Reliability and failure analysis of Bipolar Junction Transistor (BJT)

Lim, Ching Yit (2008) Reliability and failure analysis of Bipolar Junction Transistor (BJT). Universiti Malaysia Sabah. (Unpublished)


Download (994kB) | Preview


This research is a failure analysis for bipolar junction transistor (BJT) to observe the changes of current gain, ß with the increase of input voltage on transistor in different frequency in an amplifier circuit We also observe the changes of current gain with increase of temperature effect on transistor. 2N2222A n-channel enhancement BIT transistor was used. This transistor in the amplifier circuit is to test on it when the function of transistor meets the failure. Multimeter was connected in the circuit to get the base current and collector current. These parameters are important as it use to calculate the current gain of the circuit. The values of the current are recorded from each increment of 0.1 V of input voltage starting from 1.0V until the transistor meets the failure point. The process is repeated for different frequency from 2 kHz to 20 kHz. The values of the current are also recorded for every 5 °C temperature increase starting from 25°C until 100°C . This process is repeated for different transistor. Graph of current gain versus input voltage and current gain versus temperature are plotted. From the graph, it showed that transistor operated in higher frequency will meet the failure point at lower voltage input with increasing input voltage. It also showed that the transistor function normally within the range of 100°C. Through the research, we found that the internal temperature is increasing while operating under high voltage and frequency as high electrical and thermal stresses at the semiconductor surface of transistor and cause the transistor to the failure. From the experiment, we conclude that the current gain in the amplifier circuit work. well and efficient at the range of input between 1.3V and 2.6V. Failure point (ß≈0) decreased in the input voltage range from 4.2V to 3.6V when frequency increased.

Item Type: Academic Exercise
Keyword: Bipolar Junction Transistor (BJT), voltage, transistor, amplifier circuit, temperature
Subjects: Q Science > QC Physics
Department: SCHOOL > School of Science and Technology
Depositing User: ADMIN ADMIN
Date Deposited: 02 Jun 2016 09:53
Last Modified: 30 Oct 2017 10:00

Actions (login required)

View Item View Item