US 2003/0143786 A1 · Method of making an integrated photodetector

Abstract

A photodetector is integrated on a single semiconductor chip with bipolar transistors including a high speed poly-emitter vertical NPN transistor. The photodetector includes a silicon nitride layer serving as an anti-reflective film. The silicon nitride layer and oxide layers on opposite sides thereof insulate edges of a polysilicon emitter from the underlying transistor regions, minimizing the parasitic capacitance between the NPN transistor's emitter and achieving a high frequency response. The method of manufacture is compatible with existing BiCMOS process technology, the silicon nitride layer of the anti-reflective film being formed over the photodetector as well as regions of the chip that include the vertical NPN transistor and other circuit elements.

Claims10

Dependent claims

A method of manufacturing an integrated circuit device on a single semiconductor chip, comprising:

providing a substrate of a first conductivity type;
forming an epitaxial layer of a second conductivity type on the substrate;
and
forming transistors and a photodetector at laterally spaced locations on the chip, the transistors and photodetector being defined by active regions within the epitaxial layer and contacts corresponding to respective active regions, the contacts being formed above an upper surface of the epitaxial layer in contact with an active region;
wherein a silicon nitride layer is formed as an anti-reflective film in the structure of the photodetector, the silicon nitride layer extending laterally from the photodetector to regions of the chip that include the transistors and performing an insulating function within the structures of the transistors, wherein the contacts are formed after formation of the silicon nitride layer and extend through the silicon nitride layer.

2 more elements

A method of making an integrated photodetector device, comprising:

providing a body of semiconductor material;
forming N-type and P-type regions within the body including active transistor regions and regions defining a PN junction of a photodetector;
depositing a first oxide layer over the body overlying the transistor and photodetector active regions;
depositing a silicon nitride layer atop the first oxide layer;
depositing a second oxide layer atop the silicon nitride layer;
forming contact openings through the second oxide layer, silicon nitride layer and first oxide layer at selective locations above the body;
forming contacts in the openings to contact the various active regions of the transistors and photodetector;
depositing an interlevel dielectric layer;
planarizing the interlevel dielectric layer to provide a planarized top surface;
depositing a metal screen plate atop the interlevel dielectric layer;
depositing a passivation layer over the device;
and
selectively removing portions of the passivation layer, the metal screen plate, the interlevel dielectric layer, and the second oxide layer to expose the silicon nitride layer over the photodetector.

10 more elements

Dependencies are inferred from the claim text.

Method of making an integrated photodetector

Life of this patent

Method of making an integrated photodetector

Life of this patent

Abstract

Claims10