BiHEMT device having a stacked separating layer

US8994069B2 · kind B2 · utility

Assignee

• VISUAL PHOTONICS EXPITAXY CO., LTD · TW

Inventors

• Yu-Chung Chin · Taoyuan, TW
• Chao-Hsing Huang · Taipei, TW

Key dates

• Filing date: Jun 5, 2013
• Grant date: Mar 31, 2015
• Expiry date: Jun 5, 2033

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D62/8503

Abstract

A high electron mobility bipolar transistor including a substrate, a pseudomorphic high electron mobility transistor (pHEMT) sub structure, a sub collector/separating layer and a heterojunction bipolar transistor (HBT) sub structure sequentially stacked from bottom to top is disclosed. The sub collector/separating layer and the pHEMT sub structure are combined to form a pHEMT, and the sub collector/separating layer and the HBT sub structure are combined to form an HBT. The carbon concentration in the sub collector/separating layer is within 5×1017 cm−3 and 1×1020 cm−3, and/or the oxygen concentration within 5×1018 cm−3 and 1×1020 cm−3. The lattice during the process of epitaxy growth is stabilized and it is possible to prevent the dopants, the elements, the vacancies or the defects from diffusing into the neighboring layers, thereby improving the problem of mobility degradation and resistance increase, and sustaining the stability of the manufacturing process.