The invention relates to a diode capable of alternately operating as a detector and emitter of light in the same frequency band. This diode comprises an active zone disposed between two localizing zones and respectively forming two hetero-junctions with these zones. The reverse biassing voltage is such that the active zone is the seat of the avalanche phenomenon.

Diode capable of alternately functioning as an emitter and detector of light of the same wavelength

A method of forming a planar semiconductor device, such as an array of APDs, includes the steps of doping a substantially planar block of n type semiconductor material with a p type dopant in accordance with a selected pattern to form a plurality of n type wells in the block surrounded by a foundation of p type semiconductor material. Each n type well is disposed so as to respectively adjoin a first surface of the block and such that a respective p-n junction is formed between the n type material in the well and the p type material foundation. The n type semiconductor material in each well has a substantially constant concentration of n type dopant throughout the n type material; the concentration of p type dopant in the foundation has a positive gradient extending from the p-n junction towards the second surface such that the peak surface electric field of the p-n junction in each well is less than the bulk electric field of the same p-n junction.

Method for fabrication of deep-diffused avalanche photodiode

A method of forming a planar photosensitive device, such as an array of APDs, includes the steps of doping a substantially planar block of n type semiconductor material with a p type dopant in accordance with a selected pattern to form a plurality of p type wells in the block surrounded by a foundation of n type semiconductor material. Each p type well corresponds to an APD pixel and is disposed so as to respectively adjoin a first surface of the block and such that a respective p-n junction is formed between the p type material in the well and the n type material foundation. Each APD pixel further comprises depletion layer profile modification means such that the peak surface electric field of the p-n junction in each well is substantially less than the bulk electric field of the same p-n junction. One type of depletion layer profile modification means is an peripheral doped region of p material disposed around each respective well; an alternative depletion layer profile modification means is a respective isolation moat around each well so as to separate p type material in the well from n type material in the foundation except along a parallel plane segment of the p-n junction.

Method for fabricating planar avalanche photodiode array

A planar photosensitive device, such as an array of APDs, includes a planar block of n type semiconductor material having a plurality of p type wells in the block surrounded by a foundation of n type semiconductor material. Each p type well corresponds to an APD pixel and is disposed so as to respectively adjoin a first surface of the block and such that a respective p-n junction is formed between the p type material in the well and the n type material foundation. Each APD pixel further comprises depletion layer profile modification means such that the peak surface electric field of the p-n junction in each well is substantially less than the bulk electric field of the same p-n junction. One type of depletion layer profile modification means is a peripheral doped region of p material disposed around each respective well; an alternative depletion layer profile modification means is a respective isolation moat around each well so as to separate p type material in the well from n type material in the foundation except along a parallel plane segment of the p-n junction.

Planar avalanche photodiode array with sidewall segment

An avalanche photodiode (APD) has a first semiconductor layer (110) that is doped to exhibit p type conductivity and a second semiconductor layer (120) that is doped to exhibit n type conductivity. The first and second semiconductor layers are disposed adjacent to one another to form a p-n junction (130). The first and second semiconductor layers further have a deep level lifetime-reducing dopant that has relatively large carrier cross sections distributed therethrough. Platinum is used as the lifetime reducing dopant. The platinum-doped semiconductor layers exhibit at least one recombination center located between about 100 mV and 450 mV from the center of the energy bandgap. The platinum-doped APD exhibits lower low level and high level lifetimes than a non-doped silicon APD and further does not exhibit an increased bulk leakage current.

Platinum doped silicon avalanche photodiode

1,215,557. Semi-conductor devices. NIPPON ELECTRIC CO. Ltd. 30 July, 1969 [30 July, 1968], No. 38294/69. Heading H1K. The dimensions of a P + PNN + photosensitive device are selected so that when reverse biased at its reverse breakdown voltage the depletion layers nearly fill the P and N type regions. As shown, Fig. 2, an avalanche-type photodiode comprises an N type epitaxial layer 3 doped with As grown on an N type Si substrate 4, and having a P type layer 2 and a P + type layer 1 formed by diffusion of Ga and B respectively. The P and N type regions have relatively low impurity concentrations so that a junction with a low impurity concentration gradient is obtained. The device has uniform avalanche properties over the junction area without reduction of the internal quantum efficiency or increase in the spreading resistance. Design equations are given. The semi-conductor material may also be Ge, GaAs, GaP, or InSb.

Nishida Katsuhiko

Papers

A semiconductor photosensitive device