Heat dissipation structure of SOI field effect transistor
The present invention discloses a heat dissipation structure for a SOI field effect transistor having a schottky source/drain, which relates to a field of microelectronics. The heat dissipation structure includes two holes connected with a drain terminal or with both a source terminal and a drain terminal, which are filled with an N-type material with high thermoelectric coefficient and a P-type material with high thermoelectric coefficient respectively. A metal wire for the N-type material with high thermoelectric coefficient in the vicinity of the drain terminal is applied a high potential with respect to the drain terminal, and a metal wire for the P-type material with high thermoelectric coefficient in the vicinity of the drain terminal is applied a low potential with respect to the drain terminal. A metal wire for the N-type material with high thermoelectric coefficient in the vicinity of the source terminal is applied a high potential with respect to the source terminal, and a metal wire for the P-type material in the vicinity of the source terminal is applied a lower potential with respect to the source terminal. By way of a Peltier effect, in the present invention heat can be absorbed at a contact portion between the thermoelectric material and the source/drain, and at the same time dissipated at a connection portion between the thermoelectric material and a bottom electrode metal, so that the heat generated in an active region of the device is effectively transferred to the substrate and dissipated through a heat sink.
1. A heat dissipation structure for a SOI field effect transistor having a schottky source/drain, wherein, in a SOI substrate in the vicinity of a drain terminal of the SOI field effect transistor having the schottky source/drain, two holes are formed, in which an N-type material with high thermoelectric coefficient and a P-type material with high thermoelectric coefficient are filled respectively; the N-type material with high thermoelectric coefficient and the P-type material with high thermoelectric coefficient are connected with the drain terminal of the SOI field effect transistor in manner of ohmic contact; a first metal wire for the N-type material with high thermoelectric coefficient is applied a high potential with respect to the drain terminal, and a second metal wire for the P-type material with high thermoelectric coefficient is applied a low potential with respect to the drain terminal; and when the device does not operate or does not need heat dissipation, potentials of the first and second metal wires connected to the P-type and N-type material with high thermoelectric coefficient are both equal to a drain voltage.
2. The heat dissipation structure according to claim 1 , wherein the materials with high thermoelectric coefficient are common compound semiconductor from V-VI group such as Bi 2 Te 3 and Bi 2 Sb, a nano material with high thermoelectric coefficient or other material with high thermoelectric coefficient.
3. The heat dissipation structure according to claim 1 , wherein the N-type material with high thermoelectric coefficient and the P-type material with high thermoelectric coefficient are both heavily doped and have identical resistance value.
4. The heat dissipation structure according to claim 1 , wherein, with each of the source terminal and the drain terminal of the field effect transistor having a length of 0.4 μm and a width of 0.8 μm, a length of each of the holes are less than 0.4 μm, and a width of each of the holes are less than 0.25 μm, where a size of each of the holes has a minimum size determined by a photolithography process.
5. A heat dissipation structure for a SOI field effect transistor having a schottky source/drain, wherein in a first SOI substrate in the vicinity of a drain terminal of the SOI field effect transistor having the schottky source/drain, two holes are formed, in which an N-type material with high thermoelectric coefficient and a P-type material with high thermoelectric coefficient are filled, respectively; the N-type material with high thermoelectric coefficient and the P-type material with high thermoelectric coefficient are connected with the drain terminal of the SOI field effect transistor in manner of ohmic contact; in a second SOI substrate in the vicinity of a source terminal of the SOI field effect transistor having the schottky source/drain, two holes are formed, in which an N-type material with high thermoelectric coefficient and a P-type material with high thermoelectric coefficient are filled, respectively; the N-type material with high thermoelectric coefficient and the P-type material with high thermoelectric coefficient are connected with the source terminal of the SOI field effect transistor in manner of ohmic contact; a first metal wire for the N-type material with high thermoelectric coefficient in the vicinity of the drain terminal is applied a high potential with respect to the drain terminal, and a second metal wire for the P-type material with high thermoelectric coefficient in the vicinity of the drain terminal is applied a low potential with respect to the drain terminal; a third metal wire for the N-type material with high thermoelectric coefficient in the vicinity of the source terminal is applied a high potential with respect to the source terminal, and a fourth metal wire for the P-type material with high thermoelectric coefficient in the vicinity of the source terminal is applied a low potential with respect to the source terminal; when the device does not operate or does not need heat dissipation, potentials of third and fourth metal wires connected to the N-type and P-type materials with high thermoelectric coefficient in the vicinity of the source terminal are both equal to a source voltage; and potentials of first and second metal wires connected to the N-type and P-type materials with high thermoelectric coefficient in the vicinity of the drain terminal are both equal to a drain voltage.
6. The heat dissipation structure according to claim 5 , wherein the materials with high thermoelectric coefficient are common compound semiconductor from V-VI group such as Bi 2 Te 3 and Bi 2 Sb, a nano material with high thermoelectric coefficient or other material with high thermoelectric coefficient.
7. The heat dissipation structure according to claim 5 , wherein the N-type material with high thermoelectric coefficient and the P-type material with high thermoelectric coefficient are both heavily doped and have identical resistance value.
8. The heat dissipation structure according to claim 5 , wherein, with each of the source terminal and the drain terminal of the field effect transistor having a length of 0.4 μm and a width of 0.8 μm, a length of each of the holes are less than 0.4 μm, and a width of each of the holes are less than 0.25 μm, where a size of each of the holes has a minimum size determined by a photolithography process.
9. The heat dissipation structure according to claim 8 , wherein, a distance between the two holes at the drain terminal or the source terminal is more than 0.3 μm.
10. The heat dissipation structure according to claim 8 , wherein, a distance between the two holes at the drain terminal or the source terminal is more than 0.3 μm.