programmable circuit having a carbon nanotube

Abstract

A semiconductor device comprising a programming circuit that includes an active device on or in a substrate and a programmable electronic component on the substrate. The programmable electronic component includes at least one carbon nanotube having a segment with an adjusted diameter. The programmable electronic component has a value that depends upon the adjusted diameter. The programming circuit also includes interconnects that couple the active device to the programmable electronic component. The active device is configured to control a current transmitted to the programmable electronic component.

1 . A semiconductor device, comprising:
 a programming circuit, including:
 an active device located on or in a substrate; 
 a programmable electronic component on said substrate, wherein said programmable electronic component includes at least one carbon nanotube having a segment with an adjusted diameter; and 
 interconnects that couple said active device to said programmable electronic component, wherein said active device is configured to control a current transmitted to said programmable electronic component and said programmable electronic component has a value that depends upon said adjusted diameter. 
   
   
   
       2 . The device of  claim 1 , wherein said programmable electronic component is configured as a fusible link, wherein said segment is configured to open when said current, equal to a predefined level, is transmitted through said carbon nanotube, and said value is thereby configured to equal a zero or nonzero current depending on whether said segment is opened or not opened, respectively. 
   
   
       3 . The device of  claim 1 , wherein said programmable electronic component is configured as a capacitor with said carbon nanotube being capacitively coupled to a conductive body such that a distance between said segment and said conductive body is configured to change as a function of said adjusted diameter, and said value is configured to be equal to a capacitance. 
   
   
       4 . The device of  claim 3 , wherein said conductive body comprises a second carbon nanotube. 
   
   
       5 . The device of  claim 3 , wherein said distance ranges from about 30 to 43 nm. 
   
   
       6 . The device of  claim 3 , wherein said adjusted diameter ranges from about 3 to 30 nm. 
   
   
       7 . The device of  claim 3 , wherein said programming circuit further includes:
 an inverter and a comparator, wherein said programmable electronic component is connected to an output of said inverter; and said comparator has a first input comprising a reference signal and a second input comprising an output of said programmable electronic component, and wherein a programming output of said comparator depends upon said value.   
   
   
       8 . The device of  claim 7 , wherein said reference signal comprises a voltage or a clock signal. 
   
   
       9 . The device of  claim 7 , wherein said programming output of said comparator comprises a tripping time of said comparator, said tripping time depending upon said discrete capacitance. 
   
   
       10 . The device of  claim 7 , further including one or more calibration circuits, wherein each of said calibration circuits includes a second inverter whose output is coupled to the input of a known capacitance, and an output of said known capacitance is coupled to a second comparator, wherein said one or more calibration circuits are coupled to said programming circuit to thereby determine said capacitance. 
   
   
       11 . The device of  claim 7 , wherein said value is configured to trim an oscillator of said device, trim a voltage of said device, or to provide a unique identification code for said device. 
   
   
       12 . A semiconductor device, comprising:
 a programming circuit, including:
 transistors located on or in a substrate; 
 a fusible link on said substrate that includes at least one carbon nanotube having a segment with an adjusted diameter; and 
 interconnects that couple said transistors to said programmable electronic component, 
   wherein said transistors are configured to control a current transmitted to said fusible link such that said segment is configured to open when said current, equal to a predefined level, is transmitted through said at least one carbon nanotube, and wherein said fusible link thereby has a value that depends upon said adjusted diameter, said value is being configured to equal a zero or nonzero current depending on whether said segment is opened or not opened, respectively.   
   
   
       13 . A semiconductor device, comprising:
 a programming circuit, including:
 transistors located on or in a substrate; 
 a capacitor on said substrate that includes:
 at least one carbon nanotube having a segment with an adjusted diameter; and 
 a conductive body capacitively coupled to said carbon nanotube, a distance between said segment and said conductive body is configured to change as a function of said adjusted diameter; and 
 
 it interconnects that couple said transistors to said capacitor, 
   wherein said transistors are configured to control a current transmitted to said capacitor, and said capacitor has a value that depends upon said adjusted diameter, said value configured to be equal to a capacitance.   
   
   
       14 . A method of manufacturing a semiconductor device, comprising:
 fabricating a programming circuit, including:
 forming an active device on or in a substrate; 
 forming a programmable electronic component, including depositing a carbon nanotube on said substrate, wherein said carbon nanotube has a segment with an adjustable diameter, and said programmable electronic component has a value that depends upon said adjustable diameter; and 
 forming interconnects that couple said active device to said programmable electronic component. 
   
   
   
       15 . The method of  claim 14 , further includes adjusting said diameter by opening said segment, including transmitting a predefined current through said carbon nanotube, thereby adjusting said value to a zero current. 
   
   
       16 . The method of  claim 14 , further including adjusting said diameter by irradiating said segment with an electron beam, thereby adjusting said value to a predefined capacitance. 
   
   
       17 . The method of  claim 15 , wherein said segment is irradiated with an electron beam to adjust said diameter before transmitting said predefined current. 
   
   
       18 . The method of  claim 16 , further including applying a potential to said segment during said irradiating. 
   
   
       19 . The method of  claim 14 , wherein forming said programmable electronic component includes forming a conductive body close to said carbon nanotube, thereby establishing a capacitance between said carbon nanotube and said conductive body. 
   
   
       20 . The method of  claim 19 , wherein forming said conductive body includes depositing a conductive layer on said substrate and patterning said conductive layer. 
   
   
       21 . The method of  claim 19 , wherein depositing said conductive body includes depositing a second carbon nanotube on said substrate.