Abstract 2021

The diversified electronic market is in great need of configurable metal oxide metals (MOM) Capacitor structure . Based on the MOM Analysis and research of different capacitance sources in capacitors , And how the lithography process affects the final shape of the capacitor , We propose a highly configurable and scalable spiral based capacitor . Several forms of spiral capacitors have been generated and photolithography simulations have been carried out to obtain accurate capacitance values . And single layer interdigital MOM Compared with capacitors , The proposed spiral based capacitor has been configured to achieve ratio MOM Capacitor high 1.23 Times the capacitance density or the smallest change in all structures .

research

Capacitors play an important role in electronic applications [1]-[22]. With CMOS The continuous progress of Technology , The electronic market is further diversified and specialized . The capacitor of standard OEM is no longer “ One size fits all ”, Configurable and expandable capacitor structure is needed to meet the new market demand .
Usually , The foundry offers two types of capacitors , Metal - insulator - Metal (MIM) And metal - oxide - Metal (MOM) Capacitor .MIM Capacitors provide a high quality factor (Q Factor ) And low series resistance (ESR) characteristic , But it requires an additional insulating dielectric layer , This increases the manufacturing cost and manufacturing cycle [23]. Pictured 1 Sum graph 2 Shown ,MOM The capacitor is composed of copper metal interconnection layer , Its capacitance is estimated as area ( Due to the overlapping area ) 、 edge ( Coupling between conductors in different planes ) 、 And the landscape ( Coupling between non overlapping conductors in the same plane ) Parasitic capacitance . With the reduction of geometric distance between metal layers in advanced technology , This leads to capacitance density [1],[2],[23] An increase in . therefore ,MOM Capacitors have become MIM A better alternative to capacitors .
In order to achieve MOM The capacitor is lower ESR And higher Q factor , Fractal capacitors have been developed and used in microwave circuits [3]、[4]、 The antenna [5]、[6]、 transducer [7]、 transformer [8] , [9], Capacitor [10], [11], [22], coupler [12] 、 Transmission line [13] 、 filter [14] 、MEMS [15] 、 A / D converter [16] etc. . It uses the well-known space fill curve technique , By increasing the length of the periphery of the capacitor ( Number of corners ) To increase the capacitance density [22]. However , As the number of corners increases , Such as corner rounding ( short ) 、 The bridge ( short ) 、 extrusion / Necking ( open ) And line end pull back ( open ) Such lithography distortion will reduce the output of fractal capacitors ( chart 3). Parasitic extraction on physical layout polygons is no longer guaranteed (PEX) To estimate the capacitance .

In this paper , A highly configurable and scalable spiral based capacitor is proposed . The proposed structure is based on MOM From the analysis and research of different capacitance sources in the capacitor , And understand how the lithography process affects the final shape of the capacitor . In order to verify the performance of the proposed structure , Several forms of spiral capacitors have been generated and photolithography simulations have been carried out to obtain accurate capacitance values . And single layer interdigital MOM Compared with capacitors , The proposed spiral based capacitor realizes 1.23 Times the capacitance density , And the smallest change is achieved in all structures .

It just puts forward a structure .

Data sets

Experimental index

The specific methods