Radiation detector

A semiconductor radiation detector system-comprising:

• a semiconductor material for x-ray or gamma ray detection having a first surface and a second surface, the first surface being opposite from the second surface, the semiconductor material comprising CdZnTe or CdZnTeSe, the semiconductor material effective to absorb radiation and induce a current pulse in response thereto;
• a readout circuit;
• and
• at least one first electrode contact attached to the first surface and at least one second electrode contact attached to the second surface, wherein the first electrode contact and the second electrode contact are conductively connected to the readout circuit and wherein each of the first electrode contact and the second electrode contact comprises aluminum-doped zinc oxide (Al:ZnO) and has a thickness exceeding about 200 nanometers,
• wherein the semiconductor radiation detector with the first electrode contact and the second electrode contact comprising Al:ZnO produces lesser dark current when bias voltage is applied across the first electrode contact and the second electrode contact during radiation detection than if the two electrode contacts comprised gold instead of said Al:ZnO.

A method of making a radiation detector, the method comprising:

• receiving a semiconductor material for x-ray or gamma ray detection having a first surface and a second surface, the first surface being opposite from the second surface, the semiconductor material comprising CdZnTe or CdZnTeSe, the semiconductor material effective to absorb radiation and induce a current pulse in response thereto;
• depositing aluminum-doped zinc oxide (Al:ZnO) as a first electrode contact on the first surface of the semiconductor material;
• and
• depositing aluminum-doped zinc oxide (Al:ZnO) as a second electrode contact on the second surface of the semiconductor material,
• wherein the aluminum-doped zinc oxide (Al:ZnO) on each of the first surface and the second surface has a thickness exceeding about 200 nanometers,
• wherein the semiconductor radiation detector with the first electrode contact and the second electrode contact comprising Al:ZnO produces lesser dark current when bias voltage is applied across the first electrode contact and the second electrode contact during radiation detection than if the two electrode contacts comprised gold instead of said Al:ZnO.

A semiconductor radiation detector, the semiconductor radiation detector comprising:

• a semiconductor material for x-ray or gamma ray detection bounded by a first surface and a second surface, the first surface being opposite from the second surface, the semiconductor material comprising CdZnTe or CdZnTeSe, the semiconductor material effective to absorb radiation and induce a current pulse in response thereto;
• and
• a first electrode contact and a second electrode contact respectively deposited on the first surface and the second surface respectively, each of the first electrode contact and the second electrode contact includes Al:ZnO such that the combination of said semiconductor and said first and second electrode contacts have close thermal expansion coefficients,
• wherein each of said the first electrode contact and the second electrode contact has a thickness exceeding about 200 nanometers and wherein the semiconductor radiation detector with the first electrode contact and the second electrode contact comprising Al:ZnO produces lesser dark current when bias voltage is applied across the first electrode contact and the second electrode contact during radiation detection than if the two electrode contacts comprised gold instead of said Al:ZnO.