CN208835083U - A kind of novel photodiode - Google Patents

Abstract

The utility model discloses a kind of novel photodiodes, including p-type electrode, p-type semiconductor layer, intrinsic semiconductor layer, n-type semiconductor layer, SiO2 layers and n-type electrode, the p-type electrode, p-type semiconductor layer, intrinsic semiconductor layer, n-type semiconductor layer and SiO2 layers are cascading, there are the Cutting Road for being cut, the n-type electrodes to pass through SiO2 layers and be connected to n-type semiconductor layer for SiO2 layers of the surrounding.For SiO2 layers of the surrounding there are Cutting Road, the Cutting Road is no silicon dioxide region, and SiO2 layers is have silicon dioxide region, and the figure worked it out has an apparent colouring discrimination, and when cutting can differentiate well；In addition; since there are Cutting Roads; the Cutting Road is no silicon dioxide region; therefore SiO2 layers of structure is not interfered in cutting; the SiO2 layer around cutting region can be protected from arriving physical damage; it avoids and the case where electric leakage occurs because of SiO2 damage layer, protect the performance of photodiode significantly.

Description

A kind of novel photodiode

Technical field

The utility model relates to diode field, especially a kind of novel photodiode.

Background technique

Photodetector is a kind of device that optical signal is detected by photoelectric effect, and photodiode is exactly a kind of typical case Photodetector.Photodiode English is PhotoDiode, abbreviation PD, it is worked under backward voltage, without light According to when, reverse current is extremely faint, is dark current, general several Naans；When having illumination, in the state of backward voltage, reversely Electric current moment increases tens microamperes or more, referred to as photoelectric current (light current).The intensity of light is bigger, and reverse current is bigger, the change of light Change the curent change for causing photodiode, optical signal is just also converted into electric signal, becomes optoelectronic sensor.Its core Part is also that a PN junction is compared with general-purpose diode, structurally different, is shone for the ease of receiving incident light, PN junction Photosensitive area is done larger as far as possible, and electrode area is as small as possible, and the junction depth of PN junction is very shallow, general several microns.It is photosensitive Diode is widely used in light-controlled switching circuit, and optocoupler and road lamp switch are medium, and there are also infrared tube and oncontactings for present new application Point keyboard etc..

The most important parameter of PD chip: positive VF, backward voltage VBR, reversed dark current ID under no light condition and there is light Photoelectric current IL when backward voltage is met under state.The performance that chip will be got well is very big with layout design relationship.Layout design Any one change can all bring greater impact performance.Existing photodiode can all be covered with one on cutting region The thicker silicon dioxide passivation layer of layer, and its cutting uses emery wheel cuts substantially, can destroy silicon dioxide passivation layer in the process Structure, be easy to cause electric leakage, a degree of influence caused on the performance of photodiode.

Utility model content

To solve the above problems, can protect and cut the purpose of this utility model is to provide a kind of novel photodiode The SiO2 layer around region is cut from avoiding and the case where electric leakage occur because of SiO2 damage layer, protect significantly to physical damage The performance of photodiode.

The technical solution adopted by the utility model to solve the problem is as follows:

A kind of novel photodiode, it is characterised in that: including p-type electrode, p-type semiconductor layer, intrinsic semiconductor layer, n Type semiconductor layer, SiO2 layers and n-type electrode, the p-type electrode, p-type semiconductor layer, intrinsic semiconductor layer, n-type semiconductor layer and SiO2 layers are cascading, and there are the Cutting Road for being cut, the n-type electrodes to pass through for SiO2 layers of the surrounding SiO2 layers are connected to n-type semiconductor layer.

It further, further include isolation ring and p cut-off region, the isolation ring and p cut-off region, which are successively surround, is layered in the n The surrounding of type semiconductor layer, described SiO2 layers is covered on the same side of n-type semiconductor layer, isolation ring and p cut-off region, institute simultaneously The surface that SiO2 layers of edge is located at p cut-off region is stated, and there are described to cut between the edge of the p cut-off region It cuts.

Further, the isolation ring is single crystalline layer.

Further, it is provided with fairlead for described SiO2 layers, the n-type electrode passes through fairlead and is connected to n-type semiconductor Layer.

Further, the n-type electrode includes interconnecting part and the extension for external bonding wire, one end of the interconnecting part It is connected to n-type semiconductor layer across fairlead, the other end is connected to extension, and SiO2 layers of surface is arranged in the extension.

Further, SiO2 layers of marginal position is arranged in the fairlead.

Further, the external form of the extension is in the external form arrangement along SiO2 layers.

Further, the square-shaped setting of the extension.

Further, the p-type electrode, p-type semiconductor layer, intrinsic semiconductor layer, n-type semiconductor layer and SiO2 layers it is total Body thickness is 300nm.

The beneficial effects of the utility model are: a kind of novel photodiode that the utility model uses, including p-type electricity Pole, p-type semiconductor layer, intrinsic semiconductor layer, n-type semiconductor layer, SiO2 layers and n-type electrode, the p-type electrode, p-type semiconductor Layer, intrinsic semiconductor layer, n-type semiconductor layer and SiO2 layer are cascading, and there are for carrying out for SiO2 layers of the surrounding The Cutting Road of cutting, the n-type electrode pass through SiO2 layers and are connected to n-type semiconductor layer.SiO2 layers of surrounding in the utility model There are the Cutting Road for being cut, the Cutting Road is no silicon dioxide region, and SiO2 layers are to have silicon dioxide region, The figure worked it out has an apparent colouring discrimination, and when cutting can differentiate well；In addition, since there are Cutting Roads, it is described to cut It cuts as no silicon dioxide region, therefore does not interfere with SiO2 layers of structure in cutting, can protect around cutting region SiO2 layer from arrive physical damage, avoid and the case where electric leakage occur because of SiO2 damage layer, protect photosensitive two pole significantly The performance of pipe.

Detailed description of the invention

The utility model is described in further detail with example with reference to the accompanying drawing.

Fig. 1 is a kind of top view of the novel photodiode of the utility model when hiding SiO2 layers；

Fig. 2 is a kind of cross-sectional view of novel photodiode of the utility model.

Specific embodiment

- Fig. 2 referring to Fig.1, a kind of novel photodiode of the utility model, including p-type electrode 100, p-type semiconductor Layer 200, intrinsic semiconductor layer 300, n-type semiconductor layer 400, SiO2 layer 500 and n-type electrode 600, the p-type electrode 100, p-type Semiconductor layer 200, intrinsic semiconductor layer 300, n-type semiconductor layer 400 and SiO2 layer 500 are cascading, SiO2 layers described There are the Cutting Road 900 for being cut, the n-type electrodes 600 to be connected to N-shaped across SiO2 layer 500 and partly lead for 500 surrounding Body layer 400.

There are the Cutting Road 900 for being cut, the Cutting Roads 900 for the surrounding of SiO2 layer 500 in the utility model For no silicon dioxide region, and SiO2 layer 500 is to have silicon dioxide region, and the figure worked it out has apparent colouring discrimination, cuts It can be differentiated well when cutting；In addition, the Cutting Road 900 is no silicon dioxide region, therefore due to there are Cutting Road 900 The structure that SiO2 layer 500 is not interfered in cutting can protect the SiO2 layer 500 around cutting region from broken to physics It is bad, the case where leaking electricity because of the destruction of SiO2 layer 500 is avoided, electric leakage yield, cutting yield is promoted, protects significantly photosensitive The performance of diode.

It further, further include isolation ring 700 and p cut-off region 800, the isolation ring 700 and p cut-off region 800 successively ring Around the surrounding for being layered in the n-type semiconductor layer 400, the SiO2 layer 500 is covered on n-type semiconductor layer 400, isolation ring simultaneously The same side of 700 and p cut-off region 800, the edge of the SiO2 layer 500 are located at the surface of p cut-off region 800, and with institute State between the edge of p cut-off region 800 that there are the Cutting Roads 900.The P cut-off region 800 can end N-shaped and partly lead The electronics transverse shifting of body layer 400, while playing and completely cutting off extraneous ion and electric field etc. to the Horizonal Disturbing of n-type semiconductor layer 400, The stability for improving chip, reduces dark current.The utility model designs the isolation ring 700 and p cut-off region 800, guarantees Backward voltage, reduces dark current, improves the stability of chip.

Further, the isolation ring 700 is single crystalline layer.The isolation ring 700 is high resistant single crystalline layer, its width isolation P cut-off region 800 and n-type semiconductor layer 400, the P cut-off region 800 do not have electric field, and electronics will not generate offset, the isolation The barrier meeting of ring 700 is so that dark current is smaller, while the presence of isolation ring 700 can also improve backward voltage, promotes photosensitive two The performance of pole pipe.

Further, the SiO2 layer 500 is provided with fairlead 510, and the n-type electrode 600 is connected across fairlead 510 To n-type semiconductor layer 400.

Further, the n-type electrode 600 includes interconnecting part 610 and the extension 620 for external bonding wire, the company The one end in logical portion 610 passes through fairlead 510 and is connected to n-type semiconductor layer 400, and the other end is connected to extension 620, the extension The surface of SiO2 layer 500 is arranged in portion 620.The position of the fairlead 510 determines the scalability of electric current, while needing to do It is as small as possible, design its band of position not in the lower section in bonding wire region, but extend away, this is one to fairlead 510 Kind of protection, power is excessive when preventing bonding wire, and there is difference in height in the region in hole, may destroy fairlead 510 and its coupling part.

Further, the marginal position of SiO2 layer 500 is arranged in the fairlead 510.

Further, the external form of the extension 620 is in the external form arrangement along SiO2 layer 500.

Further, the square-shaped setting of the extension 620.The extension 620 using rectangular, right angle portions with every It coincide from ring 700, improves the reliability of bonding wire.Outside is connected from 620 routing of extension, since photodiode is to light Very sensitive, soldered ball when bonding wire can be light-blocking, and the edge for the chip that the position of electrode just needs to do, bonding wire would not be because of illumination band To influence.Usual electrode all uses circle, matches soldered ball, but right angle portions region in this way will expose, and light is easy after routing It is blocked, while very possible routing trains off a bit, directly beats in n-quadrant, destroys its structure, influences the reliability of chip. The utility model uses square-shaped electrode, is bonded substantially with 700 upper and lower position of isolation ring, and error when routing does not interfere with N-quadrant.

Further, the p-type electrode 100, p-type semiconductor layer 200, intrinsic semiconductor layer 300, n-type semiconductor layer 400 General thickness with SiO2 layer 500 is 300nm.

The above, the only preferred embodiment of the utility model, the utility model are not limited to above-mentioned implementation Mode, as long as its technical effect for reaching the utility model with identical means, all should belong to the protection scope of the utility model.

Claims (9)

1. a kind of novel photodiode, it is characterised in that: including p-type electrode (100), p-type semiconductor layer (200), intrinsic half Conductor layer (300), n-type semiconductor layer (400), SiO2 layers (500) and n-type electrode (600), the p-type electrode (100), p-type half Conductor layer (200), intrinsic semiconductor layer (300), n-type semiconductor layer (400) and SiO2 layers (500) are cascading, described There are the Cutting Road (900) for being cut, the n-type electrodes (600) to pass through SiO2 layers for the surrounding of SiO2 layers (500) (500) n-type semiconductor layer (400) are connected to.

2. a kind of novel photodiode according to claim 1, it is characterised in that: further include that isolation ring (700) and p are cut Only area (800), the isolation ring (700) and p cut-off region (800) successively surround and are layered in the four of the n-type semiconductor layer (400) Week, SiO2 layers described (500) are covered on the same of n-type semiconductor layer (400), isolation ring (700) and p cut-off region (800) simultaneously Side, the edge of SiO2 layers described (500) are located at the surface of p cut-off region (800), and four with the p cut-off region (800) There are the Cutting Road (900) between circumferential edges.

3. a kind of novel photodiode according to claim 2, it is characterised in that: the isolation ring (700) is monocrystalline Layer.

4. a kind of novel photodiode according to claim 1, it is characterised in that: SiO2 layers described (500) are provided with Fairlead (510), the n-type electrode (600) pass through fairlead (510) and are connected to n-type semiconductor layer (400).

5. a kind of novel photodiode according to claim 4, it is characterised in that: the n-type electrode (600) includes connecting One end of logical portion (610) and the extension (620) for external bonding wire, the interconnecting part (610) is connected across fairlead (510) To n-type semiconductor layer (400), the other end is connected to extension (620), and the extension (620) is arranged at SiO2 layers (500) Surface.

6. a kind of novel photodiode according to claim 5, it is characterised in that: fairlead (510) setting exists The marginal position of SiO2 layers (500).

7. a kind of novel photodiode according to claim 6, it is characterised in that: the external form of the extension (620) In the external form arrangement along SiO2 layers (500).

8. a kind of novel photodiode according to claim 7, it is characterised in that: the extension (620) is square Shape setting.

9. a kind of novel photodiode according to claim 1, it is characterised in that: the p-type electrode (100), p-type half Conductor layer (200), intrinsic semiconductor layer (300), the general thickness of n-type semiconductor layer (400) and SiO2 layers (500) are (300) nm。