Vertical bipolar transistor and method for manufacturing same

Abstract

The invention discloses a vertical bipolar transistor and a method for manufacturing the same. The vertical bipolar transistor comprises a collector electrode area formed by a trap of a CMOS transistor, a base electrode area formed by using a high-voltage lightly doped drain electrode of a high-voltage transistor and an emitter electrode area formed on the surface of the base electrode area and by a source-drain of the CMOS transistor. The method fully uses the prior CMOS process, avoids the use of additional process steps and uses the base electrode formed by the high-voltage LDD of the high-voltage transistor; and because the junction depth of a PN junction formed by the high-voltage LDD and the trap is slightly deeper than that of the PN junction formed by the source-drain and the LDD, the base electrode of the formed vertical bipolar transistor has quite thin thickness, and consequentially the performance of the bipolar transistor is improved.

Description

technical field [0001] The present invention relates to a semiconductor device and a manufacturing method thereof, in particular to a vertical bipolar transistor and a manufacturing method thereof. Background technique [0002] Continuously shrinking the size of devices and increasing integration to obtain better performance are the goals pursued by integrated circuit technology and the driving force for development. Today, CMOS (Complementary Metal-Oxide-Silicon) technology has developed into a mainstream technology for integrated circuits. Generally speaking, CMOS is mainly used for digital applications, while for analog applications (such as radio signal processing), bipolar circuits are more suitable. So bipolar devices are still required in CMOS at some point. At present, in the manufacture of bipolar devices in the CMOS process, if no additional process steps are added, parasitic vertical bipolar transistors are generally used, that is, vertical transistors composed ...

AI Technical Summary

Problems solved by technology

But this method has the following two disadvantages. One, this method can only manufacture one type of bipolar transistor. If you use a P-type substrate, you can only manufacture a PNP type, and if you use an N-type substrate, you can only manufacture an NPN type. The reason is as follows: in the prior art, the well (well) is generally used as the base, while the collector (collector) uses the substrate of the silicon wafer, and the doping of the silicon wafer substrate is determined during the growth process of the silicon single crystal. , it is difficult to change without adding additional process steps in the process. Therefore, the type of transistors that can be manufactured by this method is limited by the doping of the silicon substrate. For the P-type substrate, only P+ / N well / P-substrate type bipolar transistors can be manufactured, because P well and P-substrate are the same doping type, N / P / N type bipolar transistors cannot be manufactured; 2. This method uses The well (well) is the base of the bipolar transistor, and the thickness of the base is the most important factor affecting the bipolar transistor. Generally speaking, the thinner the base is, the better the performance of the bipolar transistor is. Deep junction depth, resulting in a thick base of the bipolar transistor, which affects its performance

[0003] In summary, it can be seen that in the previous technology of manufacturing bipolar devices in the CMOS process, only one type of bipolar transistors can be manufactured and the use of wells as the base of bipolar transistors leads to the above-mentioned problems that the thickness of the base of bipolar transistors is very thick. , so it is necessary to propose improved technical means to solve this problem

Images