nitrogen, fluorine and mixtures thereof.

Claim 9

Claim 9. The field effect transistor (10;50;80;110;140;170;232,234;272,274;310) of Claim 8, further characterized by the intrinsically charging material (16,26;66,68,70;94;124;158;192;246,248;288,292;312) being an amorphous silicon carbide alloy having the general formula amorphous Si:C:H.

Claim 10

Claim 10. The field effect transistor (10;50;80;110;140;170;232,234;272,274;310) of Claim 8, further characterized by the intrinsically charging material (16,26;66,68,70;94;124;158;192;246,248;288,292;312) being an amorphous silicon nitride alloy having the general formula amorphous Si:N:H.

Claim 11

Claim 11. The field effect transistor (10;50;80;110;140;170;232,234;272,274;310) of Claim 7, further characterized by the field inducing layer (16,26;66,68,70;94;124;158;192;246,248;288,292;312) having impurity doping atoms added to it so that the built-in charge formed on the field inducing layer has in addition to charged formed independently of the addition of such impurity doping atoms, a significant charge resulting from charge transfer between the field inducing layer and the layer (18;72,74;92;118;148;182;238;282,294;316) of amorphous semiconductor material caused by the presence of such impurity doping atoms.

Claim 12

Claim 12. The field effect transistor (10;50;80;110;140;170;232,234;272,274;310) of Claim 6, further characterized by the field inducing body (16,26;66,68,70;94;124;158;192;246,248;288,292;312) being made of a material which is an electrical insulator.

Claim 13

Claim 13. The field effect transistor (10;50;80;110;140;170;232,234;272,274;310) of Claim 6, further characterized by the field inducing body (16,26;66,68,70;94;124;158;192;246,248;288,292;312) being formed of a layer between 10 and 100 Angstroms thick.

Claim 14

Claim 14. The field effect transistor (10;50;140;170;232;234) of Claim 5, further characterized by: the transistor including a gate insulator (28;64,76;152;186;250,252) located between the channel region (20;55,160;184;265,266) and the gate (30;60,78;154;188;254,256); and the field inducing body (26;66,70;158;192;246,248) being formed in a layer located between the channel region and the gate insulator.

Claim 15

Claim 15. The field effect transistor (10;50;80;110;272,274;310) of Claim 5, further characterized by: the transistor including a layer (28;64,76;86;116;280,300;322) of gate insulator located between the channel region (20;55;98;126;304,306;328,330) and the gate (30;60,78;82;112;278;302;324,326), and further including a layer (18;52,54;92;118;282;294;316) of amorphous semiconductor material in which the channel region is located; and the field inducing body (16;68;94;124;288,292;312) being formed in a layer located on the opposite side of the layer of amorphous semiconductor material from the layer of gate insulator.

Claim 16

Claim 16. The field effect transistor (10;50;80) of Claim 15, further characterized by including a second field inducing body (26;66,70;100) in the form of a layer, formed with a built-in charge, said second field inducing body being located between the layer (18;52,54;92) of amorphous semiconductor material and the gate insulator (28;64,76;86) so as to be in field effect proximity to the channel region (20;55;98) and thus aid in shifting the Fermi level thereof by means of a field effect rather than by atomic impurity doping.

Claim 17

Claim 17. The field effect transistor (310) of Claim 1, further characterized by: said gate being comprised of a plurality of separate, variably chargeable gate electrodes (324,326), each of which is capable of inducing a change in the conductivity of a corresponding separate portion (328,330) of the channel region located in field effect proximity to it, and said conduction channel (328,330) being formed all the way between the source (318) and drain (320) only when each of the portions of the channel region corresponding to each of the separate gate electrode is conductive.

Claim 18

Claim 18. The field effect transistor (10;50;80;110;140;170;232,234;272,274;310) of Claim 1, further characterized by the channel region (20;55;98;126;160;184;265,266;304,306;328,330) being formed of an amorphous alloy of silicon.

Claim 19

Claim 19. The field effect transistor (10;50;80;110;140;170;232,234;272,274;310) of Claim 1, further characterized by the channel region (20;55;98;126;160;184;265,266;304,306;328,330) being formed of an amorphous alloy of germanium.

Claim 20

Claim 20. The field effect transistor (10;50;80;110;140;170;232,234;272,274;310) of Claim 1, further characterized by the channel region (20;55;98;126;160;184;265,266;304,306;328,330) being formed of an amorphous alloy of silicon and germanium.

Claim 21

Claim 21. The field effect transistor (10;50;80;110;140;170;232,234;272,274;310) of Claim 1 further characterized by: said channel region (20;55;98;126;160;184;265,266;304,306;328,330) being formed in a channel layer (18;72,74;92;118;148;182;238;282,294;316) of deposited thin film of amorphous semiconductor, and including a gate insulator (28;64,76;86;116;152;186;250;252;280,300;322) for electrically insulating the gate (30;60,78;82;112;154;188;254,256;278,302;324,326) from the channel layer.

Claim 22

Claim 22. The thin film field effect transistor (50) of Claim 21 further characterized by: having a plurality of said channel layers (52,54), each having a channel region (55) in which a conductive channel can be formed, and one or more of said field inducing layers (66,68,70), each formed with a built-in charge, located so that each channel layer has at least one field inducing layer in field effect proximity to it so as to shift the Fermi level of the channel region of that layer by means of a field effect rather than by atomic impurity doping; and the plurality of channel layers being arrayed one on top of the other, with a field inducing layer (68) between each adjacent pair of channel layers, to form a multilayered structure comprised of said channel layers and said one or more field inducing layers.

Claim 23

Claim 23. The thin film field effect transistor (80;110) of Claim 21, having a substrate (84;114), further characterized by: the gate (82;112) being formed of conductive material on the substrate; the gate insulator (86;116) being formed in a layer overlying the gate; the source (88;120) and drain (90;121) electrodes being disposed over the gate insulator in non-overlapping relation to each other so as to be separated from each other by a gap; and the channel layer (92;118) being disposed over the gate insulator, extending between the source and drain.

Claim 24

Claim 24. The thin film field effect transistor (80;110) of Claim 23 further characterized by: one of the two layers of deposited materials, either the channel layer (92;118) or the field inducing layer (94,100;124), being deposited in contact with the other; and the built-in charge of the field inducing layer being formed in the creation of such layers.

Claim 25

Claim 25. The thin film field effect transistor (80;110) of Claim 23, further characterized by the gate insulator (86;116) being formed of an oxide which has been annealed after its deposition upon the gate (82;112) and before the deposition of the channel layer (92;118) at a temperature of at least 400 degrees centigrade.

Claim 26

Claim 26. The thin film field effect transistor (110) of Claim 23, further characterized by: the gate (112) having a first non-coplanar surface (128) with respect to the substrate (114); the layer (116) of the gate insulator which overlies the gate having a non-coplanar surface (130) which overlies the first non-coplanar surface of the gate; the channel layer (118) and the conduction channel (126) which can be formed in it extending across a portion of the second non-coplanar surface; and the source (120) and drain (121) being formed on generally opposite sides of the non-coplanar surface (128).

Claim 27

Claim 27. The thin film field effect transistor (140) of Claim 21, further characterized by: the transistor being formed on a substantially horizontal substrate (142) and being comprised of a plurality of substantially horizontal layers (146,148,144) vertically arrayed with respect to the substrate and to each other, including a layer (144) forming the source, a layer (146) forming the drain, and the channel layer (148) between the source and drain layers; at least portions of the edges of the plurality of layers forming a non-coplanar surface (150) with respect to the substrate; the gate insulator (152) overlying at least a portion of the non-coplanar surface; and the gate (154) being placed over the gate insulator. Claim 28. The thin film field effect transistor (140) of Claim 27 further characterized by: one of the two layers of deposited materials, either the channel layer (148) or the field inducing layer (158), being deposited in contact with the other; and the built-in charge of the field inducing layer being formed in the creation of such layers.

Claim 28

Claim 29. The thin film field effect transistor (170) of Claim 21, further characterized by: the transistor being formed on a substantially horizontal substrate (172) and being comprised of a plurality of substantially horizontal layers (174,176,178) vertically arrayed with respect to the substrate and to each other, including a layer (174) forming the source, a layer (176) forming the drain, and an electrically insulating layer (178) between the source and drain layers; at least portions of the edges of the plurality of layers forming a non-coplanar surface (180) with respect to the substrate; the channel layer (182) overlying the non-coplanar surface between, and being in electrical connection with, the source and drain layers so as to be able to form the current conduction channel (184) therebetween; the gate insulator (186) being placed over the channel layer; and the gate (188) being placed over the gate insulator.

Claim 29

Claim 30. The thin film field effect transistor (170) of Claim 29, further characterized by: one of the two layers of deposited material, either the channel layer (182) or the field inducing layer (192) being deposited in contact with the other; and the built-in charge of the field inducing layer being formed in the creation of such layers.

Claim 30

Claim 31. An electronic circuit (200;230;270) of the type having two field effect transistors (202,204;232,234;272,274) each including two current path electrodes, one being a source (206;240,244;284,296) and the other being a drain (208;242;286,298), a channel region (210;265,266;304,306) of amorphous semiconductor material in which a conduction channel can be formed between the source and drain, and a gate (212;254;256;278,302) adapted, in response to an applied voltage, to induce a change in the conductivity of the channel region; of the type having a common input (214;262) and a common output (216;264), with the gates of both transistors responsive to the common input, and one current path electrode of each transistor connected to the common output, and having the other current path electrode of one transistors connected to a relatively positive voltage supply (218;258) and the other current path electrode of the other transistor connected to a relatively negative voltage supply (220;260); and of the type having the channel regions of the two transistors made so that a voltage supplied to the common input which turns one transistor on will turn the other transistor off, said circuit characterized by: a field inducing body (246,248;286,292) of material, in at least one of the two transistors, formed with a built-in charge, in field effect proximity to the channel region of that transistor so as to shift the Fermi level thereof by means of a field effect rather than by atomic impurity doping.

Claim 31

Claim 32. The electronic circuit (200;230;270) of Claim 31, further characterized by the two transistors (202,204;232,234;272,274) being metal-oxide-semiconductor transistors and one of them (204;234;274) being an n-channel transistor and the other (202;232;272) being a p-channel transistor.

Claim 32

Claim 33. The electronic circuit (200;230;270) of Claim 31, further characterized by each of the transistors (202,204;232,234;272,274) comprising: a field inducing body (246,248;286,292) of material, formed with a built-in charge, in field effect proximity to the channel region (210;265,266;304,306) of that transistor so as to shift the Fermi level thereof by means of a field effect rather than by atomic impurity doping.

Claim 33

Claim 34. The electronic circuit (200;230;270) of Claim 33, further characterized by the channel region (210;265,266;304,306) of the at least one transistor (202,204;232,234;272,274) being formed of a substantially intrinsic amorphous semiconductor material and the built-in charge of its associated field inducing body (246,248;286,292) shifting the Fermi level of that channel region so as to make it either an n-type or a p-type semiconductor.

Claim 34

Claim 35. The electronic circuit (200;230;270) of Claim 31, further characterized by the built-in charge of the field inducing body (246,248;286,292) of the at least one transistor (202,204;232,234;272,274) shifting the Fermi level of its associated channel region (210;265,266;304,306) so less voltage has to be applied to the associated gate (212;254;256;278,302) to switch that channel region from a substantially non-conducting to a substantially conducting state.

Claim 35

Claim 36. The electronic circuit (200;230;270) of Claim 31, further characterized by the built-in charge of the field inducing body (246,248;286,292) of the at least one transistor (202,204;232,234;272,274) shifting the Fermi level of its associated channel region (210;265,266;304,306) so that channel region.becomes substantially conducting in the absence of any voltage applied to the associated gate (212;254;256;278,302), and so a voltage must be applied to that gate to make that channel region substantially non-conducting.

Claim 36

Claim 37. The electronic circuit (200;230;270) of Claim 31, further characterized by: the at least one transistor (202,204;232,234;272,274) having a channel layer (238;282,294) formed of amorphous semiconductor material in which the channel region (210;265,266;304,306) is included; the associated field inducing body (246,248;286,292) being formed as a field inducing layer; the channel layer and field inducing layer of the at least one transistor being each made of deposited materials; one of said two layers being deposited in contact with the other; and the built-in charge of the field inducing layer being formed in the creation of such layers.

Claim 37

Claim 38. The electronic circuit (200;230;270) of Claim 37, further characterized by said field inducing layer (246,248;286,292) being formed of an intrinsically charging material of the type which forms, independently of the addition to such material of any impurity doping atoms, a built-in charge when a layer of such intrinsic material and the layer (238;282,294) of amorphous semiconductor material are deposited, one in contact with the other.

Claim 38

Claim 39. The electronic circuit (200;230;270) of Claim 38, further characterized by the intrinsically charging material (246,248;286,292) being an alloy of amorphous silicon including a member chosen from the group consisting essentially of: carbon, hydrogen, nitrogen, fluorine and mixtures thereof.

Claim 39

Claim 40. The electronic circuit (200;230;270) of Claim 39, further characterized by the intrinsically charging material (246,248;286,292) being an amorphous silicon carbide alloy having the general formula amorphous Si:C:H.

Claim 40

Claim 41. The electronic circuit (200;230;270) of Claim 39, further characterized by the intrinsically charging material (246,248;286,292) being an amorphous silicon nitride alloy having the general formula amorphous Si:N:H.

Claim 41

Claim 42. The electronic circuit (200;230;270) of Claim 38, further characterized by the field inducing layer (246,248;286,292) having impurity doping atoms added to it so that the built-in charge includes, in addition to charge formed independently of the addition of such impurity doping atoms, a significant charge resulting from charge transfer between the field inducing layer and the layer (238;282,294) of amorphous semiconductor material caused by the presence of such impurity doping atoms.

Claim 42

Claim 43. The electronic circuit (200;230;270) of Claim 31, further characterized by the field inducing body (246,248;286,292) of the at least one transistor (202,204;232,234;272,274) being made of a material which is an electrical insulator.

Claim 43

Claim 44. The electronic circuit (270) of Claim 31, further including a substrate (276), and further characterized by: both of the two transistors (272,274) being thin film transistors in which the channel region (304,306) is formed of a layer (282,294) of amorphous semiconductor material; the field inducing body (288,292) being formed in a layer; and the layers of the channel regions of the two transistors and of the field inducing body being all disposed one on top of the other above, and substantially parallel to, the substrate. Claim 45. A semiconductor device (340;370;390) characterized by: a first region (342;408)*of material consisting essentially of an amorphous semiconductor material; a first field inducing layer (344;380;394) of material, formed with a built-in charge, in field effect proximity to said first region so as to proximity dope at least a layer of said semiconductor material in said region parallel to the field inducing layer by shifting the Fermi level thereof toward one band edge, either the conduction or valence band edge, by means of a field effect rather than by atomic impurity doping; and a second region (346;410) of material which has its Fermi level positioned further away from said one band edge than that of said material in said first region; and wherein said first and second regions are in contact with each other so as to form a junction which extends in a direction so as to influence the flow of current which lies within, and runs parallel to, said proximity doped layer.

Claim 44

Claim 46. The semiconductor device (340;390) of Claim 45 further characterized by:

Claim 45

said second region (346;410) of material consisting essentially of an amorphous semiconductor material; said device further including a second field inducing layer (348;396) of material, formed with a built-in charge of a polarity opposite that of the built-in charge of said first field inducing body (349;394), in field effect proximity to said second region so as to proximity dope at least a layer of semiconductor material in said second region by shifting the Fermi level thereof toward the band edge opposite the band edge toward which the Fermi level of the first region (342;408) is shifted, said shifting of the Fermi level in said second region by said field inducing body being accomplished by means of a field effect rather than by atomic impurity doping; and said first and second regions being in contact with each other so as to make said junction a p-n junction.

Claim 46

Claim 47. The semiconductor device (390) of Claim 45, further characterized by including a variably chargeable body (406) of material, in field effect proximity to either said first or second region (408) so as to variably alter, by means of a field effect, the amount which the Fermi level in said first or second region is shifted toward or away from said one band edge in the vacinity of said junction.

Claim 47

Claim 48. The semiconductor device (340;370;390) of Claim 45, further characterized by: said device including a single layer of amorphous semiconductor material (342,346;378;402) of which both said first (342;408) and second (346;410) region are part; and said first field inducing layer (344;380;394) being formed in contact with said first region of said layer.