Yun Y.,Image Development Group |
Kim M.,Image Development Group
ISOCC 2012 - 2012 International SoC Design Conference | Year: 2012
This paper shows a method of WDR (wide dynamic range) in camera. When we make a digital WDR, commonly we meet two problems. The first one is an increase of noise. And the other is a lot of control factors. In this paper we will show a WDR with low noise and small number of control factors. The circuit is very simple and needs no memory. So the chip size is nearly unchanged after implementation. When all area of image is dark, the weighting factors in this circuit are used like gain by changing control factors. But the noise is not increased like gain. This algorithm has no frame rate down even in preview mode. © 2012 IEEE.
Choi C.S.,Image Development Group |
Yeo S.C.,KAIST |
Kim D.,Image Development Group |
Kim J.,Image Development Group |
And 2 more authors.
Journal of Electronic Materials | Year: 2014
Backside illumination complementary metal oxide semiconductor image sensors (BSI CISs) represent an advanced technology that produces high-quality image sensors. However, BSI CISs are limited by high dark signals and noise signals on the backside. To address these problems, backside junctions are commonly used. High-dose backside junctions effectively reduce dark signals and noise signals. The depth of the implantation profile is a key factor in determining the junction depth. A laser thermal annealing process is conducted only near the surface to the activation, and thus broader doping profiles are limitations to be activation of dopants. Changing the dopant from B to BF2 can decrease the implant projected range. However, there are abnormal activation rates for BF2 in applications involving laser thermal annealing processes for shallow junctions. Although the need for BF2 is increasing, a mechanism for its slow activation and low activation rates has not yet been confirmed. Here, we identify the mechanism by which BF2 undergoes low activation after a melting threshold temperature and explain why this phenomenon occurs. In addition, we confirm a condition that provides high activation rates of BF2 and show the reduction of dark signals and noise signals at the high density BSI CISs. © 2014 The Minerals, Metals & Materials Society.