Doped elongated semiconductors, growing such semiconductors, devices including such semiconductors and fabricating such devices

Abstract

A bulk-doped semiconductor that is at least one of the following: a single crystal, an elongated and bulk-doped semiconductor that, at any point along its longitudinal axis, has a largest cross-sectional dimension less than 500 nanometers, and a free-standing and bulk-doped semiconductor with at least one portion having a smallest width of less than 500 nanometers. Such a semiconductor may comprise an interior core comprising a first semiconductor; and an exterior shell comprising a different material than the first semiconductor. Such a semiconductor may be elongated and may have, at any point along a longitudinal section of such a semiconductor, a ratio of the length of the section to a longest width is greater than 4:1, or greater than 10:1, or greater than 100:1, or even greater than 1000:1. At least one portion of such a semiconductor may a smallest width of less than 200 nanometers, or less than 150 nanometers, or less than 100 nanometers, or less than 80 nanometers, or less than 70 nanometers, or less than 60 nanometers, or less than 40 nanometers, or less than 20 nanometers, or less than 10 nanometers, or even less than 5 nanometers. Such a semiconductor may be a single crystal and may be free-standing. Such a semiconductor may be either lightly n-doped, heavily n-doped, lightly p-doped or heavily p-doped. Such a semiconductor may be doped during growth. Such a semiconductor may be part of a device, which may include any of a variety of devices and combinations thereof, and a variety of assembling techniques may be used to fabricate devices from such a semiconductor. Two or more of such a semiconductors, including an array of such semiconductors, may be combined to form devices, for example, to form a crossed p-n junction of a device. Such devices at certain sizes may exhibit quantum confinement and other quantum phenomena, and the wavelength of light emitted from one or more of such semiconductors may be controlled by selecting a width of such semiconductors. Such semiconductors and device made therefrom may be used for a variety of applications.

1 . A device comprising at least one doped semiconductor, wherein the at least one doped semiconductor is at least one of the following: a single crystal, an elongated and bulk-doped semiconductor that, at any point along its longitudinal axis, has a largest cross-sectional dimension less than 500 nanometers, and a free-standing and bulk-doped semiconductor with at least one portion having a smallest width of less than 500 nanometers, wherein the device is able to sense light.  
   
   
       2 . The device of  claim 1 , wherein the device comprises at least two doped semiconductors, wherein both of the at least two doped semiconductors is at least one of the following: a single crystal, an elongated and bulk-doped semiconductor that, at any point along its longitudinal axis, has a largest cross-sectional dimension less than 500 nanometers, and a free-standing and bulk-doped semiconductor with at least one portion having a smallest width of less than 500 nanometers, and wherein a first of the at least two doped semiconductors exhibits quantum confinement and a second of the at least two doped semiconductor manipulates the quantum confinement of the first.  
   
   
       3 . The device of  claim 1 , wherein the device comprises at least two doped semiconductor, wherein both of the at least two doped semiconductors is at least one of the following: a single crystal, an elongated and bulk-doped semiconductor that, at any point along its longitudinal axis, has a largest cross-sectional dimension less than 500 nanometers, and a free-standing and bulk-doped semiconductor with at least one portion having a smallest width of less than 500 nanometers.  
   
   
       4 . The device of  claim 3 , wherein the at least two bulk-doped semiconductors are in physical contact with each other.  
   
   
       5 . The device of  claim 4 , wherein a first of the at least two bulk-doped semiconductors is of a first conductivity type, and a second of the at least two bulk-doped semiconductors is of a second conductivity type.  
   
   
       6 . The device of  claim 5 , wherein the first conductivity type is n-type, and the second type of conductivity type is p-type.  
   
   
       7 . The device of  claim 6 , wherein the at least two bulk-doped semiconductors form a p-n junction.  
   
   
       8 . The device of  claim 1 , wherein the at least one semiconductor is free-standing.  
   
   
       9 . The device of  claim 1 , wherein the at least one semiconductor is elongated.  
   
   
       10 . The device of  claim 1 , wherein the at least one semiconductor comprises a single crystal.  
   
   
       11 . The device of  claim 1 , wherein the at least one semiconductor comprises: 
 an interior core comprising a first semiconductor; and    an exterior shell comprising a different material than the first semiconductor.    
   
   
       12 . The device of  claim 1 , wherein the at least one doped semiconductor is contained within a transistor.  
   
   
       13 . The device of  claim 12 , wherein the transistor is a bipolar junction transistor.  
   
   
       14 . The device of  claim 12 , wherein the transistor comprises a field effect transistor.  
   
   
       15 . The device of  claim 1 , wherein the device is a single photon detector.  
   
   
       16 . A light-sensing device, comprising: 
 a field effect transistor comprising first and second electrodes and a semiconductor nanoscale wire electrically coupling the first and second electrodes, the nanowire able to produce a signal in response to an incident single photon.    
   
   
       17 . The light-sensing device of  claim 16 , wherein the nanowire comprises at least one portion having a smallest width of less than 500 nanometers.  
   
   
       18 . A light-sensing device comprising a plurality of the field effect transistors of  claim 16 , wherein each of the nanoscale wires of the light-sensing device is taken from a population of nanoscale wires having a variation in average diameter of less than 20% relative to each other, the population of nanoscale wires being grown catalytically from a population of catalyst particles having a variation in diameter of less than 20%, wherein the diameter of each of the nanoscale wires is determined by the diameter of the catalyst particle from which the nanoscale wire is grown.  
   
   
       19 . The light-sensing device of  claim 18 , and wherein each of the nanoscale wires is doped during growth of the nanoscale wire from the catalyst particle.  
   
   
       20 . The light-sensing device of  claim 16 , wherein the smallest dimension is less than about 20 nm.  
   
   
       21 . The light-sensing device of  claim 16 , wherein the smallest dimension is less than is about 10 nm.  
   
   
       22 . The light-sensing device of  claim 16 , wherein the nanoscale wire has an aspect ratio of length to thickness of at least about 10:1.  
   
   
       23 . The light-sensing device of  claim 16 , wherein the nanoscale wire has an aspect ratio of length to thickness of at least about 100:1.  
   
   
       24 . The light-sensing device of  claim 16 , wherein the nanoscale wire is a single crystal.