Patent ID: 8242436

Claim:
A neutron porosity measurement device, comprising: a cavity configured to receive a neutron source that emits neutrons; a first semiconductor detector located at a first distance from the cavity; a second semiconductor detector located at a second distance larger than the first distance from the cavity, wherein each of the first and the second semiconductor detector includes a semiconductor substrate doped to form a pn junction, and having microstructures of neutron reactive material formed to extend from a first surface inside the semiconductor substrate, and electrodes, one of which is in contact with the first surface of the semiconductor substrate and another one of which is in contact with a second surface of the semiconductor substrate, the second surface being opposite to the first surface, the electrodes being configured to acquire an electrical signal occurring when a neutron is captured inside the semiconductor substrate; and an electronics block located between the first semiconductor detector and the second semiconductor detector and configured to receive the electrical signal from the electrodes, wherein no high power source is included to provide an electric field across the first semiconductor detector and/or to the second semiconductor detector, a space between the first semiconductor detector and the second semiconductor detector, except for the electronics block, being filled with a neutron absorber.