Since the PAMELA results on the "anomalously" high positron fraction and the lack of antiproton excess in our Galaxy, there has been a tremendous number of studies advocating new types of dark matter, with larger couplings to electrons than to quarks. This raises the question of the production of dark matter particles (and heavy associated coloured states) at LHC. Here, we explore a very simple benchmark dark matter model and show that, in spite of the agreement between the PAMELA antiproton measurements and the expected astrophysical secondary background, there is room for large couplings of a WIMP candidate to heavy quarks. Contrary to what could have been naively anticipated, the PAMELAp/p measurements do not challenge dark matter model building, as far as the quark sector is concerned. A quarkophillic species is therefore not forbidden. Owing to these large couplings, one would expect that a new production channel opens up at the LHC, through quark-quark and quark-gluon interactions. Alas, when the PDF of the quark is taken into account, prospects for a copious production fade away.

During the device fabrication, thin dielectric layers experience a wide range of photoresist ͑PR͒ strip processes after various implantations carried out with the thin dielectric layers exposed. Degradation of the thin dielectric layers by the PR strip process using O 2 plasma is well known to cause yield reduction and reliability deterioration. This paper investigates a PR strip method using ozone ͑O 3 ͒ followed by sulfuric-peroxide mixture ͑SPM͒ solution cleaning and finds it significantly effective in PR strip performance even at the damaged PR by high-dose and high-energy implantations. The method dramatically reduces gate leakage current, resulting in significant improvement in gate oxide integrity. The PR strip technology is significantly effective for the reduction of plasma damage-induced dark current and white pixel defects of a 1.3 mega-pixel complementary metal oxide semiconductor image sensor fabricated with 0.18 m technology node.Plasma damage on large scale integration is receiving a lot of attention as the technology strongly requires even more stringent control than ever for damage free process. 1 The plasma damage is well known to degrade the thin dielectric layers by generating electron hole pairs ͑EHP͒ in oxide and trap charges at Si-SiO 2 interface, resulting in gate oxide leakage current, threshold voltage ͑V th ͒ shift, and deterioration of gate oxide reliability. 2 Many studies have focused on the shift of electrical characteristics and device reliability caused by the plasma charging damage during the exposure of the thin dielectric layers to plasma. [1][2][3][4] The demand for low-plasma-induced leakage imposes a challenge on the complementary metal oxide semiconductor ͑CMOS͒ image sensor technology also. The plasma damage could induce the trap charges onto the Si-SiO 2 interface on photodiode ͑PD͒ area of CMOS image sensor pixel and cause an extreme leakage current. The leakage current in the PD area is well known to be one of the most critical sources of the dark current and white pixel defects. [5][6][7][8] The dark current and white pixel defects are important means for characterizing the performance of an image sensor and correlated with the reduction of the amount of white pixel defects in dark. 6 Recently, many works have been reported to reduce the plasma damage induced dark current in CMOS image sensor. 9 The O 2 plasma has been widely used for the photoresist ͑PR͒ strip process after the implantations implemented with the thin dielectric layers exposed, providing a serious source of plasma damage. This is why many companies have tried to develop PR strip process without using plasma, such as ozone alone, ozone injected water, ozone injected SPM, and SPM alone. However, the PR strip using SPM alone or ozone injected SPM showed an extreme PR residue even for the low dose implantations, because the chemical solution cleaning alone cannot break the PR surface hardened by ion bombardment during the implantations. This is why the SPM solution cleaning has been used only for the remov...

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