Thermoelectric semiconductor material and method of manufacturing same

• US 6,222,242 B1
• Filed: 07/26/1999
• Issued: 04/24/2001
• Est. Priority Date: 07/27/1998
• Status: Expired due to Term

• Current Assignee: Komatsu Ltd.
• Original Assignee: Komatsu Ltd.
• Inventors: Konishi, Akio, Fukuda, Katsushi
• Primary Examiner(s): Clark, Sheila V.
• Application Number:
  US09/361,202
• Time in Patent Office: 638 Days
• Field of Search: 257/467, 257/930, 136/236, 136/203, 136/239, 136/240
• US Class Current: 257/467
• CPC Class Codes: B22F 2998/10 Processes characterised by the sequence of their steps
• CPC Class Codes: B22F 3/105 by using electric current other than for infrared radiant energy, laser radiation or plasma B22F3/11 takes precedence; by ultrasonic bonding B22F3/115 takes precedence
• CPC Class Codes: B22F 9/04 starting from solid material, e.g. by crushing, grinding or milling C22C1/1084 takes precedence; crushing, grinding or milling, in general, see the relevant subclasses, e.g. B02C
• CPC Class Codes: C22C 38/42 with copper
• CPC Class Codes: C22C 38/58 with more than 1.5% by weight of manganese
• CPC Class Codes: C22C 38/60 containing lead, selenium, tellurium, or antimony, or more than 0.04% by weight of sulfur
• CPC Class Codes: C23G 1/08 Iron or steel
• CPC Class Codes: H10N 10/01 Manufacture or treatment
• CPC Class Codes: H10N 10/852 comprising tellurium, selenium or sulfur
• CPC Class Codes: Y10S 257/93 Thermoelectric, e.g. peltier effect cooling

Abstract

The present invention provides a novel thermoelectric semiconductor material having excellent thermoelectric property which is not lowered like a conventional PbTe-based or PbSnTe-based semiconductor material even if a strength is improved by sintering. The thermoelectric semiconductor material of the invention is characterized by having chemical formula AB₂X₄ (where, A is a simple substance or mixture of Pb, Sn and Ge (IV family elements), B is a simple substance or mixture of Bi and Sb (V family elements), and X is a simple substance or mixture of Te and Se (VI family elements). In this case, a spark plasma sintering device is used to apply a pulsed current through the powder material to cause an electrical discharge among particles of the powder to synthesize the compound AB₂X₄ having a uniform structure.

And, the invention synthesizes a compound, which is to be a thermoelectric semiconductor material, so to have a uniform structure.

Using a spark plasma sintering device, a pulsed current is applied to the powder material to cause an electrical discharge among particles of the powder to synthesize compound PbBi₂Te₄ having a uniform structure.

Claims

1. A thermoelectric semiconductor material, characterized by having chemical formula AB₂X₄ (where, A is a simple substance or mixture of Pb, Sn and Ge (IV family elements), B is a simple substance or mixture of Bi and Sb (V family elements), and X is a simple substance or mixture of Te and Se (VI family elements)).

2. A thermoelectric semiconductor material, characterized by having chemical formula Bi₁₋

xSb_xTe₁ (where, 0≦

x≦

1).

3. A thermoelectric semiconductor material, characterized by having chemical formula A_yB₁₋

yX₁ (where, 0≦

y≦

0.25, A is a simple substance or mixture of Pb, Sn and Ge (IV family elements), B is a simple substance or mixture of Bi and Sb (V family elements), and X is a simple substance or mixture of Te and Se (VI family elements)).