相容於後段製程之雷射退火鐵電氧化鉿鋯數值模擬

Abstract

將具有鐵電效應之氧化鉿鋯 (HZO) 的鐵電記憶體 (FeRAM)，並採用BEOL (Back end of line) 後段製程與邏輯 IC 整合。為了得到其良好的鐵電記憶體殘餘極化量 (Remnant Polarization)、矯頑場 (Coercive field) 以及ID-VG 遲滯特性，透過退火使 HZO 薄膜結晶化是相當重要的步驟，由於採用 BEOL 後段製成，將無法以一般 RTA (Rapid Thermal Annealing) 進行退火，因為下層的邏輯 IC 無法承受 RTA 退火的高溫，所以選擇用雷射退火 (Laser Annealing) 的方式將 HZO 薄膜結晶化。由於實驗無法準確量測 HZO 薄膜在退火時的溫度分布，因此本實驗透過模擬 Nd: YAG 雷射退火使鐵電記憶體結晶化的過程，以及下層邏輯 IC 的在退火時的溫度狀況，並模擬不同結構與不同材料，探討熱在不同結構與不同材料中的傳遞與分布。

The ferroelectric memory (FeRAM) of hafnium zirconium oxide (HZO) with ferroelectric effect is integrated with logic IC using BEOL (Back end of line) process. In order to obtain good remnant polarization, coercive field and ID-VG hysteresis characteristics of ferroelectric memory, crystallization of HZO film by annealing is a very important step. Due to the BEOL process, annealing by general RTA (Rapid Thermal Annealing) cannot be performed, because the underlying logic IC cannot withstand the high temperature of RTA annealing, so laser annealing is chosen to crystallize the HZO film. Since the experiment cannot accurately measure the temperature distribution of the HZO film during annealing, this experiment simulates the crystallization process of the ferroelectric memory annealing by Nd: YAG laser, and the temperature condition of the underlying logic IC during annealing, discuss the heat transfer and distribution in different structures and different materials.