Plasma Antenna Charging in CMOS Image Sensors

Sacchettini, Y.; Carrere, J.-P.; Goiffon, Vincent; Magnan, Pierre

doi:10.1109/irps.2019.8720518

Cited by 5 publications

(3 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…First, the voltage at the wafer surface is well known [4] to generate gate oxide damage by the antenna charging effect. We have demonstrated elsewhere [5] that such oxygen plasma can degrade a 5 nm MOS gate oxide by antenna voltage reaching about 9-10 V. Here, such an antenna effect is not probable, because the damage occurs during a dielectric etch and strip process: there is no conductive area exposed to the plasma. Moreover, the dark current damage does not depend on the transfer gate oxide area.…”

Section: Experimental Set-upmentioning

confidence: 94%

CMOS Image Sensors and Plasma Processes: How PMD Nitride Charging Acts on the Dark Current

Sacchettini

Carrere

Duru

et al. 2019

Sensors

View full text Add to dashboard Cite

Plasma processes are known to be prone to inducing damage by charging effects. For CMOS image sensors, this can lead to dark current degradation both in value and uniformity. An in-depth analysis, motivated by the different degrading behavior of two different plasma processes, has been performed in order to determine the degradation mechanisms associated with one plasma process. It is based on in situ plasma-induced charge characterization techniques for various dielectric stack structures (dielectric nature and stack configuration). A degradation mechanism is proposed, highlighting the role of ultraviolet (UV) light from the plasma in creating an electron hole which induces positive charges in the nitride layer at the wafer center, and negative ones at the edge. The trapped charges de-passivate the SiO2/Si interface by inducing a depleted interface above the photodiode, thus emphasizing the generation of dark current. A good correlation between the spatial distribution of the total charges and the value of dark current has been observed.

show abstract

Section: Experimental Set-upmentioning

confidence: 94%

CMOS Image Sensors and Plasma Processes: How PMD Nitride Charging Acts on the Dark Current

Sacchettini

Carrere

Duru

et al. 2019

Sensors

View full text Add to dashboard Cite

show abstract

“…Si recess) caused by plasma etching during mask processing deteriorates the device characteristics. [12][13][14] A V th shift of a MOS transistor is one of the issues caused by Si recess generation. This results in the yield loss of integrated circuit chips in semiconductor manufacturing.…”

Section: Introductionmentioning

confidence: 99%

Diffusion mechanism of fluorine in plasma processing of III–V semiconductor compounds

Kodama¹,

Zaizen²,

Minari³

et al. 2020

Jpn. J. Appl. Phys.

View full text Add to dashboard Cite

III–V semiconductors have attracted attention as high mobility channel materials in advanced metal oxide semiconductors. However, there is a possibility that their characteristics deteriorate owing to the damage caused by dry etching when processing the channel material. We focus on dry etching damage to InP and investigate the diffusion and injection of various elements. Secondary ion mass spectrometry (SIMS) shows that a fluorine atom can easily diffuse into the III–V semiconductor. Furthermore, we investigate the diffusion depths of other elements to determine the activation energies by using first-principles calculations. The SIMS results show the diffusion distance in the bulk InP is strongly correlated with the activation energy. Additionally, radicals containing F can easily diffuse into InP. Therefore, the number of radicals present in the gas phase of the plasma is important. An increase in the adsorption probability of the surface, owing to ion bombardment and knock-on phenomenon, is assumed.

show abstract

“…Unfortunately, despite the optical improvement, the BSI configuration exhibits several drawbacks from electrical and reliability points of view [1], [13], [14]. Some studies have been carried out to understand the reason for this degradation [15]- [17], but the debate is still going on and further research must be done. In recent studies, we demonstrated that, with respect to FSI, BSI-CIS gate oxides contain an additional distribution of donor-like traps [18], [19].…”

mentioning

confidence: 99%

On Border Traps in Back-Side-Illuminated CMOS Image Sensor Oxides

Vici

Russo²,

Lovisi³

et al. 2020

IEEE Trans. Electron Devices

View full text Add to dashboard Cite

CMOS image sensors (CISs) in back-sideilluminated configuration consist of photodiode arrays having metal lines and drive electronics beneath the active region with respect to the device/air interface so that the light reaches the photodiode active region directly. This enhances sensor quantum efficiency but reduces the electrical performance and reliability. The backside configuration is realized by flipping the wafer upside down, bonding it to a handling wafer, mechanically thinning it, and opening a through-silicon via with a long plasma etch. As a result, gate oxides in backside CISs show an increased density of donor-like border traps with respect to the conventional front-side-illuminated sensors. In this article, we try to add some information toward the comprehension of the origin and the electrical nature of those traps in backside gate oxides. To this aim, we performed negative bias temperature instability stress on p-channel MOSFETs during which the traps were filled by holes tunneling from the substrate and then studied the relaxation transients of the drain current after the stress was removed. The characteristic emission times of a few specific levels were obtained at different temperatures. This allowed us to extract values of the trap activation energies, which resulted coherent with hole-capturing E donor-like centers (trivalent silicon dangling bonds) commonly attributed to ionizing radiation. Index Terms-Backside illuminated (BSI) CMOS image sensors (CISs), gate oxide border traps, TDDS. I. INTRODUCTION A CMOS image sensor (CIS) is an array of light-sensitive pixels. Each pixel consists of a photo-diode (PD) and several control MOSFETs. In the front-side-illuminated (FSI) configuration [Fig. 1(a)], the light reaches the PD active region through the microlenses, the filters, the passivation layers, the metal lines, and the interdielectric layers [1], [2]. So, the Manuscript

show abstract

Plasma Antenna Charging in CMOS Image Sensors

Cited by 5 publications

References 10 publications

CMOS Image Sensors and Plasma Processes: How PMD Nitride Charging Acts on the Dark Current

CMOS Image Sensors and Plasma Processes: How PMD Nitride Charging Acts on the Dark Current

Diffusion mechanism of fluorine in plasma processing of III–V semiconductor compounds

On Border Traps in Back-Side-Illuminated CMOS Image Sensor Oxides

Contact Info

Product

Resources

About