Laser-induced hot carrier injection (hci) for accelerated aging of integrated circuits

#In the manufacture of integrated circuit (IC) devices, Hot Carrier Injection (HCI) damage is an important aging process to understand. Hot carrier injection (HCI) is a phenomenon in solid-state electronic devices where a charge carrier (e.g., electron or hole) gains kinetic energy with the term “hot” referring to the effective temperature used to model carrier density (e.g., with a Fermi-Dirac function). Consequences of HCI include increased transistor leakage current and permanent physical damage to the gate insulator and/or channel interface or drain material if the hot carrier disrupts atomic structure. When interface states are created, the threshold voltage is modified and subthreshold slope is degraded. This leads to lower on-state current and degrades the operating frequency of integrated circuit. Accordingly, HCI is one of the mechanisms that adversely affects the reliability of semiconductors of solid-state devices

#Internal electric field strength increases in aggressively scaled MOSFETs, which increases switching speed, but also presents a major reliability problem for the long term operation of these devices because the high fields induce more HCI during normal operation over the lifetime of the IC device. The accumulation of damage in device behavior attributable to hot carrier injection is called “hot carrier degradation.” The useful lifetime of an IC device is thus affected by the lifetime of the MOS transistor itself. To assure an IC device will not have its useful life impaired by HCI, HCI degradation must be well understood.

#Transistor damage associated with hot carrier injection occurs in various operating conditions of a transistor, but the primary mode of concern is during switching in a digital circuit. Most of the HCI damage is thought to occur when the transistor transitions from the OFF state, at which point there exists a large lateral field from source to drain, to the ON state when current flows. Initial charge carriers during the transition are accelerated by the peak electrical field and enter the drain with particularly high energies.

#The material described herein is illustrated by way of example and not by way of limitation in the accompanying figures. For simplicity and clarity of illustration, elements illustrated in the figures are not necessarily drawn to scale. For example, the dimensions of some elements may be exaggerated relative to other elements for clarity. Further, where considered appropriate, reference labels have been repeated among the figures to indicate corresponding or analogous elements. In the figures:

#FIG. 1 is a schematic of a laser-based system suitable for accelerating damage through hot carrier injection, in accordance with some microprobe embodiments;

#FIG. 2 is a schematic of a laser-based system suitable for accelerating damage through hot carrier injection, in accordance with some alternative embodiments;

#Embodiments are described with reference to the enclosed figures. While specific configurations and arrangements are depicted and discussed in detail, this is done for illustrative purposes only. Persons skilled in the relevant art will recognize that other configurations and arrangements are possible without departing from the spirit and scope of the description. It will be apparent to those skilled in the relevant art that techniques and/or arrangements described herein may be employed in a variety of other systems and applications other than what is described in detail herein.

#Reference is made in the following detailed description to the accompanying drawings, which form a part hereof and illustrate exemplary embodiments. Further, it is to be understood that other embodiments may be utilized and structural and/or logical changes may be made without departing from the scope of claimed subject matter. It should also be noted that directions and references, for example, up, down, top, bottom, and so on, may be used merely to facilitate the description of features in the drawings. Therefore, the following detailed description is not to be taken in a limiting sense and the scope of claimed subject matter is defined solely by the appended claims and their equivalents.

#In the following description, numerous details are set forth. However, it will be apparent to one skilled in the art, that embodiments may be practiced without these specific details. In some instances, well-known methods and devices are shown in block diagram form, rather than in detail, to avoid obscuring the embodiments. Reference throughout this specification to “an embodiment” or “one embodiment” or “some embodiments” means that a particular feature, structure, function, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of the phrase “in an embodiment” or “in one embodiment” or “some embodiments” in various places throughout this specification are not necessarily referring to the same embodiment. Furthermore, particular features, structures, functions, or characteristics may be combined in any suitable manner in one or more embodiments. For example, a first embodiment may be combined with a second embodiment anywhere the particular features, structures, functions, or characteristics associated with the two embodiments are not mutually exclusive.