Didier Née

EEPROM Diagnosis Based on Threshold Voltage Embedded Measurement

Knowing, that the threshold voltage of the EEPROM memory cells is a key parameter to determine the overall performance of the memory, a built in structure to extract this information is a very relevant choice to fast diagnose the failure in the memory. Thus, the objective of this paper is to present a built in self-diagnosis of EEPROM memory cells, based on threshold voltage extraction. In order to extract the threshold voltage, the modified circuit and the associated test sequence are presented. Based on the threshold voltage extraction, complementary information is proposed to improve the classical memory diagnosis methodology.

Test Structure for Process and Product Evaluation

The objective of this paper is to present a test structure introduced in the scribe lines designed to detect process drift and to characterize product performances, i.e. delay and VDDmin. A brief overview of the structure, designed in a ST-Microelectronics 130nm technology, is given. The main advantages of the structure are to be introduced in the scribe line and to have a complex architecture close to the product back-end configurations. A specific test flow is applied to the structure in order to extract relevant data (frequency, delay and bias). The monitoring efficiency of the structure is validated with measurement correlation performed on the structure data, parametric test data and full test chip data.

A New Embedded Measurement Structure for eDRAM Capacitor

The embedded DRAM (eDRAM) is more and more used in system-on-chip (SOC). It is challenging to integrate the DRAM capacitor process into a logic process to get satisfactory yields. The specific process of DRAM capacitor and the low capacitance value (/spl sim/30 fF) of this device induce problems of process monitoring and failure analysis. We propose a new test structure to measure the capacitance value of each DRAM cell capacitor in a DRAM array. This concept has been validated by simulation on a 0.18 /spl mu/m eDRAM technology.